Merge pull request #4187 from LemonBoy/builtin-rearrange

Some needed work on builtins

7 files changed, 743 insertions, 1402 deletions

diff --git a/lib/std/os/linux/arm-eabi.zig b/lib/std/os/linux/arm-eabi.zig
index 2e55abd688..0fbbbc4085 100644
--- a/lib/std/os/linux/arm-eabi.zig
+++ b/lib/std/os/linux/arm-eabi.zig
@@ -88,15 +88,6 @@ pub fn syscall6(
 /// This matches the libc clone function.
 pub extern fn clone(func: extern fn (arg: usize) u8, stack: usize, flags: u32, arg: usize, ptid: *i32, tls: usize, ctid: *i32) usize;
 
-// LLVM calls this when the read-tp-hard feature is set to false. Currently, there is no way to pass
-// that to llvm via zig, see https://github.com/ziglang/zig/issues/2883.
-// LLVM expects libc to provide this function as __aeabi_read_tp, so it is exported if needed from special/c.zig.
-pub fn getThreadPointer() callconv(.C) usize {
-    return asm volatile ("mrc p15, 0, %[ret], c13, c0, 3"
-        : [ret] "=r" (-> usize)
-    );
-}
-
 pub fn restore() callconv(.Naked) void {
     return asm volatile ("svc #0"
         :
diff --git a/lib/std/special/c.zig b/lib/std/special/c.zig
index 9ff794d5b5..0a911ba52b 100644
--- a/lib/std/special/c.zig
+++ b/lib/std/special/c.zig
@@ -32,8 +32,6 @@ comptime {
         @export(strlen, .{ .name = "strlen", .linkage = .Strong });
     } else if (is_msvc) {
         @export(_fltused, .{ .name = "_fltused", .linkage = .Strong });
-    } else if (builtin.arch == builtin.Arch.arm and builtin.os == .linux) {
-        @export(std.os.linux.getThreadPointer, .{ .name = "__aeabi_read_tp", .linkage = .Strong });
     }
 }
 
diff --git a/lib/std/special/compiler_rt.zig b/lib/std/special/compiler_rt.zig
index 13caaacf01..2128883545 100644
--- a/lib/std/special/compiler_rt.zig
+++ b/lib/std/special/compiler_rt.zig
@@ -127,59 +127,57 @@ comptime {
     @export(@import("compiler_rt/fixtfsi.zig").__fixtfsi, .{ .name = "__fixtfsi", .linkage = linkage });
     @export(@import("compiler_rt/fixtfti.zig").__fixtfti, .{ .name = "__fixtfti", .linkage = linkage });
 
-    @export(@import("compiler_rt/udivmoddi4.zig").__udivmoddi4, .{ .name = "__udivmoddi4", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__udivmoddi4, .{ .name = "__udivmoddi4", .linkage = linkage });
     @export(@import("compiler_rt/popcountdi2.zig").__popcountdi2, .{ .name = "__popcountdi2", .linkage = linkage });
 
     @export(@import("compiler_rt/muldi3.zig").__muldi3, .{ .name = "__muldi3", .linkage = linkage });
-    @export(__divmoddi4, .{ .name = "__divmoddi4", .linkage = linkage });
-    @export(__divsi3, .{ .name = "__divsi3", .linkage = linkage });
-    @export(__divdi3, .{ .name = "__divdi3", .linkage = linkage });
-    @export(__udivsi3, .{ .name = "__udivsi3", .linkage = linkage });
-    @export(__udivdi3, .{ .name = "__udivdi3", .linkage = linkage });
-    @export(__modsi3, .{ .name = "__modsi3", .linkage = linkage });
-    @export(__moddi3, .{ .name = "__moddi3", .linkage = linkage });
-    @export(__umodsi3, .{ .name = "__umodsi3", .linkage = linkage });
-    @export(__umoddi3, .{ .name = "__umoddi3", .linkage = linkage });
-    @export(__divmodsi4, .{ .name = "__divmodsi4", .linkage = linkage });
-    @export(__udivmodsi4, .{ .name = "__udivmodsi4", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__divmoddi4, .{ .name = "__divmoddi4", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__divsi3, .{ .name = "__divsi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__divdi3, .{ .name = "__divdi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__udivsi3, .{ .name = "__udivsi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__udivdi3, .{ .name = "__udivdi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__modsi3, .{ .name = "__modsi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__moddi3, .{ .name = "__moddi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__umodsi3, .{ .name = "__umodsi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__umoddi3, .{ .name = "__umoddi3", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__divmodsi4, .{ .name = "__divmodsi4", .linkage = linkage });
+    @export(@import("compiler_rt/int.zig").__udivmodsi4, .{ .name = "__udivmodsi4", .linkage = linkage });
 
     @export(@import("compiler_rt/negXf2.zig").__negsf2, .{ .name = "__negsf2", .linkage = linkage });
     @export(@import("compiler_rt/negXf2.zig").__negdf2, .{ .name = "__negdf2", .linkage = linkage });
 
     if (is_arm_arch and !is_arm_64 and !is_test) {
-        @export(__aeabi_unwind_cpp_pr0, .{ .name = "__aeabi_unwind_cpp_pr0", .linkage = strong_linkage });
-        @export(__aeabi_unwind_cpp_pr1, .{ .name = "__aeabi_unwind_cpp_pr1", .linkage = linkage });
-        @export(__aeabi_unwind_cpp_pr2, .{ .name = "__aeabi_unwind_cpp_pr2", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_unwind_cpp_pr0, .{ .name = "__aeabi_unwind_cpp_pr0", .linkage = strong_linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_unwind_cpp_pr1, .{ .name = "__aeabi_unwind_cpp_pr1", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_unwind_cpp_pr2, .{ .name = "__aeabi_unwind_cpp_pr2", .linkage = linkage });
 
         @export(@import("compiler_rt/muldi3.zig").__muldi3, .{ .name = "__aeabi_lmul", .linkage = linkage });
 
-        @export(__aeabi_ldivmod, .{ .name = "__aeabi_ldivmod", .linkage = linkage });
-        @export(__aeabi_uldivmod, .{ .name = "__aeabi_uldivmod", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_ldivmod, .{ .name = "__aeabi_ldivmod", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_uldivmod, .{ .name = "__aeabi_uldivmod", .linkage = linkage });
 
-        @export(__divsi3, .{ .name = "__aeabi_idiv", .linkage = linkage });
-        @export(__aeabi_idivmod, .{ .name = "__aeabi_idivmod", .linkage = linkage });
-        @export(__udivsi3, .{ .name = "__aeabi_uidiv", .linkage = linkage });
-        @export(__aeabi_uidivmod, .{ .name = "__aeabi_uidivmod", .linkage = linkage });
+        @export(@import("compiler_rt/int.zig").__divsi3, .{ .name = "__aeabi_idiv", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_idivmod, .{ .name = "__aeabi_idivmod", .linkage = linkage });
+        @export(@import("compiler_rt/int.zig").__udivsi3, .{ .name = "__aeabi_uidiv", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_uidivmod, .{ .name = "__aeabi_uidivmod", .linkage = linkage });
 
-        @export(__aeabi_memcpy, .{ .name = "__aeabi_memcpy", .linkage = linkage });
-        @export(__aeabi_memcpy, .{ .name = "__aeabi_memcpy4", .linkage = linkage });
-        @export(__aeabi_memcpy, .{ .name = "__aeabi_memcpy8", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memcpy, .{ .name = "__aeabi_memcpy", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memcpy, .{ .name = "__aeabi_memcpy4", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memcpy, .{ .name = "__aeabi_memcpy8", .linkage = linkage });
 
-        @export(__aeabi_memmove, .{ .name = "__aeabi_memmove", .linkage = linkage });
-        @export(__aeabi_memmove, .{ .name = "__aeabi_memmove4", .linkage = linkage });
-        @export(__aeabi_memmove, .{ .name = "__aeabi_memmove8", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memmove, .{ .name = "__aeabi_memmove", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memmove, .{ .name = "__aeabi_memmove4", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memmove, .{ .name = "__aeabi_memmove8", .linkage = linkage });
 
-        @export(__aeabi_memset, .{ .name = "__aeabi_memset", .linkage = linkage });
-        @export(__aeabi_memset, .{ .name = "__aeabi_memset4", .linkage = linkage });
-        @export(__aeabi_memset, .{ .name = "__aeabi_memset8", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memset, .{ .name = "__aeabi_memset", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memset, .{ .name = "__aeabi_memset4", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memset, .{ .name = "__aeabi_memset8", .linkage = linkage });
 
-        @export(__aeabi_memclr, .{ .name = "__aeabi_memclr", .linkage = linkage });
-        @export(__aeabi_memclr, .{ .name = "__aeabi_memclr4", .linkage = linkage });
-        @export(__aeabi_memclr, .{ .name = "__aeabi_memclr8", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memclr, .{ .name = "__aeabi_memclr", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memclr, .{ .name = "__aeabi_memclr4", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_memclr, .{ .name = "__aeabi_memclr8", .linkage = linkage });
 
-        @export(__aeabi_memcmp, .{ .name = "__aeabi_memcmp", .linkage = linkage });
-        @export(__aeabi_memcmp, .{ .name = "__aeabi_memcmp4", .linkage = linkage });
-        @export(__aeabi_memcmp, .{ .name = "__aeabi_memcmp8", .linkage = linkage });
+        @export(@import("compiler_rt/arm.zig").__aeabi_read_tp, .{ .name = "__aeabi_read_tp", .linkage = linkage });
 
         @export(@import("compiler_rt/extendXfYf2.zig").__aeabi_f2d, .{ .name = "__aeabi_f2d", .linkage = linkage });
         @export(@import("compiler_rt/floatsiXf.zig").__aeabi_i2d, .{ .name = "__aeabi_i2d", .linkage = linkage });
@@ -301,8 +299,6 @@ const std = @import("std");
 const assert = std.debug.assert;
 const testing = std.testing;
 
-const __udivmoddi4 = @import("compiler_rt/udivmoddi4.zig").__udivmoddi4;
-
 // Avoid dragging in the runtime safety mechanisms into this .o file,
 // unless we're trying to test this file.
 pub fn panic(msg: []const u8, error_return_trace: ?*builtin.StackTrace) noreturn {
@@ -325,108 +321,6 @@ extern var __stack_chk_guard: usize = blk: {
     break :blk @bitCast(usize, buf);
 };
 
