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Diffstat (limited to 'test/CodeGen/X86/2010-10-08-cmpxchg8b.ll')
-rw-r--r-- | test/CodeGen/X86/2010-10-08-cmpxchg8b.ll | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/test/CodeGen/X86/2010-10-08-cmpxchg8b.ll b/test/CodeGen/X86/2010-10-08-cmpxchg8b.ll new file mode 100644 index 0000000..0fd4a34 --- /dev/null +++ b/test/CodeGen/X86/2010-10-08-cmpxchg8b.ll @@ -0,0 +1,28 @@ +; RUN: llc < %s -march=x86 -mtriple=i386-apple-darwin | FileCheck %s +; bug 8297 +; +; On i386, i64 cmpxchg is lowered during legalize types to extract the +; 64-bit result into a pair of fixed regs. So creation of the DAG node +; happens in a different place. See +; X86TargetLowering::ReplaceNodeResults, case ATOMIC_CMP_SWAP. +; +; Neither Atomic-xx.ll nor atomic_op.ll cover this. Those tests were +; autogenerated from C source before 64-bit variants were supported. +; +; Note that this case requires a loop around the cmpxchg to force +; machine licm to query alias anlysis, exposing a bad +; MachineMemOperand. +define void @foo(i64* %ptr) nounwind inlinehint { +entry: + br label %loop +loop: +; CHECK: lock +; CHECK-NEXT: cmpxchg8b + %r = call i64 @llvm.atomic.cmp.swap.i64.p0i64(i64* %ptr, i64 0, i64 1) + %stored1 = icmp eq i64 %r, 0 + br i1 %stored1, label %loop, label %continue +continue: + ret void +} + +declare i64 @llvm.atomic.cmp.swap.i64.p0i64(i64* nocapture, i64, i64) nounwind |