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Diffstat (limited to 'test/CodeGen/X86/stackmap-shadow-optimization.ll')
| -rw-r--r-- | test/CodeGen/X86/stackmap-shadow-optimization.ll | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/test/CodeGen/X86/stackmap-shadow-optimization.ll b/test/CodeGen/X86/stackmap-shadow-optimization.ll new file mode 100644 index 000000000000..a3725f2c5b72 --- /dev/null +++ b/test/CodeGen/X86/stackmap-shadow-optimization.ll @@ -0,0 +1,28 @@ +; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=corei7 | FileCheck %s + +; Check that the X86 stackmap shadow optimization is only outputting a 3-byte +; nop here. 8-bytes are requested, but 5 are covered by the code for the call to +; bar. However, the frame teardown and the return do not count towards the +; stackmap shadow as the call return counts as a branch target so must flush +; the shadow. +; Note that in order for a thread to not return in to the patched space +; the call must be at the end of the shadow, so the required nop must be +; before the call, not after. +define void @shadow_optimization_test() { +entry: +; CHECK-LABEL: shadow_optimization_test: +; CHECK: callq _bar +; CHECK: nop +; CHECK: callq _bar +; CHECK-NOT: nop +; CHECK: callq _bar +; CHECK-NOT: nop + call void @bar() + tail call void (i64, i32, ...)* @llvm.experimental.stackmap(i64 0, i32 8) + call void @bar() + call void @bar() + ret void +} + +declare void @llvm.experimental.stackmap(i64, i32, ...) +declare void @bar() |