-fn __aeabi_unwind_cpp_pr0() callconv(.C) void {
-    unreachable;
-}
-fn __aeabi_unwind_cpp_pr1() callconv(.C) void {
-    unreachable;
-}
-fn __aeabi_unwind_cpp_pr2() callconv(.C) void {
-    unreachable;
-}
-
-fn __divmoddi4(a: i64, b: i64, rem: *i64) callconv(.C) i64 {
-    @setRuntimeSafety(is_test);
-
-    const d = __divdi3(a, b);
-    rem.* = a -% (d *% b);
-    return d;
-}
-
-fn __divdi3(a: i64, b: i64) callconv(.C) i64 {
-    @setRuntimeSafety(is_test);
-
-    // Set aside the sign of the quotient.
-    const sign = @bitCast(u64, (a ^ b) >> 63);
-    // Take absolute value of a and b via abs(x) = (x^(x >> 63)) - (x >> 63).
-    const abs_a = (a ^ (a >> 63)) -% (a >> 63);
-    const abs_b = (b ^ (b >> 63)) -% (b >> 63);
-    // Unsigned division
-    const res = __udivmoddi4(@bitCast(u64, abs_a), @bitCast(u64, abs_b), null);
-    // Apply sign of quotient to result and return.
-    return @bitCast(i64, (res ^ sign) -% sign);
-}
-
-fn __moddi3(a: i64, b: i64) callconv(.C) i64 {
-    @setRuntimeSafety(is_test);
-
-    // Take absolute value of a and b via abs(x) = (x^(x >> 63)) - (x >> 63).
-    const abs_a = (a ^ (a >> 63)) -% (a >> 63);
-    const abs_b = (b ^ (b >> 63)) -% (b >> 63);
-    // Unsigned division
-    var r: u64 = undefined;
-    _ = __udivmoddi4(@bitCast(u64, abs_a), @bitCast(u64, abs_b), &r);
-    // Apply the sign of the dividend and return.
-    return (@bitCast(i64, r) ^ (a >> 63)) -% (a >> 63);
-}
-
-fn __udivdi3(a: u64, b: u64) callconv(.C) u64 {
-    @setRuntimeSafety(is_test);
-    return __udivmoddi4(a, b, null);
-}
-
-fn __umoddi3(a: u64, b: u64) callconv(.C) u64 {
-    @setRuntimeSafety(is_test);
-
-    var r: u64 = undefined;
-    _ = __udivmoddi4(a, b, &r);
-    return r;
-}
-
-fn __aeabi_uidivmod(n: u32, d: u32) callconv(.C) extern struct {
-    q: u32,
-    r: u32,
-} {
-    @setRuntimeSafety(is_test);
-
-    var result: @TypeOf(__aeabi_uidivmod).ReturnType = undefined;
-    result.q = __udivmodsi4(n, d, &result.r);
-    return result;
-}
-
-fn __aeabi_uldivmod(n: u64, d: u64) callconv(.C) extern struct {
-    q: u64,
-    r: u64,
-} {
-    @setRuntimeSafety(is_test);
-
-    var result: @TypeOf(__aeabi_uldivmod).ReturnType = undefined;
-    result.q = __udivmoddi4(n, d, &result.r);
-    return result;
-}
-
-fn __aeabi_idivmod(n: i32, d: i32) callconv(.C) extern struct {
-    q: i32,
-    r: i32,
-} {
-    @setRuntimeSafety(is_test);
-
-    var result: @TypeOf(__aeabi_idivmod).ReturnType = undefined;
-    result.q = __divmodsi4(n, d, &result.r);
-    return result;
-}
-
-fn __aeabi_ldivmod(n: i64, d: i64) callconv(.C) extern struct {
-    q: i64,
-    r: i64,
-} {
-    @setRuntimeSafety(is_test);
-
-    var result: @TypeOf(__aeabi_ldivmod).ReturnType = undefined;
-    result.q = __divmoddi4(n, d, &result.r);
-    return result;
-}
-
 const is_arm_64 = switch (builtin.arch) {
     builtin.Arch.aarch64,
     builtin.Arch.aarch64_be,
@@ -446,1242 +340,3 @@ const is_arm_arch = switch (builtin.arch) {
 };
 
