27 lines
873 B
LLVM
27 lines
873 B
LLVM
; RUN: llc < %s -march=x86 -mtriple=i386-apple-darwin | FileCheck %s
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; PR8297
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;
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; On i386, i64 cmpxchg is lowered during legalize types to extract the
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; 64-bit result into a pair of fixed regs. So creation of the DAG node
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; happens in a different place. See
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; X86TargetLowering::ReplaceNodeResults, case ATOMIC_CMP_SWAP.
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;
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; Neither Atomic-xx.ll nor atomic_op.ll cover this. Those tests were
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; autogenerated from C source before 64-bit variants were supported.
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;
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; Note that this case requires a loop around the cmpxchg to force
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; machine licm to query alias anlysis, exposing a bad
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; MachineMemOperand.
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define void @foo(i64* %ptr) nounwind inlinehint {
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entry:
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br label %loop
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loop:
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; CHECK: lock
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; CHECK-NEXT: cmpxchg8b
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%r = cmpxchg i64* %ptr, i64 0, i64 1 monotonic
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%stored1 = icmp eq i64 %r, 0
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br i1 %stored1, label %loop, label %continue
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continue:
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ret void
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}
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