[llvm] [X86] Sink NOT to be fold into ANDN (PR #172329)

[Piotr Fusik via llvm-commits]

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@@ -0,0 +1,3168 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -mtriple=i686-- -mattr=-bmi | FileCheck %s --check-prefixes=X86-NOBMI,X86
+; RUN: llc < %s -mtriple=i686-- -mattr=-bmi,+sse | FileCheck %s --check-prefixes=X86-NOBMI,X86-SSE
+; RUN: llc < %s -mtriple=i686-- -mattr=-bmi,+sse2 | FileCheck %s --check-prefixes=X86-NOBMI,X86-SSE2
+; RUN: llc < %s -mtriple=i686-- -mattr=+bmi | FileCheck %s --check-prefixes=X86-BMI
+; RUN: llc < %s -mtriple=x86_64-- -mattr=-bmi | FileCheck %s --check-prefixes=X64,X64-NOAVX2,X64-NOBMI
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+bmi | FileCheck %s --check-prefixes=X64,X64-BMI,X64-NOAVX2
+; RUN: llc < %s -mtriple=x86_64-- -mattr=+bmi,+avx2 | FileCheck %s --check-prefixes=X64,X64-BMI,X64-AVX2
+
+define i8 @and_sink_not_i8(i8 %x, i8 %m, i1 zeroext %cond) {
+; X86-NOBMI-LABEL: and_sink_not_i8:
+; X86-NOBMI:       # %bb.0:
+; X86-NOBMI-NEXT:    movzbl {{[0-9]+}}(%esp), %eax
+; X86-NOBMI-NEXT:    cmpb $0, {{[0-9]+}}(%esp)
+; X86-NOBMI-NEXT:    je .LBB0_2
+; X86-NOBMI-NEXT:  # %bb.1: # %mask
+; X86-NOBMI-NEXT:    movzbl {{[0-9]+}}(%esp), %ecx
+; X86-NOBMI-NEXT:    notb %cl
+; X86-NOBMI-NEXT:    andb %al, %cl
+; X86-NOBMI-NEXT:    movl %ecx, %eax
+; X86-NOBMI-NEXT:  .LBB0_2: # %identity
+; X86-NOBMI-NEXT:    retl
+;
+; X86-BMI-LABEL: and_sink_not_i8:
+; X86-BMI:       # %bb.0:
+; X86-BMI-NEXT:    movzbl {{[0-9]+}}(%esp), %eax
+; X86-BMI-NEXT:    cmpb $0, {{[0-9]+}}(%esp)
+; X86-BMI-NEXT:    je .LBB0_2
+; X86-BMI-NEXT:  # %bb.1: # %mask
+; X86-BMI-NEXT:    movzbl {{[0-9]+}}(%esp), %ecx
+; X86-BMI-NEXT:    notb %cl
+; X86-BMI-NEXT:    andb %al, %cl
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pfusik wrote:

I don't know why `andn` is not used for `i8`.

https://github.com/llvm/llvm-project/pull/172329