stage2: more division support

AIR:
 * div is renamed to div_trunc.
 * Add div_float, div_floor, div_exact.
   - Implemented in Sema and LLVM codegen. C backend has a stub.

Improvements to std.math.big.Int:
 * Add `eqZero` function to `Mutable`.
 * Fix incorrect results for `divFloor`.

Compiler-rt:
 * Add muloti4 to the stage2 section.

1 files changed, 52 insertions, 0 deletions

diff --git a/test/behavior/array.zig b/test/behavior/array.zig
index 0b4babca67..3ff339b140 100644
--- a/test/behavior/array.zig
+++ b/test/behavior/array.zig
@@ -112,3 +112,55 @@ test "void arrays" {
     try expect(@sizeOf(@TypeOf(array)) == 0);
     try expect(array.len == 4);
 }
+
+test "nested arrays" {
+    const array_of_strings = [_][]const u8{ "hello", "this", "is", "my", "thing" };
+    for (array_of_strings) |s, i| {
+        if (i == 0) try expect(mem.eql(u8, s, "hello"));
+        if (i == 1) try expect(mem.eql(u8, s, "this"));
+        if (i == 2) try expect(mem.eql(u8, s, "is"));
+        if (i == 3) try expect(mem.eql(u8, s, "my"));
+        if (i == 4) try expect(mem.eql(u8, s, "thing"));
+    }
+}
+
+var s_array: [8]Sub = undefined;
+const Sub = struct { b: u8 };
+const Str = struct { a: []Sub };
+test "set global var array via slice embedded in struct" {
+    var s = Str{ .a = s_array[0..] };
+
+    s.a[0].b = 1;
+    s.a[1].b = 2;
+    s.a[2].b = 3;
+
+    try expect(s_array[0].b == 1);
+    try expect(s_array[1].b == 2);
+    try expect(s_array[2].b == 3);
+}
+
+test "implicit comptime in array type size" {
+    var arr: [plusOne(10)]bool = undefined;
+    try expect(arr.len == 11);
+}
+
+fn plusOne(x: u32) u32 {
+    return x + 1;
+}
+
+test "read/write through global variable array of struct fields initialized via array mult" {
+    const S = struct {
+        fn doTheTest() !void {
+            try expect(storage[0].term == 1);
+            storage[0] = MyStruct{ .term = 123 };
+            try expect(storage[0].term == 123);
+        }
+
+        pub const MyStruct = struct {
+            term: usize,
+        };
+
+        var storage: [1]MyStruct = [_]MyStruct{MyStruct{ .term = 1 }} ** 1;
+    };
+    try S.doTheTest();
+}