 const is_arm_32 = is_arm_arch and !is_arm_64;
-
-const use_thumb_1 = usesThumb1(builtin.arch);
-
-fn usesThumb1(arch: builtin.Arch) bool {
-    return switch (arch) {
-        .arm => |sub_arch| switch (sub_arch) {
-            .v6m => true,
-            else => false,
-        },
-        .armeb => |sub_arch| switch (sub_arch) {
-            .v6m => true,
-            else => false,
-        },
-        .thumb => |sub_arch| switch (sub_arch) {
-            .v5,
-            .v5te,
-            .v4t,
-            .v6,
-            .v6m,
-            .v6k,
-            => true,
-            else => false,
-        },
-        .thumbeb => |sub_arch| switch (sub_arch) {
-            .v5,
-            .v5te,
-            .v4t,
-            .v6,
-            .v6m,
-            .v6k,
-            => true,
-            else => false,
-        },
-        else => false,
-    };
-}
-
-test "usesThumb1" {
-    testing.expect(usesThumb1(builtin.Arch{ .arm = .v6m }));
-    testing.expect(!usesThumb1(builtin.Arch{ .arm = .v5 }));
-    //etc.
-
-    testing.expect(usesThumb1(builtin.Arch{ .armeb = .v6m }));
-    testing.expect(!usesThumb1(builtin.Arch{ .armeb = .v5 }));
-    //etc.
-
-    testing.expect(usesThumb1(builtin.Arch{ .thumb = .v5 }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumb = .v5te }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumb = .v4t }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumb = .v6 }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumb = .v6k }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumb = .v6m }));
-    testing.expect(!usesThumb1(builtin.Arch{ .thumb = .v6t2 }));
-    //etc.
-
-    testing.expect(usesThumb1(builtin.Arch{ .thumbeb = .v5 }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumbeb = .v5te }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumbeb = .v4t }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumbeb = .v6 }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumbeb = .v6k }));
-    testing.expect(usesThumb1(builtin.Arch{ .thumbeb = .v6m }));
-    testing.expect(!usesThumb1(builtin.Arch{ .thumbeb = .v6t2 }));
-    //etc.
-
-    testing.expect(!usesThumb1(builtin.Arch{ .aarch64 = .v8 }));
-    testing.expect(!usesThumb1(builtin.Arch{ .aarch64_be = .v8 }));
-    testing.expect(!usesThumb1(builtin.Arch.x86_64));
-    testing.expect(!usesThumb1(builtin.Arch.riscv32));
-    //etc.
-}
-
-const use_thumb_1_pre_armv6 = usesThumb1PreArmv6(builtin.arch);
-
-fn usesThumb1PreArmv6(arch: builtin.Arch) bool {
-    return switch (arch) {
-        .thumb => |sub_arch| switch (sub_arch) {
-            .v5, .v5te, .v4t => true,
-            else => false,
-        },
-        .thumbeb => |sub_arch| switch (sub_arch) {
-            .v5, .v5te, .v4t => true,
-            else => false,
-        },
-        else => false,
-    };
-}
-
-fn __aeabi_memcpy() callconv(.Naked) noreturn {
-    @setRuntimeSafety(false);
-    if (use_thumb_1) {
-        asm volatile (
-            \\ push    {r7, lr}
-            \\ bl      memcpy
-            \\ pop     {r7, pc}
-        );
-    } else {
-        asm volatile (
-            \\ b       memcpy
-        );
-    }
-    unreachable;
-}
-
-fn __aeabi_memmove() callconv(.Naked) noreturn {
-    @setRuntimeSafety(false);
-    if (use_thumb_1) {
-        asm volatile (
-            \\ push    {r7, lr}
-            \\ bl      memmove
-            \\ pop     {r7, pc}
-        );
-    } else {
-        asm volatile (
-            \\ b       memmove
-        );
-    }
-    unreachable;
-}
-
-fn __aeabi_memset() callconv(.Naked) noreturn {
-    @setRuntimeSafety(false);
-    if (use_thumb_1_pre_armv6) {
-        asm volatile (
-            \\ eors    r1, r2
-            \\ eors    r2, r1
-            \\ eors    r1, r2
-            \\ push    {r7, lr}
-            \\ b       memset
-            \\ pop     {r7, pc}
-        );
-    } else if (use_thumb_1) {
-        asm volatile (
-            \\ mov     r3, r1
-            \\ mov     r1, r2
-            \\ mov     r2, r3
-            \\ push    {r7, lr}
-            \\ b       memset
-            \\ pop     {r7, pc}
-        );
-    } else {
-        asm volatile (
-            \\ mov     r3, r1
-            \\ mov     r1, r2
-            \\ mov     r2, r3
-            \\ b       memset
-        );
-    }
-    unreachable;
-}
-
-fn __aeabi_memclr() callconv(.Naked) noreturn {
-    @setRuntimeSafety(false);
-    if (use_thumb_1_pre_armv6) {
-        asm volatile (
-            \\ adds    r2, r1, #0
-            \\ movs    r1, #0
-            \\ push    {r7, lr}
-            \\ bl      memset
-            \\ pop     {r7, pc}
-        );
-    } else if (use_thumb_1) {
-        asm volatile (
-            \\ mov     r2, r1
-            \\ movs    r1, #0
-            \\ push    {r7, lr}
-            \\ bl      memset
-            \\ pop     {r7, pc}
-        );
-    } else {
-        asm volatile (
-            \\ mov     r2, r1
-            \\ movs    r1, #0
-            \\ b       memset
-        );
-    }
-    unreachable;
-}
-
-fn __aeabi_memcmp() callconv(.Naked) noreturn {
-    @setRuntimeSafety(false);
-    if (use_thumb_1) {
-        asm volatile (
-            \\ push    {r7, lr}
-            \\ bl      memcmp
-            \\ pop     {r7, pc}
-        );
-    } else {
-        asm volatile (
-            \\ b       memcmp
-        );
-    }
-    unreachable;
-}
-
-fn __divmodsi4(a: i32, b: i32, rem: *i32) callconv(.C) i32 {
-    @setRuntimeSafety(is_test);
-
-    const d = __divsi3(a, b);
-    rem.* = a -% (d * b);
-    return d;
-}
-
-fn __udivmodsi4(a: u32, b: u32, rem: *u32) callconv(.C) u32 {
-    @setRuntimeSafety(is_test);
-
-    const d = __udivsi3(a, b);
-    rem.* = @bitCast(u32, @bitCast(i32, a) -% (@bitCast(i32, d) * @bitCast(i32, b)));
-    return d;
-}
-
-fn __divsi3(n: i32, d: i32) callconv(.C) i32 {
-    @setRuntimeSafety(is_test);
-
-    // Set aside the sign of the quotient.
-    const sign = @bitCast(u32, (n ^ d) >> 31);
-    // Take absolute value of a and b via abs(x) = (x^(x >> 31)) - (x >> 31).
-    const abs_n = (n ^ (n >> 31)) -% (n >> 31);
-    const abs_d = (d ^ (d >> 31)) -% (d >> 31);
-    // abs(a) / abs(b)
-    const res = @bitCast(u32, abs_n) / @bitCast(u32, abs_d);
-    // Apply sign of quotient to result and return.
-    return @bitCast(i32, (res ^ sign) -% sign);
-}
-
-fn __udivsi3(n: u32, d: u32) callconv(.C) u32 {
-    @setRuntimeSafety(is_test);
-
-    const n_uword_bits: c_uint = u32.bit_count;
-    // special cases
-    if (d == 0) return 0; // ?!
-    if (n == 0) return 0;
-    var sr = @bitCast(c_uint, @as(c_int, @clz(u32, d)) - @as(c_int, @clz(u32, n)));
-    // 0 <= sr <= n_uword_bits - 1 or sr large
-    if (sr > n_uword_bits - 1) {
-        // d > r
-        return 0;
-    }
-    if (sr == n_uword_bits - 1) {
-        // d == 1
-        return n;
-    }
-    sr += 1;
-    // 1 <= sr <= n_uword_bits - 1
-    // Not a special case
-    var q: u32 = n << @intCast(u5, n_uword_bits - sr);
-    var r: u32 = n >> @intCast(u5, sr);
-    var carry: u32 = 0;
-    while (sr > 0) : (sr -= 1) {
-        // r:q = ((r:q)  << 1) | carry
-        r = (r << 1) | (q >> @intCast(u5, n_uword_bits - 1));
-        q = (q << 1) | carry;
-        // carry = 0;
-        // if (r.all >= d.all)
-        // {
-        //      r.all -= d.all;
-        //      carry = 1;
-        // }
-        const s = @intCast(i32, d -% r -% 1) >> @intCast(u5, n_uword_bits - 1);
-        carry = @intCast(u32, s & 1);
-        r -= d & @bitCast(u32, s);
-    }
-    q = (q << 1) | carry;
-    return q;
-}
-
-fn __modsi3(n: i32, d: i32) callconv(.C) i32 {
-    @setRuntimeSafety(is_test);
-
-    return n -% __divsi3(n, d) *% d;
-}
-
-fn __umodsi3(n: u32, d: u32) callconv(.C) u32 {
-    @setRuntimeSafety(is_test);
-
-    return n -% __udivsi3(n, d) *% d;
-}
-
-test "test_umoddi3" {
-    test_one_umoddi3(0, 1, 0);
-    test_one_umoddi3(2, 1, 0);
-    test_one_umoddi3(0x8000000000000000, 1, 0x0);
-    test_one_umoddi3(0x8000000000000000, 2, 0x0);
-    test_one_umoddi3(0xFFFFFFFFFFFFFFFF, 2, 0x1);
-}
-
-fn test_one_umoddi3(a: u64, b: u64, expected_r: u64) void {
-    const r = __umoddi3(a, b);
-    testing.expect(r == expected_r);
-}
-
-test "test_udivsi3" {
-    const cases = [_][3]u32{
-        [_]u32{
-            0x00000000,
-            0x00000001,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0x00000002,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0x00000003,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0x00000010,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0x078644FA,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0x0747AE14,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0x7FFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000000,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0x00000001,
-            0x00000001,
-        },
-        [_]u32{
-            0x00000001,
-            0x00000002,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0x00000003,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0x00000010,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0x078644FA,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0x0747AE14,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0x7FFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000001,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0x00000001,
-            0x00000002,
-        },
-        [_]u32{
-            0x00000002,
-            0x00000002,
-            0x00000001,
-        },
-        [_]u32{
-            0x00000002,
-            0x00000003,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0x00000010,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0x078644FA,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0x0747AE14,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0x7FFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000002,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0x00000001,
