[llvm] [InitUndef] Enable the InitUndef pass on AArch64 (PR #108353)

[Eli Friedman via llvm-commits]

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@@ -354,11 +354,10 @@ define dso_local i32 @test_store_release_i64(i32, i64 %val, ptr %addr) {
 }
 
 ; The stxp result cannot be allocated to the same register as the inputs.
-; FIXME: This is a miscompile.
 define dso_local i32 @test_stxp_undef(ptr %p, i64 %x) nounwind {
 ; CHECK-LABEL: test_stxp_undef:
 ; CHECK:       // %bb.0:
-; CHECK-NEXT:    stxp w8, x8, x1, [x0]
+; CHECK-NEXT:    stxp w8, x9, x1, [x0]
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efriedma-quic wrote:

AArch64InstrInfo::verifyInstruction is the place for target-specific verification of an instruction... but currently it only gets called with -verify-machineinstrs.  (It looks like AMDGPUAsmPrinter::emitInstruction calls verifyInstruction, but other targets currently don't do that.)

https://github.com/llvm/llvm-project/pull/108353