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; RUN: llc -mcpu=core-avx2 -mtriple=x86_64 -o - %s | FileCheck %s
define i1 @try_cmpxchg(i128* %addr, i128 %desired, i128 %new) {
; CHECK-LABEL: try_cmpxchg:
; CHECK: cmpxchg16b
; CHECK-NOT: cmp
; CHECK: sete %al
; CHECK: retq
%pair = cmpxchg i128* %addr, i128 %desired, i128 %new seq_cst seq_cst
%success = extractvalue { i128, i1 } %pair, 1
ret i1 %success
}
define void @cmpxchg_flow(i128* %addr, i128 %desired, i128 %new) {
; CHECK-LABEL: cmpxchg_flow:
; CHECK: cmpxchg16b
; CHECK-NOT: cmp
; CHECK-NOT: set
; CHECK: {{jne|jeq}}
%pair = cmpxchg i128* %addr, i128 %desired, i128 %new seq_cst seq_cst
%success = extractvalue { i128, i1 } %pair, 1
br i1 %success, label %true, label %false
true:
call void @foo()
ret void
false:
call void @bar()
ret void
}
; Can't use the flags here because cmpxchg16b only sets ZF.
define i1 @cmpxchg_arithcmp(i128* %addr, i128 %desired, i128 %new) {
; CHECK-LABEL: cmpxchg_arithcmp:
; CHECK: cmpxchg16b
; CHECK: cmpq
; CHECK: retq
%pair = cmpxchg i128* %addr, i128 %desired, i128 %new seq_cst seq_cst
%oldval = extractvalue { i128, i1 } %pair, 0
%success = icmp sge i128 %oldval, %desired
ret i1 %success
}
define i128 @cmpxchg_zext(i128* %addr, i128 %desired, i128 %new) {
; CHECK-LABEL: cmpxchg_zext:
; CHECK: cmpxchg16b
; CHECK-NOT: cmpq
; CHECK: sete [[BYTE:%[a-z0-9]+]]
; CHECK: movzbl [[BYTE]], %eax
%pair = cmpxchg i128* %addr, i128 %desired, i128 %new seq_cst seq_cst
%success = extractvalue { i128, i1 } %pair, 1
%mask = zext i1 %success to i128
ret i128 %mask
}
define i128 @cmpxchg_use_eflags_and_val(i128* %addr, i128 %offset) {
; CHECK-LABEL: cmpxchg_use_eflags_and_val:
; CHECK: cmpxchg16b
; CHECK-NOT: cmpq
; CHECK: jne
entry:
%init = load atomic i128, i128* %addr seq_cst, align 16
br label %loop
loop:
%old = phi i128 [%init, %entry], [%oldval, %loop]
%new = add i128 %old, %offset
%pair = cmpxchg i128* %addr, i128 %old, i128 %new seq_cst seq_cst
%oldval = extractvalue { i128, i1 } %pair, 0
%success = extractvalue { i128, i1 } %pair, 1
br i1 %success, label %done, label %loop
done:
ret i128 %old
}
declare void @foo()
declare void @bar()
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