-            0x00000003,
-        },
-        [_]u32{
-            0x00000003,
-            0x00000002,
-            0x00000001,
-        },
-        [_]u32{
-            0x00000003,
-            0x00000003,
-            0x00000001,
-        },
-        [_]u32{
-            0x00000003,
-            0x00000010,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0x078644FA,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0x0747AE14,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0x7FFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000003,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000010,
-            0x00000001,
-            0x00000010,
-        },
-        [_]u32{
-            0x00000010,
-            0x00000002,
-            0x00000008,
-        },
-        [_]u32{
-            0x00000010,
-            0x00000003,
-            0x00000005,
-        },
-        [_]u32{
-            0x00000010,
-            0x00000010,
-            0x00000001,
-        },
-        [_]u32{
-            0x00000010,
-            0x078644FA,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000010,
-            0x0747AE14,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000010,
-            0x7FFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000010,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000010,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000010,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x00000010,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x078644FA,
-            0x00000001,
-            0x078644FA,
-        },
-        [_]u32{
-            0x078644FA,
-            0x00000002,
-            0x03C3227D,
-        },
-        [_]u32{
-            0x078644FA,
-            0x00000003,
-            0x028216FE,
-        },
-        [_]u32{
-            0x078644FA,
-            0x00000010,
-            0x0078644F,
-        },
-        [_]u32{
-            0x078644FA,
-            0x078644FA,
-            0x00000001,
-        },
-        [_]u32{
-            0x078644FA,
-            0x0747AE14,
-            0x00000001,
-        },
-        [_]u32{
-            0x078644FA,
-            0x7FFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x078644FA,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x078644FA,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x078644FA,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x078644FA,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x00000001,
-            0x0747AE14,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x00000002,
-            0x03A3D70A,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x00000003,
-            0x026D3A06,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x00000010,
-            0x00747AE1,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x078644FA,
-            0x00000000,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x0747AE14,
-            0x00000001,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x7FFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x0747AE14,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x0747AE14,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x0747AE14,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x0747AE14,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x00000001,
-            0x7FFFFFFF,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x00000002,
-            0x3FFFFFFF,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x00000003,
-            0x2AAAAAAA,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x00000010,
-            0x07FFFFFF,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x078644FA,
-            0x00000011,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x0747AE14,
-            0x00000011,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x7FFFFFFF,
-            0x00000001,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0x80000000,
-            0x00000000,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x7FFFFFFF,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0x80000000,
-            0x00000001,
-            0x80000000,
-        },
-        [_]u32{
-            0x80000000,
-            0x00000002,
-            0x40000000,
-        },
-        [_]u32{
-            0x80000000,
-            0x00000003,
-            0x2AAAAAAA,
-        },
-        [_]u32{
-            0x80000000,
-            0x00000010,
-            0x08000000,
-        },
-        [_]u32{
-            0x80000000,
-            0x078644FA,
-            0x00000011,
-        },
-        [_]u32{
-            0x80000000,
-            0x0747AE14,
-            0x00000011,
-        },
-        [_]u32{
-            0x80000000,
-            0x7FFFFFFF,
-            0x00000001,
-        },
-        [_]u32{
-            0x80000000,
-            0x80000000,
-            0x00000001,
-        },
-        [_]u32{
-            0x80000000,
-            0xFFFFFFFD,
-            0x00000000,
-        },
-        [_]u32{
-            0x80000000,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0x80000000,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x00000001,
-            0xFFFFFFFD,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x00000002,
-            0x7FFFFFFE,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x00000003,
-            0x55555554,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x00000010,
-            0x0FFFFFFF,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x078644FA,
-            0x00000022,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x0747AE14,
-            0x00000023,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x7FFFFFFF,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0x80000000,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0xFFFFFFFD,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0xFFFFFFFE,
-            0x00000000,
-        },
-        [_]u32{
-            0xFFFFFFFD,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x00000001,
-            0xFFFFFFFE,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x00000002,
-            0x7FFFFFFF,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x00000003,
-            0x55555554,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x00000010,
-            0x0FFFFFFF,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x078644FA,
-            0x00000022,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x0747AE14,
-            0x00000023,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x7FFFFFFF,
-            0x00000002,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0x80000000,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0xFFFFFFFD,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0xFFFFFFFE,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFE,
-            0xFFFFFFFF,
-            0x00000000,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x00000001,
-            0xFFFFFFFF,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x00000002,
-            0x7FFFFFFF,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x00000003,
-            0x55555555,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x00000010,
-            0x0FFFFFFF,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x078644FA,
-            0x00000022,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x0747AE14,
-            0x00000023,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x7FFFFFFF,
-            0x00000002,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0x80000000,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0xFFFFFFFD,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0xFFFFFFFE,
-            0x00000001,
-        },
-        [_]u32{
-            0xFFFFFFFF,
-            0xFFFFFFFF,
-            0x00000001,
-        },
-    };
-
-    for (cases) |case| {
-        test_one_udivsi3(case[0], case[1], case[2]);
-    }
-}
-
-fn test_one_udivsi3(a: u32, b: u32, expected_q: u32) void {
-    const q: u32 = __udivsi3(a, b);
-    testing.expect(q == expected_q);
-}
-
-test "test_divsi3" {
-    const cases = [_][3]i32{
-        [_]i32{ 0, 1, 0 },
-        [_]i32{ 0, -1, 0 },
-        [_]i32{ 2, 1, 2 },
-        [_]i32{ 2, -1, -2 },
-        [_]i32{ -2, 1, -2 },
-        [_]i32{ -2, -1, 2 },
-
-        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), 1, @bitCast(i32, @as(u32, 0x80000000)) },
-        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), -1, @bitCast(i32, @as(u32, 0x80000000)) },
-        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), -2, 0x40000000 },
-        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), 2, @bitCast(i32, @as(u32, 0xC0000000)) },
-    };
-
-    for (cases) |case| {
-        test_one_divsi3(case[0], case[1], case[2]);
-    }
-}
-
-fn test_one_divsi3(a: i32, b: i32, expected_q: i32) void {
-    const q: i32 = __divsi3(a, b);
-    testing.expect(q == expected_q);
-}
-
-test "test_divmodsi4" {
-    const cases = [_][4]i32{
-        [_]i32{ 0, 1, 0, 0 },
-        [_]i32{ 0, -1, 0, 0 },
-        [_]i32{ 2, 1, 2, 0 },
-        [_]i32{ 2, -1, -2, 0 },
-        [_]i32{ -2, 1, -2, 0 },
-        [_]i32{ -2, -1, 2, 0 },
-        [_]i32{ 7, 5, 1, 2 },
-        [_]i32{ -7, 5, -1, -2 },
-        [_]i32{ 19, 5, 3, 4 },
-        [_]i32{ 19, -5, -3, 4 },
-
-        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), 8, @bitCast(i32, @as(u32, 0xf0000000)), 0 },
-        [_]i32{ @bitCast(i32, @as(u32, 0x80000007)), 8, @bitCast(i32, @as(u32, 0xf0000001)), -1 },
-    };
-
-    for (cases) |case| {
-        test_one_divmodsi4(case[0], case[1], case[2], case[3]);
-    }
-}
-
-fn test_one_divmodsi4(a: i32, b: i32, expected_q: i32, expected_r: i32) void {
-    var r: i32 = undefined;
-    const q: i32 = __divmodsi4(a, b, &r);
-    testing.expect(q == expected_q and r == expected_r);
-}
-
-test "test_divdi3" {
-    const cases = [_][3]i64{
-        [_]i64{ 0, 1, 0 },
-        [_]i64{ 0, -1, 0 },
-        [_]i64{ 2, 1, 2 },
