1 files changed, 85 insertions, 0 deletions
diff --git a/lib/std/special/compiler_rt/addXf3_test.zig b/lib/std/special/compiler_rt/addXf3_test.zig
new file mode 100644
index 0000000000..099b737976
--- /dev/null
+++ b/lib/std/special/compiler_rt/addXf3_test.zig
@@ -0,0 +1,85 @@
+// Ported from:
+//
+// https://github.com/llvm/llvm-project/blob/02d85149a05cb1f6dc49f0ba7a2ceca53718ae17/compiler-rt/test/builtins/Unit/addtf3_test.c
+// https://github.com/llvm/llvm-project/blob/02d85149a05cb1f6dc49f0ba7a2ceca53718ae17/compiler-rt/test/builtins/Unit/subtf3_test.c
+
+const qnan128 = @bitCast(f128, u128(0x7fff800000000000) << 64);
+const inf128 = @bitCast(f128, u128(0x7fff000000000000) << 64);
+
+const __addtf3 = @import("addXf3.zig").__addtf3;
+
+fn test__addtf3(a: f128, b: f128, expected_hi: u64, expected_lo: u64) void {
+    const x = __addtf3(a, b);
+
+    const rep = @bitCast(u128, x);
+    const hi = @intCast(u64, rep >> 64);
+    const lo = @truncate(u64, rep);
+
+    if (hi == expected_hi and lo == expected_lo) {
+        return;
+    }
+    // test other possible NaN representation (signal NaN)
+    else if (expected_hi == 0x7fff800000000000 and expected_lo == 0x0) {
+        if ((hi & 0x7fff000000000000) == 0x7fff000000000000 and
+            ((hi & 0xffffffffffff) > 0 or lo > 0))
+        {
+            return;
+        }
+    }
+
+    @panic("__addtf3 test failure");
+}
+
+test "addtf3" {
+    test__addtf3(qnan128, 0x1.23456789abcdefp+5, 0x7fff800000000000, 0x0);
+
+    // NaN + any = NaN
+    test__addtf3(@bitCast(f128, (u128(0x7fff000000000000) << 64) | u128(0x800030000000)), 0x1.23456789abcdefp+5, 0x7fff800000000000, 0x0);
+
+    // inf + inf = inf
+    test__addtf3(inf128, inf128, 0x7fff000000000000, 0x0);
+
+    // inf + any = inf
+    test__addtf3(inf128, 0x1.2335653452436234723489432abcdefp+5, 0x7fff000000000000, 0x0);
+
+    // any + any
+    test__addtf3(0x1.23456734245345543849abcdefp+5, 0x1.edcba52449872455634654321fp-1, 0x40042afc95c8b579, 0x61e58dd6c51eb77c);
+}
+
+const __subtf3 = @import("addXf3.zig").__subtf3;
+
+fn test__subtf3(a: f128, b: f128, expected_hi: u64, expected_lo: u64) void {
+    const x = __subtf3(a, b);
+
+    const rep = @bitCast(u128, x);
+    const hi = @intCast(u64, rep >> 64);
+    const lo = @truncate(u64, rep);
+
+    if (hi == expected_hi and lo == expected_lo) {
+        return;
+    }
+    // test other possible NaN representation (signal NaN)
+    else if (expected_hi == 0x7fff800000000000 and expected_lo == 0x0) {
+        if ((hi & 0x7fff000000000000) == 0x7fff000000000000 and
+            ((hi & 0xffffffffffff) > 0 or lo > 0))
+        {
+            return;
+        }
+    }
+
+    @panic("__subtf3 test failure");
+}
+
+test "subtf3" {
+    // qNaN - any = qNaN
+    test__subtf3(qnan128, 0x1.23456789abcdefp+5, 0x7fff800000000000, 0x0);
+
+    // NaN + any = NaN
+    test__subtf3(@bitCast(f128, (u128(0x7fff000000000000) << 64) | u128(0x800030000000)), 0x1.23456789abcdefp+5, 0x7fff800000000000, 0x0);
+
+    // inf - any = inf
+    test__subtf3(inf128, 0x1.23456789abcdefp+5, 0x7fff000000000000, 0x0);
+
+    // any + any
+    test__subtf3(0x1.234567829a3bcdef5678ade36734p+5, 0x1.ee9d7c52354a6936ab8d7654321fp-1, 0x40041b8af1915166, 0xa44a7bca780a166c);
+}