[llvm-branch-commits] [llvm] AArch64: Relax x16/x17 constraint on AUT in certain cases. (PR #132857)

[Anatoly Trosinenko via llvm-branch-commits]

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@@ -33,36 +33,45 @@ target datalayout = "e-m:o-i64:64-i128:128-n32:64-S128"
 
 define i64 @test_auth_blend(i64 %arg, i64 %arg1) {
 ; UNCHECKED-LABEL: test_auth_blend:
-; UNCHECKED:       %bb.0:
-; UNCHECKED-NEXT:    mov x16, x0
-; UNCHECKED-NEXT:    mov x17, x1
-; UNCHECKED-NEXT:    movk x17, #65535, lsl #48
-; UNCHECKED-NEXT:    autda x16, x17
-; UNCHECKED-NEXT:    mov x0, x16
-; UNCHECKED-NEXT:    ret
+; UNCHECKED:          %bb.0:
+; UNCHECKED-DARWIN-NEXT: mov x16, x0
+; UNCHECKED-DARWIN-NEXT: mov x17, x1
+; UNCHECKED-DARWIN-NEXT: movk x17, #65535, lsl #48
+; UNCHECKED-DARWIN-NEXT: autda x16, x17
+; UNCHECKED-DARWIN-NEXT: mov x0, x16
+; UNCHECKED-ELF-NEXT:    movk x1, #65535, lsl #48
+; UNCHECKED-ELF-NEXT:    autda x0, x1
+; UNCHECKED-NEXT:        ret
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atrosinenko wrote:

It is worth testing the case of `AUTAddrDisc->isKill()` being false, so that address discriminator is actually copied to a scratch register first and then passed to `movk`.

https://github.com/llvm/llvm-project/pull/132857