-        [_]i64{ 2, -1, -2 },
-        [_]i64{ -2, 1, -2 },
-        [_]i64{ -2, -1, 2 },
-
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 1, @bitCast(i64, @as(u64, 0x8000000000000000)) },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -1, @bitCast(i64, @as(u64, 0x8000000000000000)) },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -2, 0x4000000000000000 },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 2, @bitCast(i64, @as(u64, 0xC000000000000000)) },
-    };
-
-    for (cases) |case| {
-        test_one_divdi3(case[0], case[1], case[2]);
-    }
-}
-
-fn test_one_divdi3(a: i64, b: i64, expected_q: i64) void {
-    const q: i64 = __divdi3(a, b);
-    testing.expect(q == expected_q);
-}
-
-test "test_moddi3" {
-    const cases = [_][3]i64{
-        [_]i64{ 0, 1, 0 },
-        [_]i64{ 0, -1, 0 },
-        [_]i64{ 5, 3, 2 },
-        [_]i64{ 5, -3, 2 },
-        [_]i64{ -5, 3, -2 },
-        [_]i64{ -5, -3, -2 },
-
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 1, 0 },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -1, 0 },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 2, 0 },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -2, 0 },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 3, -2 },
-        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -3, -2 },
-    };
-
-    for (cases) |case| {
-        test_one_moddi3(case[0], case[1], case[2]);
-    }
-}
-
-fn test_one_moddi3(a: i64, b: i64, expected_r: i64) void {
-    const r: i64 = __moddi3(a, b);
-    testing.expect(r == expected_r);
-}
-
-test "test_modsi3" {
-    const cases = [_][3]i32{
-        [_]i32{ 0, 1, 0 },
-        [_]i32{ 0, -1, 0 },
-        [_]i32{ 5, 3, 2 },
-        [_]i32{ 5, -3, 2 },
-        [_]i32{ -5, 3, -2 },
-        [_]i32{ -5, -3, -2 },
-        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), 1, 0x0 },
-        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), 2, 0x0 },
-        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), -2, 0x0 },
-        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), 3, -2 },
-        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), -3, -2 },
-    };
-
-    for (cases) |case| {
-        test_one_modsi3(case[0], case[1], case[2]);
-    }
-}
-
-fn test_one_modsi3(a: i32, b: i32, expected_r: i32) void {
-    const r: i32 = __modsi3(a, b);
-    testing.expect(r == expected_r);
-}
-
-test "test_umodsi3" {
-    const cases = [_][3]u32{
-        [_]u32{ 0x00000000, 0x00000001, 0x00000000 },
-        [_]u32{ 0x00000000, 0x00000002, 0x00000000 },
-        [_]u32{ 0x00000000, 0x00000003, 0x00000000 },
-        [_]u32{ 0x00000000, 0x00000010, 0x00000000 },
-        [_]u32{ 0x00000000, 0x078644FA, 0x00000000 },
-        [_]u32{ 0x00000000, 0x0747AE14, 0x00000000 },
-        [_]u32{ 0x00000000, 0x7FFFFFFF, 0x00000000 },
-        [_]u32{ 0x00000000, 0x80000000, 0x00000000 },
-        [_]u32{ 0x00000000, 0xFFFFFFFD, 0x00000000 },
-        [_]u32{ 0x00000000, 0xFFFFFFFE, 0x00000000 },
-        [_]u32{ 0x00000000, 0xFFFFFFFF, 0x00000000 },
-        [_]u32{ 0x00000001, 0x00000001, 0x00000000 },
-        [_]u32{ 0x00000001, 0x00000002, 0x00000001 },
-        [_]u32{ 0x00000001, 0x00000003, 0x00000001 },
-        [_]u32{ 0x00000001, 0x00000010, 0x00000001 },
-        [_]u32{ 0x00000001, 0x078644FA, 0x00000001 },
-        [_]u32{ 0x00000001, 0x0747AE14, 0x00000001 },
-        [_]u32{ 0x00000001, 0x7FFFFFFF, 0x00000001 },
-        [_]u32{ 0x00000001, 0x80000000, 0x00000001 },
-        [_]u32{ 0x00000001, 0xFFFFFFFD, 0x00000001 },
-        [_]u32{ 0x00000001, 0xFFFFFFFE, 0x00000001 },
-        [_]u32{ 0x00000001, 0xFFFFFFFF, 0x00000001 },
-        [_]u32{ 0x00000002, 0x00000001, 0x00000000 },
-        [_]u32{ 0x00000002, 0x00000002, 0x00000000 },
-        [_]u32{ 0x00000002, 0x00000003, 0x00000002 },
-        [_]u32{ 0x00000002, 0x00000010, 0x00000002 },
-        [_]u32{ 0x00000002, 0x078644FA, 0x00000002 },
-        [_]u32{ 0x00000002, 0x0747AE14, 0x00000002 },
-        [_]u32{ 0x00000002, 0x7FFFFFFF, 0x00000002 },
-        [_]u32{ 0x00000002, 0x80000000, 0x00000002 },
-        [_]u32{ 0x00000002, 0xFFFFFFFD, 0x00000002 },
-        [_]u32{ 0x00000002, 0xFFFFFFFE, 0x00000002 },
-        [_]u32{ 0x00000002, 0xFFFFFFFF, 0x00000002 },
-        [_]u32{ 0x00000003, 0x00000001, 0x00000000 },
-        [_]u32{ 0x00000003, 0x00000002, 0x00000001 },
-        [_]u32{ 0x00000003, 0x00000003, 0x00000000 },
-        [_]u32{ 0x00000003, 0x00000010, 0x00000003 },
-        [_]u32{ 0x00000003, 0x078644FA, 0x00000003 },
-        [_]u32{ 0x00000003, 0x0747AE14, 0x00000003 },
-        [_]u32{ 0x00000003, 0x7FFFFFFF, 0x00000003 },
-        [_]u32{ 0x00000003, 0x80000000, 0x00000003 },
-        [_]u32{ 0x00000003, 0xFFFFFFFD, 0x00000003 },
-        [_]u32{ 0x00000003, 0xFFFFFFFE, 0x00000003 },
-        [_]u32{ 0x00000003, 0xFFFFFFFF, 0x00000003 },
-        [_]u32{ 0x00000010, 0x00000001, 0x00000000 },
-        [_]u32{ 0x00000010, 0x00000002, 0x00000000 },
-        [_]u32{ 0x00000010, 0x00000003, 0x00000001 },
-        [_]u32{ 0x00000010, 0x00000010, 0x00000000 },
-        [_]u32{ 0x00000010, 0x078644FA, 0x00000010 },
-        [_]u32{ 0x00000010, 0x0747AE14, 0x00000010 },
-        [_]u32{ 0x00000010, 0x7FFFFFFF, 0x00000010 },
-        [_]u32{ 0x00000010, 0x80000000, 0x00000010 },
-        [_]u32{ 0x00000010, 0xFFFFFFFD, 0x00000010 },
-        [_]u32{ 0x00000010, 0xFFFFFFFE, 0x00000010 },
-        [_]u32{ 0x00000010, 0xFFFFFFFF, 0x00000010 },
-        [_]u32{ 0x078644FA, 0x00000001, 0x00000000 },
-        [_]u32{ 0x078644FA, 0x00000002, 0x00000000 },
-        [_]u32{ 0x078644FA, 0x00000003, 0x00000000 },
-        [_]u32{ 0x078644FA, 0x00000010, 0x0000000A },
-        [_]u32{ 0x078644FA, 0x078644FA, 0x00000000 },
-        [_]u32{ 0x078644FA, 0x0747AE14, 0x003E96E6 },
-        [_]u32{ 0x078644FA, 0x7FFFFFFF, 0x078644FA },
-        [_]u32{ 0x078644FA, 0x80000000, 0x078644FA },
-        [_]u32{ 0x078644FA, 0xFFFFFFFD, 0x078644FA },
-        [_]u32{ 0x078644FA, 0xFFFFFFFE, 0x078644FA },
-        [_]u32{ 0x078644FA, 0xFFFFFFFF, 0x078644FA },
-        [_]u32{ 0x0747AE14, 0x00000001, 0x00000000 },
-        [_]u32{ 0x0747AE14, 0x00000002, 0x00000000 },
-        [_]u32{ 0x0747AE14, 0x00000003, 0x00000002 },
-        [_]u32{ 0x0747AE14, 0x00000010, 0x00000004 },
-        [_]u32{ 0x0747AE14, 0x078644FA, 0x0747AE14 },
-        [_]u32{ 0x0747AE14, 0x0747AE14, 0x00000000 },
-        [_]u32{ 0x0747AE14, 0x7FFFFFFF, 0x0747AE14 },
-        [_]u32{ 0x0747AE14, 0x80000000, 0x0747AE14 },
-        [_]u32{ 0x0747AE14, 0xFFFFFFFD, 0x0747AE14 },
-        [_]u32{ 0x0747AE14, 0xFFFFFFFE, 0x0747AE14 },
-        [_]u32{ 0x0747AE14, 0xFFFFFFFF, 0x0747AE14 },
-        [_]u32{ 0x7FFFFFFF, 0x00000001, 0x00000000 },
-        [_]u32{ 0x7FFFFFFF, 0x00000002, 0x00000001 },
-        [_]u32{ 0x7FFFFFFF, 0x00000003, 0x00000001 },
-        [_]u32{ 0x7FFFFFFF, 0x00000010, 0x0000000F },
-        [_]u32{ 0x7FFFFFFF, 0x078644FA, 0x00156B65 },
-        [_]u32{ 0x7FFFFFFF, 0x0747AE14, 0x043D70AB },
-        [_]u32{ 0x7FFFFFFF, 0x7FFFFFFF, 0x00000000 },
-        [_]u32{ 0x7FFFFFFF, 0x80000000, 0x7FFFFFFF },
-        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFD, 0x7FFFFFFF },
-        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFE, 0x7FFFFFFF },
-        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFF, 0x7FFFFFFF },
-        [_]u32{ 0x80000000, 0x00000001, 0x00000000 },
-        [_]u32{ 0x80000000, 0x00000002, 0x00000000 },
-        [_]u32{ 0x80000000, 0x00000003, 0x00000002 },
-        [_]u32{ 0x80000000, 0x00000010, 0x00000000 },
-        [_]u32{ 0x80000000, 0x078644FA, 0x00156B66 },
-        [_]u32{ 0x80000000, 0x0747AE14, 0x043D70AC },
-        [_]u32{ 0x80000000, 0x7FFFFFFF, 0x00000001 },
-        [_]u32{ 0x80000000, 0x80000000, 0x00000000 },
-        [_]u32{ 0x80000000, 0xFFFFFFFD, 0x80000000 },
-        [_]u32{ 0x80000000, 0xFFFFFFFE, 0x80000000 },
-        [_]u32{ 0x80000000, 0xFFFFFFFF, 0x80000000 },
-        [_]u32{ 0xFFFFFFFD, 0x00000001, 0x00000000 },
-        [_]u32{ 0xFFFFFFFD, 0x00000002, 0x00000001 },
-        [_]u32{ 0xFFFFFFFD, 0x00000003, 0x00000001 },
-        [_]u32{ 0xFFFFFFFD, 0x00000010, 0x0000000D },
-        [_]u32{ 0xFFFFFFFD, 0x078644FA, 0x002AD6C9 },
-        [_]u32{ 0xFFFFFFFD, 0x0747AE14, 0x01333341 },
-        [_]u32{ 0xFFFFFFFD, 0x7FFFFFFF, 0x7FFFFFFE },
-        [_]u32{ 0xFFFFFFFD, 0x80000000, 0x7FFFFFFD },
-        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFD, 0x00000000 },
-        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFE, 0xFFFFFFFD },
-        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFF, 0xFFFFFFFD },
-        [_]u32{ 0xFFFFFFFE, 0x00000001, 0x00000000 },
-        [_]u32{ 0xFFFFFFFE, 0x00000002, 0x00000000 },
-        [_]u32{ 0xFFFFFFFE, 0x00000003, 0x00000002 },
-        [_]u32{ 0xFFFFFFFE, 0x00000010, 0x0000000E },
-        [_]u32{ 0xFFFFFFFE, 0x078644FA, 0x002AD6CA },
-        [_]u32{ 0xFFFFFFFE, 0x0747AE14, 0x01333342 },
-        [_]u32{ 0xFFFFFFFE, 0x7FFFFFFF, 0x00000000 },
-        [_]u32{ 0xFFFFFFFE, 0x80000000, 0x7FFFFFFE },
-        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFD, 0x00000001 },
-        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFE, 0x00000000 },
-        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFF, 0xFFFFFFFE },
-        [_]u32{ 0xFFFFFFFF, 0x00000001, 0x00000000 },
-        [_]u32{ 0xFFFFFFFF, 0x00000002, 0x00000001 },
-        [_]u32{ 0xFFFFFFFF, 0x00000003, 0x00000000 },
-        [_]u32{ 0xFFFFFFFF, 0x00000010, 0x0000000F },
-        [_]u32{ 0xFFFFFFFF, 0x078644FA, 0x002AD6CB },
-        [_]u32{ 0xFFFFFFFF, 0x0747AE14, 0x01333343 },
-        [_]u32{ 0xFFFFFFFF, 0x7FFFFFFF, 0x00000001 },
-        [_]u32{ 0xFFFFFFFF, 0x80000000, 0x7FFFFFFF },
-        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFD, 0x00000002 },
-        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFE, 0x00000001 },
