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[X86] Fix
(shift X, (xor Y, N-1))
-> (shift X, (not Y))
by proper…
…ly inserting `not Y` into DAG. [#61038] Previously not inserting the `-1` in `not Y` (`xor Y, -1`) into the DAG. Not inserting `-1` as a DAG node comes up as a bug when doing `(xor (shl 1, A), B)` -> `(btc A, B)`. `btc` requires `B` (dst) to be a register. Differential Revision: https://reviews.llvm.org/D144984 (cherry picked from commit 4a23031)
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; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py | ||
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=skylake-avx512 | FileCheck %s --check-prefix=CHECK-BMI2 | ||
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mcpu=x86-64-v4 | FileCheck %s --check-prefix=CHECK-BMI2 | ||
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=+bmi | FileCheck %s --check-prefix=CHECK-BMI | ||
|
||
declare i32 @llvm.cttz.i32(i32, i1 immarg) | ||
define void @test_61038(ptr %tmp_buffer) { | ||
; CHECK-BMI2-LABEL: test_61038: | ||
; CHECK-BMI2: # %bb.0: # %entry | ||
; CHECK-BMI2-NEXT: tzcntl %eax, %eax | ||
; CHECK-BMI2-NEXT: movabsq $8589934591, %rcx # imm = 0x1FFFFFFFF | ||
; CHECK-BMI2-NEXT: movq $-1, %rdx | ||
; CHECK-BMI2-NEXT: btcq %rax, %rdx | ||
; CHECK-BMI2-NEXT: shrxq %rdx, %rcx, %rdx | ||
; CHECK-BMI2-NEXT: btcq %rax, %rcx | ||
; CHECK-BMI2-NEXT: xorl %eax, %eax | ||
; CHECK-BMI2-NEXT: cmpq $64, %rcx | ||
; CHECK-BMI2-NEXT: cmovael %eax, %edx | ||
; CHECK-BMI2-NEXT: movl %edx, (%rdi) | ||
; CHECK-BMI2-NEXT: retq | ||
; | ||
; CHECK-BMI-LABEL: test_61038: | ||
; CHECK-BMI: # %bb.0: # %entry | ||
; CHECK-BMI-NEXT: tzcntl %eax, %eax | ||
; CHECK-BMI-NEXT: movabsq $8589934591, %rdx # imm = 0x1FFFFFFFF | ||
; CHECK-BMI-NEXT: movq %rdx, %rsi | ||
; CHECK-BMI-NEXT: btcq %rax, %rsi | ||
; CHECK-BMI-NEXT: movq $-1, %rcx | ||
; CHECK-BMI-NEXT: btcq %rax, %rcx | ||
; CHECK-BMI-NEXT: # kill: def $cl killed $cl killed $rcx | ||
; CHECK-BMI-NEXT: shrq %cl, %rdx | ||
; CHECK-BMI-NEXT: xorl %eax, %eax | ||
; CHECK-BMI-NEXT: cmpq $64, %rsi | ||
; CHECK-BMI-NEXT: cmovael %eax, %edx | ||
; CHECK-BMI-NEXT: movl %edx, (%rdi) | ||
; CHECK-BMI-NEXT: retq | ||
entry: | ||
%0 = tail call i32 @llvm.cttz.i32(i32 poison, i1 false) | ||
%1 = zext i32 %0 to i64 | ||
%2 = shl nuw nsw i64 1, %1 | ||
%3 = xor i64 %2, 8589934591 | ||
%4 = icmp ugt i64 %3, 63 | ||
%x11.op.i = lshr i64 8589934591, %3 | ||
%5 = trunc i64 %x11.op.i to i32 | ||
%6 = select i1 %4, i32 0, i32 %5 | ||
store i32 %6, ptr %tmp_buffer, align 4 | ||
ret void | ||
} |