llvm-6502/test/CodeGen/X86/cas.ll
Eric Christopher a9bd4b4647 Check and allow floating point registers to select the size of the
register for inline asm. This conforms to how gcc allows for effective
casting of inputs into gprs (fprs is already handled).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174008 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31 00:50:46 +00:00

43 lines
1.6 KiB
LLVM

; 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