-        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFF, 0x00000000 },
-    };
-
-    for (cases) |case| {
-        test_one_umodsi3(case[0], case[1], case[2]);
-    }
-}
-
-fn test_one_umodsi3(a: u32, b: u32, expected_r: u32) void {
-    const r: u32 = __umodsi3(a, b);
-    testing.expect(r == expected_r);
-}
diff --git a/lib/std/special/compiler_rt/arm.zig b/lib/std/special/compiler_rt/arm.zig
new file mode 100644
index 0000000000..9ba423931b
--- /dev/null
+++ b/lib/std/special/compiler_rt/arm.zig
@@ -0,0 +1,128 @@
+// ARM specific builtins
+const builtin = @import("builtin");
+const is_test = builtin.is_test;
+
+const __divmodsi4 = @import("int.zig").__divmodsi4;
+const __udivmodsi4 = @import("int.zig").__udivmodsi4;
+const __divmoddi4 = @import("int.zig").__divmoddi4;
+const __udivmoddi4 = @import("int.zig").__udivmoddi4;
+
+extern fn memset(dest: ?[*]u8, c: u8, n: usize) ?[*]u8;
+extern fn memcpy(noalias dest: ?[*]u8, noalias src: ?[*]const u8, n: usize) ?[*]u8;
+extern fn memmove(dest: ?[*]u8, src: ?[*]const u8, n: usize) ?[*]u8;
+
+pub fn __aeabi_memcpy(dest: [*]u8, src: [*]u8, n: usize) callconv(.AAPCS) void {
+    @setRuntimeSafety(false);
+    _ = memcpy(dest, src, n);
+}
+
+pub fn __aeabi_memmove(dest: [*]u8, src: [*]u8, n: usize) callconv(.AAPCS) void {
+    @setRuntimeSafety(false);
+    _ = memmove(dest, src, n);
+}
+
+pub fn __aeabi_memset(dest: [*]u8, n: usize, c: u8) callconv(.AAPCS) void {
+    @setRuntimeSafety(false);
+    // This is dentical to the standard `memset` definition but with the last
+    // two arguments swapped
+    _ = memset(dest, c, n);
+}
+
+pub fn __aeabi_memclr(dest: [*]u8, n: usize) callconv(.AAPCS) void {
+    @setRuntimeSafety(false);
+    _ = memset(dest, 0, n);
+}
+
+pub fn __aeabi_unwind_cpp_pr0() callconv(.C) void {
+    unreachable;
+}
+pub fn __aeabi_unwind_cpp_pr1() callconv(.C) void {
+    unreachable;
+}
+pub fn __aeabi_unwind_cpp_pr2() callconv(.C) void {
+    unreachable;
+}
+
+// This function can only clobber r0 according to the ABI
+pub fn __aeabi_read_tp() callconv(.Naked) void {
+    asm volatile (
+        \\ mrc p15, 0, r0, c13, c0, 3
+        \\ bx lr
+    );
+    unreachable;
+}
+
+// The following functions are wrapped in an asm block to ensure the required
+// calling convention is always respected
+
+pub fn __aeabi_uidivmod() callconv(.Naked) void {
+    // Divide r0 by r1; the quotient goes in r0, the remainder in r1
+    asm volatile (
+        \\ push {lr}
+        \\ sub sp, #4
+        \\ mov r2, sp
+        \\ bl  __udivmodsi4
+        \\ ldr r1, [sp]
+        \\ add sp, #4
+        \\ pop {pc}
+        :
+        :
+        : "memory"
+    );
+    unreachable;
+}
+
+pub fn __aeabi_uldivmod() callconv(.Naked) void {
+    // Divide r1:r0 by r3:r2; the quotient goes in r1:r0, the remainder in r3:r2
+    asm volatile (
+        \\ push {r4, lr}
+        \\ sub sp, #16
+        \\ add r4, sp, #8
+        \\ str r4, [sp]
+        \\ bl  __udivmoddi4
+        \\ ldr r2, [sp, #8]
+        \\ ldr r3, [sp, #12]
+        \\ add sp, #16
+        \\ pop {r4, pc}
+        :
+        :
+        : "memory"
+    );
+    unreachable;
+}
+
+pub fn __aeabi_idivmod() callconv(.Naked) void {
+    // Divide r0 by r1; the quotient goes in r0, the remainder in r1
+    asm volatile (
+        \\ push {lr}
+        \\ sub sp, #4
+        \\ mov r2, sp
+        \\ bl  __divmodsi4
+        \\ ldr r1, [sp]
+        \\ add sp, #4
+        \\ pop {pc}
+        :
+        :
+        : "memory"
+    );
+    unreachable;
+}
+
+pub fn __aeabi_ldivmod() callconv(.Naked) void {
+    // Divide r1:r0 by r3:r2; the quotient goes in r1:r0, the remainder in r3:r2
+    asm volatile (
+        \\ push {r4, lr}
+        \\ sub sp, #16
+        \\ add r4, sp, #8
+        \\ str r4, [sp]
+        \\ bl  __divmoddi4
+        \\ ldr r2, [sp, #8]
+        \\ ldr r3, [sp, #12]
+        \\ add sp, #16
+        \\ pop {r4, pc}
+        :
+        :
+        : "memory"
+    );
+    unreachable;
+}
diff --git a/lib/std/special/compiler_rt/int.zig b/lib/std/special/compiler_rt/int.zig
new file mode 100644
index 0000000000..88f4d66966
--- /dev/null
+++ b/lib/std/special/compiler_rt/int.zig
@@ -0,0 +1,580 @@
+// Builtin functions that operate on integer types
+const builtin = @import("builtin");
+const testing = @import("std").testing;
+
+const udivmod = @import("udivmod.zig").udivmod;
+
+pub fn __divmoddi4(a: i64, b: i64, rem: *i64) callconv(.C) i64 {
+    @setRuntimeSafety(builtin.is_test);
+
+    const d = __divdi3(a, b);
+    rem.* = a -% (d *% b);
+    return d;
+}
+
+pub fn __udivmoddi4(a: u64, b: u64, maybe_rem: ?*u64) callconv(.C) u64 {
+    @setRuntimeSafety(builtin.is_test);
+    return udivmod(u64, a, b, maybe_rem);
+}
+
+test "test_udivmoddi4" {
+    _ = @import("udivmoddi4_test.zig");
+}
+
+pub fn __divdi3(a: i64, b: i64) callconv(.C) i64 {
+    @setRuntimeSafety(builtin.is_test);
+
+    // Set aside the sign of the quotient.
+    const sign = @bitCast(u64, (a ^ b) >> 63);
+    // Take absolute value of a and b via abs(x) = (x^(x >> 63)) - (x >> 63).
+    const abs_a = (a ^ (a >> 63)) -% (a >> 63);
+    const abs_b = (b ^ (b >> 63)) -% (b >> 63);
+    // Unsigned division
+    const res = __udivmoddi4(@bitCast(u64, abs_a), @bitCast(u64, abs_b), null);
+    // Apply sign of quotient to result and return.
+    return @bitCast(i64, (res ^ sign) -% sign);
+}
+
+test "test_divdi3" {
+    const cases = [_][3]i64{
+        [_]i64{ 0, 1, 0 },
+        [_]i64{ 0, -1, 0 },
+        [_]i64{ 2, 1, 2 },
+        [_]i64{ 2, -1, -2 },
+        [_]i64{ -2, 1, -2 },
+        [_]i64{ -2, -1, 2 },
+
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 1, @bitCast(i64, @as(u64, 0x8000000000000000)) },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -1, @bitCast(i64, @as(u64, 0x8000000000000000)) },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -2, 0x4000000000000000 },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 2, @bitCast(i64, @as(u64, 0xC000000000000000)) },
+    };
+
+    for (cases) |case| {
+        test_one_divdi3(case[0], case[1], case[2]);
+    }
+}
+
+fn test_one_divdi3(a: i64, b: i64, expected_q: i64) void {
+    const q: i64 = __divdi3(a, b);
+    testing.expect(q == expected_q);
+}
+
+pub fn __moddi3(a: i64, b: i64) callconv(.C) i64 {
+    @setRuntimeSafety(builtin.is_test);
+
+    // Take absolute value of a and b via abs(x) = (x^(x >> 63)) - (x >> 63).
+    const abs_a = (a ^ (a >> 63)) -% (a >> 63);
+    const abs_b = (b ^ (b >> 63)) -% (b >> 63);
+    // Unsigned division
+    var r: u64 = undefined;
+    _ = __udivmoddi4(@bitCast(u64, abs_a), @bitCast(u64, abs_b), &r);
+    // Apply the sign of the dividend and return.
+    return (@bitCast(i64, r) ^ (a >> 63)) -% (a >> 63);
+}
+
+test "test_moddi3" {
+    const cases = [_][3]i64{
+        [_]i64{ 0, 1, 0 },
+        [_]i64{ 0, -1, 0 },
+        [_]i64{ 5, 3, 2 },
+        [_]i64{ 5, -3, 2 },
+        [_]i64{ -5, 3, -2 },
+        [_]i64{ -5, -3, -2 },
+
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 1, 0 },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -1, 0 },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 2, 0 },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -2, 0 },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), 3, -2 },
+        [_]i64{ @bitCast(i64, @as(u64, 0x8000000000000000)), -3, -2 },
+    };
+
+    for (cases) |case| {
+        test_one_moddi3(case[0], case[1], case[2]);
+    }
+}
+
+fn test_one_moddi3(a: i64, b: i64, expected_r: i64) void {
+    const r: i64 = __moddi3(a, b);
+    testing.expect(r == expected_r);
+}
+
+pub fn __udivdi3(a: u64, b: u64) callconv(.C) u64 {
+    @setRuntimeSafety(builtin.is_test);
+    return __udivmoddi4(a, b, null);
+}
+
+pub fn __umoddi3(a: u64, b: u64) callconv(.C) u64 {
+    @setRuntimeSafety(builtin.is_test);
+
+    var r: u64 = undefined;
+    _ = __udivmoddi4(a, b, &r);
+    return r;
+}
+
+test "test_umoddi3" {
+    test_one_umoddi3(0, 1, 0);
+    test_one_umoddi3(2, 1, 0);
+    test_one_umoddi3(0x8000000000000000, 1, 0x0);
+    test_one_umoddi3(0x8000000000000000, 2, 0x0);
+    test_one_umoddi3(0xFFFFFFFFFFFFFFFF, 2, 0x1);
+}
+
+fn test_one_umoddi3(a: u64, b: u64, expected_r: u64) void {
+    const r = __umoddi3(a, b);
+    testing.expect(r == expected_r);
+}
+
+pub fn __divmodsi4(a: i32, b: i32, rem: *i32) callconv(.C) i32 {
+    @setRuntimeSafety(builtin.is_test);
+
+    const d = __divsi3(a, b);
+    rem.* = a -% (d * b);
+    return d;
+}
+
+test "test_divmodsi4" {
+    const cases = [_][4]i32{
+        [_]i32{ 0, 1, 0, 0 },
+        [_]i32{ 0, -1, 0, 0 },
+        [_]i32{ 2, 1, 2, 0 },
+        [_]i32{ 2, -1, -2, 0 },
+        [_]i32{ -2, 1, -2, 0 },
+        [_]i32{ -2, -1, 2, 0 },
+        [_]i32{ 7, 5, 1, 2 },
+        [_]i32{ -7, 5, -1, -2 },
+        [_]i32{ 19, 5, 3, 4 },
+        [_]i32{ 19, -5, -3, 4 },
+
+        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), 8, @bitCast(i32, @as(u32, 0xf0000000)), 0 },
+        [_]i32{ @bitCast(i32, @as(u32, 0x80000007)), 8, @bitCast(i32, @as(u32, 0xf0000001)), -1 },
+    };
+
+    for (cases) |case| {
+        test_one_divmodsi4(case[0], case[1], case[2], case[3]);
+    }
+}
+
+fn test_one_divmodsi4(a: i32, b: i32, expected_q: i32, expected_r: i32) void {
+    var r: i32 = undefined;
+    const q: i32 = __divmodsi4(a, b, &r);
+    testing.expect(q == expected_q and r == expected_r);
+}
+
+pub fn __udivmodsi4(a: u32, b: u32, rem: *u32) callconv(.C) u32 {
+    @setRuntimeSafety(builtin.is_test);
+
+    const d = __udivsi3(a, b);
+    rem.* = @bitCast(u32, @bitCast(i32, a) -% (@bitCast(i32, d) * @bitCast(i32, b)));
+    return d;
+}
+
+pub fn __divsi3(n: i32, d: i32) callconv(.C) i32 {
+    @setRuntimeSafety(builtin.is_test);
+
+    // Set aside the sign of the quotient.
+    const sign = @bitCast(u32, (n ^ d) >> 31);
+    // Take absolute value of a and b via abs(x) = (x^(x >> 31)) - (x >> 31).
+    const abs_n = (n ^ (n >> 31)) -% (n >> 31);
+    const abs_d = (d ^ (d >> 31)) -% (d >> 31);
