[llvm] [X86] Break false dependencies on Zen 4 and 5 (#206849) (PR #207079)

[Simon Pilgrim via llvm-commits]

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@@ -0,0 +1,448 @@
+; RUN: llc -verify-machineinstrs -mcpu=x86-64-v3 -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=x86-64-v3 -mattr=+false-deps-bls -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=SLOW,ALL
+; RUN: llc -verify-machineinstrs -mcpu=haswell -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=skylake -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=skx -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=icelake-client -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=alderlake -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=sapphirerapids -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=emeraldrapids -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=graniterapids -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=znver4 -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+; RUN: llc -verify-machineinstrs -mcpu=znver5 -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=SLOW,ALL
+; RUN: llc -verify-machineinstrs -mcpu=znver6 -mtriple=x86_64-unknown-unknown < %s | FileCheck %s --check-prefixes=FAST,ALL
+
+
+; Test that dependencies on the output register are broken if it was written recently (write simulated using inline asm).
+
+
+define i32 @blsi32_rr(i32 %a0) {
+; SLOW-LABEL: blsi32_rr:
+; SLOW:       # %bb.0:
+; SLOW-NEXT:    #APP
+; SLOW-NEXT:    #NO_APP
+; SLOW-NEXT:    xorl %eax, %eax
+; SLOW-NEXT:    blsil %edi, %eax
+; SLOW-NEXT:    retq
+;
+; FAST-LABEL: blsi32_rr:
+; FAST:       # %bb.0:
+; FAST-NEXT:    #APP
+; FAST-NEXT:    #NO_APP
+; FAST-NEXT:    blsil %edi, %eax
+; FAST-NEXT:    retq
+  %1 = tail call <2 x i64> asm sideeffect "", "=x,~{eax}"()
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RKSimon wrote:

cheers - yes replacing the BMI ll tests with MIR tests in a future PR would be better

https://github.com/llvm/llvm-project/pull/207079