llvm/test/CodeGen/X86/mfence.ll
Sanjay Patel 5fb1d32848 [x86-64] allow mfence even with -mno-sse (PR23203)
As shown in:
https://llvm.org/bugs/show_bug.cgi?id=23203
...we currently die because lowering believes that mfence is allowed without SSE2 on x86-64,
but the instruction def doesn't know that.

I don't know if allowing mfence without SSE is right, but if not, at least now it's consistently wrong. :)

Differential Revision: http://reviews.llvm.org/D17219



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@260828 91177308-0d34-0410-b5e6-96231b3b80d8
2016-02-13 17:26:29 +00:00

38 lines
956 B
LLVM

; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
; RUN: llc < %s -mtriple=i386-unknown-unknown -mattr=+sse2 | FileCheck %s --check-prefix=X32
; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=-sse2 | FileCheck %s --check-prefix=X64
; It doesn't matter if an x86-64 target has specified "no-sse2"; we still can use mfence.
define void @test() {
; X32-LABEL: test:
; X32: # BB#0:
; X32-NEXT: mfence
; X32-NEXT: retl
;
; X64-LABEL: test:
; X64: # BB#0:
; X64-NEXT: mfence
; X64-NEXT: retq
fence seq_cst
ret void
}
define i32 @fence(i32* %ptr) {
; X32-LABEL: fence:
; X32: # BB#0:
; X32-NEXT: movl {{[0-9]+}}(%esp), %eax
; X32-NEXT: mfence
; X32-NEXT: movl (%eax), %eax
; X32-NEXT: retl
;
; X64-LABEL: fence:
; X64: # BB#0:
; X64-NEXT: mfence
; X64-NEXT: movl (%rdi), %eax
; X64-NEXT: retq
%atomic = atomicrmw add i32* %ptr, i32 0 seq_cst
ret i32 %atomic
}