+    // abs(a) / abs(b)
+    const res = @bitCast(u32, abs_n) / @bitCast(u32, abs_d);
+    // Apply sign of quotient to result and return.
+    return @bitCast(i32, (res ^ sign) -% sign);
+}
+
+test "test_divsi3" {
+    const cases = [_][3]i32{
+        [_]i32{ 0, 1, 0 },
+        [_]i32{ 0, -1, 0 },
+        [_]i32{ 2, 1, 2 },
+        [_]i32{ 2, -1, -2 },
+        [_]i32{ -2, 1, -2 },
+        [_]i32{ -2, -1, 2 },
+
+        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), 1, @bitCast(i32, @as(u32, 0x80000000)) },
+        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), -1, @bitCast(i32, @as(u32, 0x80000000)) },
+        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), -2, 0x40000000 },
+        [_]i32{ @bitCast(i32, @as(u32, 0x80000000)), 2, @bitCast(i32, @as(u32, 0xC0000000)) },
+    };
+
+    for (cases) |case| {
+        test_one_divsi3(case[0], case[1], case[2]);
+    }
+}
+
+fn test_one_divsi3(a: i32, b: i32, expected_q: i32) void {
+    const q: i32 = __divsi3(a, b);
+    testing.expect(q == expected_q);
+}
+
+pub fn __udivsi3(n: u32, d: u32) callconv(.C) u32 {
+    @setRuntimeSafety(builtin.is_test);
+
+    const n_uword_bits: c_uint = u32.bit_count;
+    // special cases
+    if (d == 0) return 0; // ?!
+    if (n == 0) return 0;
+    var sr = @bitCast(c_uint, @as(c_int, @clz(u32, d)) - @as(c_int, @clz(u32, n)));
+    // 0 <= sr <= n_uword_bits - 1 or sr large
+    if (sr > n_uword_bits - 1) {
+        // d > r
+        return 0;
+    }
+    if (sr == n_uword_bits - 1) {
+        // d == 1
+        return n;
+    }
+    sr += 1;
+    // 1 <= sr <= n_uword_bits - 1
+    // Not a special case
+    var q: u32 = n << @intCast(u5, n_uword_bits - sr);
+    var r: u32 = n >> @intCast(u5, sr);
+    var carry: u32 = 0;
+    while (sr > 0) : (sr -= 1) {
+        // r:q = ((r:q)  << 1) | carry
+        r = (r << 1) | (q >> @intCast(u5, n_uword_bits - 1));
+        q = (q << 1) | carry;
+        // carry = 0;
+        // if (r.all >= d.all)
+        // {
+        //      r.all -= d.all;
+        //      carry = 1;
+        // }
+        const s = @intCast(i32, d -% r -% 1) >> @intCast(u5, n_uword_bits - 1);
+        carry = @intCast(u32, s & 1);
+        r -= d & @bitCast(u32, s);
+    }
+    q = (q << 1) | carry;
+    return q;
+}
+
+test "test_udivsi3" {
+    const cases = [_][3]u32{
+        [_]u32{ 0x00000000, 0x00000001, 0x00000000 },
+        [_]u32{ 0x00000000, 0x00000002, 0x00000000 },
+        [_]u32{ 0x00000000, 0x00000003, 0x00000000 },
+        [_]u32{ 0x00000000, 0x00000010, 0x00000000 },
+        [_]u32{ 0x00000000, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x00000000, 0x0747AE14, 0x00000000 },
+        [_]u32{ 0x00000000, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000000, 0x80000000, 0x00000000 },
+        [_]u32{ 0x00000000, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x00000000, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x00000000, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000001, 0x00000001, 0x00000001 },
+        [_]u32{ 0x00000001, 0x00000002, 0x00000000 },
+        [_]u32{ 0x00000001, 0x00000003, 0x00000000 },
+        [_]u32{ 0x00000001, 0x00000010, 0x00000000 },
+        [_]u32{ 0x00000001, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x00000001, 0x0747AE14, 0x00000000 },
+        [_]u32{ 0x00000001, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000001, 0x80000000, 0x00000000 },
+        [_]u32{ 0x00000001, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x00000001, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x00000001, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000002, 0x00000001, 0x00000002 },
+        [_]u32{ 0x00000002, 0x00000002, 0x00000001 },
+        [_]u32{ 0x00000002, 0x00000003, 0x00000000 },
+        [_]u32{ 0x00000002, 0x00000010, 0x00000000 },
+        [_]u32{ 0x00000002, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x00000002, 0x0747AE14, 0x00000000 },
+        [_]u32{ 0x00000002, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000002, 0x80000000, 0x00000000 },
+        [_]u32{ 0x00000002, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x00000002, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x00000002, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000003, 0x00000001, 0x00000003 },
+        [_]u32{ 0x00000003, 0x00000002, 0x00000001 },
+        [_]u32{ 0x00000003, 0x00000003, 0x00000001 },
+        [_]u32{ 0x00000003, 0x00000010, 0x00000000 },
+        [_]u32{ 0x00000003, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x00000003, 0x0747AE14, 0x00000000 },
+        [_]u32{ 0x00000003, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000003, 0x80000000, 0x00000000 },
+        [_]u32{ 0x00000003, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x00000003, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x00000003, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000010, 0x00000001, 0x00000010 },
+        [_]u32{ 0x00000010, 0x00000002, 0x00000008 },
+        [_]u32{ 0x00000010, 0x00000003, 0x00000005 },
+        [_]u32{ 0x00000010, 0x00000010, 0x00000001 },
+        [_]u32{ 0x00000010, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x00000010, 0x0747AE14, 0x00000000 },
+        [_]u32{ 0x00000010, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000010, 0x80000000, 0x00000000 },
+        [_]u32{ 0x00000010, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x00000010, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x00000010, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x078644FA, 0x00000001, 0x078644FA },
+        [_]u32{ 0x078644FA, 0x00000002, 0x03C3227D },
+        [_]u32{ 0x078644FA, 0x00000003, 0x028216FE },
+        [_]u32{ 0x078644FA, 0x00000010, 0x0078644F },
+        [_]u32{ 0x078644FA, 0x078644FA, 0x00000001 },
+        [_]u32{ 0x078644FA, 0x0747AE14, 0x00000001 },
+        [_]u32{ 0x078644FA, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x078644FA, 0x80000000, 0x00000000 },
+        [_]u32{ 0x078644FA, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x078644FA, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x078644FA, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0x00000001, 0x0747AE14 },
+        [_]u32{ 0x0747AE14, 0x00000002, 0x03A3D70A },
+        [_]u32{ 0x0747AE14, 0x00000003, 0x026D3A06 },
+        [_]u32{ 0x0747AE14, 0x00000010, 0x00747AE1 },
+        [_]u32{ 0x0747AE14, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0x0747AE14, 0x00000001 },
+        [_]u32{ 0x0747AE14, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0x80000000, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x7FFFFFFF, 0x00000001, 0x7FFFFFFF },
+        [_]u32{ 0x7FFFFFFF, 0x00000002, 0x3FFFFFFF },
+        [_]u32{ 0x7FFFFFFF, 0x00000003, 0x2AAAAAAA },
+        [_]u32{ 0x7FFFFFFF, 0x00000010, 0x07FFFFFF },
+        [_]u32{ 0x7FFFFFFF, 0x078644FA, 0x00000011 },
+        [_]u32{ 0x7FFFFFFF, 0x0747AE14, 0x00000011 },
+        [_]u32{ 0x7FFFFFFF, 0x7FFFFFFF, 0x00000001 },
+        [_]u32{ 0x7FFFFFFF, 0x80000000, 0x00000000 },
+        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x80000000, 0x00000001, 0x80000000 },
+        [_]u32{ 0x80000000, 0x00000002, 0x40000000 },
+        [_]u32{ 0x80000000, 0x00000003, 0x2AAAAAAA },
+        [_]u32{ 0x80000000, 0x00000010, 0x08000000 },
+        [_]u32{ 0x80000000, 0x078644FA, 0x00000011 },
+        [_]u32{ 0x80000000, 0x0747AE14, 0x00000011 },
+        [_]u32{ 0x80000000, 0x7FFFFFFF, 0x00000001 },
+        [_]u32{ 0x80000000, 0x80000000, 0x00000001 },
+        [_]u32{ 0x80000000, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x80000000, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x80000000, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0xFFFFFFFD, 0x00000001, 0xFFFFFFFD },
+        [_]u32{ 0xFFFFFFFD, 0x00000002, 0x7FFFFFFE },
+        [_]u32{ 0xFFFFFFFD, 0x00000003, 0x55555554 },
+        [_]u32{ 0xFFFFFFFD, 0x00000010, 0x0FFFFFFF },
+        [_]u32{ 0xFFFFFFFD, 0x078644FA, 0x00000022 },
+        [_]u32{ 0xFFFFFFFD, 0x0747AE14, 0x00000023 },
+        [_]u32{ 0xFFFFFFFD, 0x7FFFFFFF, 0x00000001 },
+        [_]u32{ 0xFFFFFFFD, 0x80000000, 0x00000001 },
+        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFD, 0x00000001 },
+        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0xFFFFFFFE, 0x00000001, 0xFFFFFFFE },
+        [_]u32{ 0xFFFFFFFE, 0x00000002, 0x7FFFFFFF },
+        [_]u32{ 0xFFFFFFFE, 0x00000003, 0x55555554 },
+        [_]u32{ 0xFFFFFFFE, 0x00000010, 0x0FFFFFFF },
+        [_]u32{ 0xFFFFFFFE, 0x078644FA, 0x00000022 },
+        [_]u32{ 0xFFFFFFFE, 0x0747AE14, 0x00000023 },
+        [_]u32{ 0xFFFFFFFE, 0x7FFFFFFF, 0x00000002 },
+        [_]u32{ 0xFFFFFFFE, 0x80000000, 0x00000001 },
+        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFD, 0x00000001 },
+        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFE, 0x00000001 },
+        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0xFFFFFFFF, 0x00000001, 0xFFFFFFFF },
+        [_]u32{ 0xFFFFFFFF, 0x00000002, 0x7FFFFFFF },
+        [_]u32{ 0xFFFFFFFF, 0x00000003, 0x55555555 },
+        [_]u32{ 0xFFFFFFFF, 0x00000010, 0x0FFFFFFF },
+        [_]u32{ 0xFFFFFFFF, 0x078644FA, 0x00000022 },
+        [_]u32{ 0xFFFFFFFF, 0x0747AE14, 0x00000023 },
+        [_]u32{ 0xFFFFFFFF, 0x7FFFFFFF, 0x00000002 },
+        [_]u32{ 0xFFFFFFFF, 0x80000000, 0x00000001 },
+        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFD, 0x00000001 },
+        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFE, 0x00000001 },
+        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFF, 0x00000001 },
+    };
+
+    for (cases) |case| {
+        test_one_udivsi3(case[0], case[1], case[2]);
+    }
+}
+
+fn test_one_udivsi3(a: u32, b: u32, expected_q: u32) void {
+    const q: u32 = __udivsi3(a, b);
+    testing.expect(q == expected_q);
+}
+
+pub fn __modsi3(n: i32, d: i32) callconv(.C) i32 {
+    @setRuntimeSafety(builtin.is_test);
+
