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; RUN: llc -mtriple=x86_64-pc-linux-gnu %s -o - | FileCheck %s
; C code this came from
;bool cas(float volatile *p, float *expected, float desired) {
; bool success;
; __asm__ __volatile__("lock; cmpxchg %[desired], %[mem]; "
; "mov %[expected], %[expected_out]; "
; "sete %[success]"
; : [success] "=a" (success),
; [expected_out] "=rm" (*expected)
; : [expected] "a" (*expected),
; [desired] "q" (desired),
; [mem] "m" (*p)
; : "memory", "cc");
; return success;
;}
define zeroext i1 @cas(float* %p, float* %expected, float %desired) nounwind {
entry:
%p.addr = alloca float*, align 8
%expected.addr = alloca float*, align 8
%desired.addr = alloca float, align 4
%success = alloca i8, align 1
store float* %p, float** %p.addr, align 8
store float* %expected, float** %expected.addr, align 8
store float %desired, float* %desired.addr, align 4
%0 = load float** %expected.addr, align 8
%1 = load float** %expected.addr, align 8
%2 = load float* %1, align 4
%3 = load float* %desired.addr, align 4
%4 = load float** %p.addr, align 8
%5 = call i8 asm sideeffect "lock; cmpxchg $3, $4; mov $2, $1; sete $0", "={ax},=*rm,{ax},q,*m,~{memory},~{cc},~{dirflag},~{fpsr},~{flags}"(float* %0, float %2, float %3, float* %4) nounwind
store i8 %5, i8* %success, align 1
%6 = load i8* %success, align 1
%tobool = trunc i8 %6 to i1
ret i1 %tobool
}
; Make sure we're emitting a move from
; CHECK: #APP
; CHECK-NEXT: lock;{{.*}}mov %eax,{{.*}}
; CHECK-NEXT: #NO_APP
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