stage2: register allocator processes operand deaths

also rework the IR data structures

1 files changed, 37 insertions, 0 deletions

diff --git a/test/stage2/compare_output.zig b/test/stage2/compare_output.zig
index 6a6772f935..d013573e30 100644
--- a/test/stage2/compare_output.zig
+++ b/test/stage2/compare_output.zig
@@ -267,5 +267,42 @@ pub fn addCases(ctx: *TestContext) !void {
         ,
             "",
         );
+
+        // Requires a second move. The register allocator should figure out to re-use rax.
+        case.addCompareOutput(
+            \\export fn _start() noreturn {
+            \\    add(3, 4);
+            \\
+            \\    exit();
+            \\}
+            \\
+            \\fn add(a: u32, b: u32) void {
+            \\    const c = a + b; // 7
+            \\    const d = a + c; // 10
+            \\    const e = d + b; // 14
+            \\    const f = d + e; // 24
+            \\    const g = e + f; // 38
+            \\    const h = f + g; // 62
+            \\    const i = g + h; // 100
+            \\    const j = i + d; // 110
+            \\    assert(j == 110);
+            \\}
+            \\
+            \\pub fn assert(ok: bool) void {
+            \\    if (!ok) unreachable; // assertion failure
+            \\}
+            \\
+            \\fn exit() noreturn {
+            \\    asm volatile ("syscall"
+            \\        :
+            \\        : [number] "{rax}" (231),
+            \\          [arg1] "{rdi}" (0)
+            \\        : "rcx", "r11", "memory"
+            \\    );
+            \\    unreachable;
+            \\}
+        ,
+            "",
+        );
     }
 }