+    return n -% __divsi3(n, d) *% d;
+}
+
+test "test_modsi3" {
+    const cases = [_][3]i32{
+        [_]i32{ 0, 1, 0 },
+        [_]i32{ 0, -1, 0 },
+        [_]i32{ 5, 3, 2 },
+        [_]i32{ 5, -3, 2 },
+        [_]i32{ -5, 3, -2 },
+        [_]i32{ -5, -3, -2 },
+        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), 1, 0x0 },
+        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), 2, 0x0 },
+        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), -2, 0x0 },
+        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), 3, -2 },
+        [_]i32{ @bitCast(i32, @intCast(u32, 0x80000000)), -3, -2 },
+    };
+
+    for (cases) |case| {
+        test_one_modsi3(case[0], case[1], case[2]);
+    }
+}
+
+fn test_one_modsi3(a: i32, b: i32, expected_r: i32) void {
+    const r: i32 = __modsi3(a, b);
+    testing.expect(r == expected_r);
+}
+
+pub fn __umodsi3(n: u32, d: u32) callconv(.C) u32 {
+    @setRuntimeSafety(builtin.is_test);
+
+    return n -% __udivsi3(n, d) *% d;
+}
+
+test "test_umodsi3" {
+    const cases = [_][3]u32{
+        [_]u32{ 0x00000000, 0x00000001, 0x00000000 },
+        [_]u32{ 0x00000000, 0x00000002, 0x00000000 },
+        [_]u32{ 0x00000000, 0x00000003, 0x00000000 },
+        [_]u32{ 0x00000000, 0x00000010, 0x00000000 },
+        [_]u32{ 0x00000000, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x00000000, 0x0747AE14, 0x00000000 },
+        [_]u32{ 0x00000000, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000000, 0x80000000, 0x00000000 },
+        [_]u32{ 0x00000000, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0x00000000, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0x00000000, 0xFFFFFFFF, 0x00000000 },
+        [_]u32{ 0x00000001, 0x00000001, 0x00000000 },
+        [_]u32{ 0x00000001, 0x00000002, 0x00000001 },
+        [_]u32{ 0x00000001, 0x00000003, 0x00000001 },
+        [_]u32{ 0x00000001, 0x00000010, 0x00000001 },
+        [_]u32{ 0x00000001, 0x078644FA, 0x00000001 },
+        [_]u32{ 0x00000001, 0x0747AE14, 0x00000001 },
+        [_]u32{ 0x00000001, 0x7FFFFFFF, 0x00000001 },
+        [_]u32{ 0x00000001, 0x80000000, 0x00000001 },
+        [_]u32{ 0x00000001, 0xFFFFFFFD, 0x00000001 },
+        [_]u32{ 0x00000001, 0xFFFFFFFE, 0x00000001 },
+        [_]u32{ 0x00000001, 0xFFFFFFFF, 0x00000001 },
+        [_]u32{ 0x00000002, 0x00000001, 0x00000000 },
+        [_]u32{ 0x00000002, 0x00000002, 0x00000000 },
+        [_]u32{ 0x00000002, 0x00000003, 0x00000002 },
+        [_]u32{ 0x00000002, 0x00000010, 0x00000002 },
+        [_]u32{ 0x00000002, 0x078644FA, 0x00000002 },
+        [_]u32{ 0x00000002, 0x0747AE14, 0x00000002 },
+        [_]u32{ 0x00000002, 0x7FFFFFFF, 0x00000002 },
+        [_]u32{ 0x00000002, 0x80000000, 0x00000002 },
+        [_]u32{ 0x00000002, 0xFFFFFFFD, 0x00000002 },
+        [_]u32{ 0x00000002, 0xFFFFFFFE, 0x00000002 },
+        [_]u32{ 0x00000002, 0xFFFFFFFF, 0x00000002 },
+        [_]u32{ 0x00000003, 0x00000001, 0x00000000 },
+        [_]u32{ 0x00000003, 0x00000002, 0x00000001 },
+        [_]u32{ 0x00000003, 0x00000003, 0x00000000 },
+        [_]u32{ 0x00000003, 0x00000010, 0x00000003 },
+        [_]u32{ 0x00000003, 0x078644FA, 0x00000003 },
+        [_]u32{ 0x00000003, 0x0747AE14, 0x00000003 },
+        [_]u32{ 0x00000003, 0x7FFFFFFF, 0x00000003 },
+        [_]u32{ 0x00000003, 0x80000000, 0x00000003 },
+        [_]u32{ 0x00000003, 0xFFFFFFFD, 0x00000003 },
+        [_]u32{ 0x00000003, 0xFFFFFFFE, 0x00000003 },
+        [_]u32{ 0x00000003, 0xFFFFFFFF, 0x00000003 },
+        [_]u32{ 0x00000010, 0x00000001, 0x00000000 },
+        [_]u32{ 0x00000010, 0x00000002, 0x00000000 },
+        [_]u32{ 0x00000010, 0x00000003, 0x00000001 },
+        [_]u32{ 0x00000010, 0x00000010, 0x00000000 },
+        [_]u32{ 0x00000010, 0x078644FA, 0x00000010 },
+        [_]u32{ 0x00000010, 0x0747AE14, 0x00000010 },
+        [_]u32{ 0x00000010, 0x7FFFFFFF, 0x00000010 },
+        [_]u32{ 0x00000010, 0x80000000, 0x00000010 },
+        [_]u32{ 0x00000010, 0xFFFFFFFD, 0x00000010 },
+        [_]u32{ 0x00000010, 0xFFFFFFFE, 0x00000010 },
+        [_]u32{ 0x00000010, 0xFFFFFFFF, 0x00000010 },
+        [_]u32{ 0x078644FA, 0x00000001, 0x00000000 },
+        [_]u32{ 0x078644FA, 0x00000002, 0x00000000 },
+        [_]u32{ 0x078644FA, 0x00000003, 0x00000000 },
+        [_]u32{ 0x078644FA, 0x00000010, 0x0000000A },
+        [_]u32{ 0x078644FA, 0x078644FA, 0x00000000 },
+        [_]u32{ 0x078644FA, 0x0747AE14, 0x003E96E6 },
+        [_]u32{ 0x078644FA, 0x7FFFFFFF, 0x078644FA },
+        [_]u32{ 0x078644FA, 0x80000000, 0x078644FA },
+        [_]u32{ 0x078644FA, 0xFFFFFFFD, 0x078644FA },
+        [_]u32{ 0x078644FA, 0xFFFFFFFE, 0x078644FA },
+        [_]u32{ 0x078644FA, 0xFFFFFFFF, 0x078644FA },
+        [_]u32{ 0x0747AE14, 0x00000001, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0x00000002, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0x00000003, 0x00000002 },
+        [_]u32{ 0x0747AE14, 0x00000010, 0x00000004 },
+        [_]u32{ 0x0747AE14, 0x078644FA, 0x0747AE14 },
+        [_]u32{ 0x0747AE14, 0x0747AE14, 0x00000000 },
+        [_]u32{ 0x0747AE14, 0x7FFFFFFF, 0x0747AE14 },
+        [_]u32{ 0x0747AE14, 0x80000000, 0x0747AE14 },
+        [_]u32{ 0x0747AE14, 0xFFFFFFFD, 0x0747AE14 },
+        [_]u32{ 0x0747AE14, 0xFFFFFFFE, 0x0747AE14 },
+        [_]u32{ 0x0747AE14, 0xFFFFFFFF, 0x0747AE14 },
+        [_]u32{ 0x7FFFFFFF, 0x00000001, 0x00000000 },
+        [_]u32{ 0x7FFFFFFF, 0x00000002, 0x00000001 },
+        [_]u32{ 0x7FFFFFFF, 0x00000003, 0x00000001 },
+        [_]u32{ 0x7FFFFFFF, 0x00000010, 0x0000000F },
+        [_]u32{ 0x7FFFFFFF, 0x078644FA, 0x00156B65 },
+        [_]u32{ 0x7FFFFFFF, 0x0747AE14, 0x043D70AB },
+        [_]u32{ 0x7FFFFFFF, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0x7FFFFFFF, 0x80000000, 0x7FFFFFFF },
+        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFD, 0x7FFFFFFF },
+        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFE, 0x7FFFFFFF },
+        [_]u32{ 0x7FFFFFFF, 0xFFFFFFFF, 0x7FFFFFFF },
+        [_]u32{ 0x80000000, 0x00000001, 0x00000000 },
+        [_]u32{ 0x80000000, 0x00000002, 0x00000000 },
+        [_]u32{ 0x80000000, 0x00000003, 0x00000002 },
+        [_]u32{ 0x80000000, 0x00000010, 0x00000000 },
+        [_]u32{ 0x80000000, 0x078644FA, 0x00156B66 },
+        [_]u32{ 0x80000000, 0x0747AE14, 0x043D70AC },
+        [_]u32{ 0x80000000, 0x7FFFFFFF, 0x00000001 },
+        [_]u32{ 0x80000000, 0x80000000, 0x00000000 },
+        [_]u32{ 0x80000000, 0xFFFFFFFD, 0x80000000 },
+        [_]u32{ 0x80000000, 0xFFFFFFFE, 0x80000000 },
+        [_]u32{ 0x80000000, 0xFFFFFFFF, 0x80000000 },
+        [_]u32{ 0xFFFFFFFD, 0x00000001, 0x00000000 },
+        [_]u32{ 0xFFFFFFFD, 0x00000002, 0x00000001 },
+        [_]u32{ 0xFFFFFFFD, 0x00000003, 0x00000001 },
+        [_]u32{ 0xFFFFFFFD, 0x00000010, 0x0000000D },
+        [_]u32{ 0xFFFFFFFD, 0x078644FA, 0x002AD6C9 },
+        [_]u32{ 0xFFFFFFFD, 0x0747AE14, 0x01333341 },
+        [_]u32{ 0xFFFFFFFD, 0x7FFFFFFF, 0x7FFFFFFE },
+        [_]u32{ 0xFFFFFFFD, 0x80000000, 0x7FFFFFFD },
+        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFD, 0x00000000 },
+        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFE, 0xFFFFFFFD },
+        [_]u32{ 0xFFFFFFFD, 0xFFFFFFFF, 0xFFFFFFFD },
+        [_]u32{ 0xFFFFFFFE, 0x00000001, 0x00000000 },
+        [_]u32{ 0xFFFFFFFE, 0x00000002, 0x00000000 },
+        [_]u32{ 0xFFFFFFFE, 0x00000003, 0x00000002 },
+        [_]u32{ 0xFFFFFFFE, 0x00000010, 0x0000000E },
+        [_]u32{ 0xFFFFFFFE, 0x078644FA, 0x002AD6CA },
+        [_]u32{ 0xFFFFFFFE, 0x0747AE14, 0x01333342 },
+        [_]u32{ 0xFFFFFFFE, 0x7FFFFFFF, 0x00000000 },
+        [_]u32{ 0xFFFFFFFE, 0x80000000, 0x7FFFFFFE },
+        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFD, 0x00000001 },
+        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFE, 0x00000000 },
+        [_]u32{ 0xFFFFFFFE, 0xFFFFFFFF, 0xFFFFFFFE },
+        [_]u32{ 0xFFFFFFFF, 0x00000001, 0x00000000 },
+        [_]u32{ 0xFFFFFFFF, 0x00000002, 0x00000001 },
+        [_]u32{ 0xFFFFFFFF, 0x00000003, 0x00000000 },
+        [_]u32{ 0xFFFFFFFF, 0x00000010, 0x0000000F },
+        [_]u32{ 0xFFFFFFFF, 0x078644FA, 0x002AD6CB },
+        [_]u32{ 0xFFFFFFFF, 0x0747AE14, 0x01333343 },
+        [_]u32{ 0xFFFFFFFF, 0x7FFFFFFF, 0x00000001 },
+        [_]u32{ 0xFFFFFFFF, 0x80000000, 0x7FFFFFFF },
+        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFD, 0x00000002 },
+        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFE, 0x00000001 },
+        [_]u32{ 0xFFFFFFFF, 0xFFFFFFFF, 0x00000000 },
+    };
+
+    for (cases) |case| {
+        test_one_umodsi3(case[0], case[1], case[2]);
+    }
+}
+
+fn test_one_umodsi3(a: u32, b: u32, expected_r: u32) void {
+    const r: u32 = __umodsi3(a, b);
+    testing.expect(r == expected_r);
+}
diff --git a/lib/std/special/compiler_rt/udivmoddi4.zig b/lib/std/special/compiler_rt/udivmoddi4.zig
deleted file mode 100644
index 79f0f39986..0000000000
--- a/lib/std/special/compiler_rt/udivmoddi4.zig
+++ /dev/null
@@ -1,11 +0,0 @@
-const udivmod = @import("udivmod.zig").udivmod;
-const builtin = @import("builtin");
-
-pub fn __udivmoddi4(a: u64, b: u64, maybe_rem: ?*u64) callconv(.C) u64 {
-    @setRuntimeSafety(builtin.is_test);
-    return udivmod(u64, a, b, maybe_rem);
-}
-
-test "import udivmoddi4" {
-    _ = @import("udivmoddi4_test.zig");
-}
diff --git a/lib/std/special/compiler_rt/udivmoddi4_test.zig b/lib/std/special/compiler_rt/udivmoddi4_test.zig
index 17581fc569..48a38faa04 100644
--- a/lib/std/special/compiler_rt/udivmoddi4_test.zig
+++ b/lib/std/special/compiler_rt/udivmoddi4_test.zig
@@ -1,6 +1,6 @@
 // Disable formatting to avoid unnecessary source repository bloat.
 // zig fmt: off
-const __udivmoddi4 = @import("udivmoddi4.zig").__udivmoddi4;
+const __udivmoddi4 = @import("int.zig").__udivmoddi4;
 const testing = @import("std").testing;
 
 fn test__udivmoddi4(a: u64, b: u64, expected_q: u64, expected_r: u64) void {