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1; RUN: llc < %s -mtriple=x86_64-apple-darwin -mcpu=corei7 | FileCheck %s2 3; Check that the X86 stackmap shadow optimization is only outputting a 3-byte4; nop here. 8-bytes are requested, but 5 are covered by the code for the call to5; bar. However, the frame teardown and the return do not count towards the6; stackmap shadow as the call return counts as a branch target so must flush7; the shadow.8; Note that in order for a thread to not return in to the patched space9; the call must be at the end of the shadow, so the required nop must be10; before the call, not after.11define void @shadow_optimization_test() {12entry:13; CHECK-LABEL: shadow_optimization_test:14; CHECK: callq _bar15; CHECK: nop16; CHECK: callq _bar17; CHECK-NOT: nop18; CHECK: callq _bar19; CHECK-NOT: nop20 call void @bar()21 tail call void (i64, i32, ...) @llvm.experimental.stackmap(i64 0, i32 8)22 call void @bar()23 call void @bar()24 ret void25}26 27declare void @llvm.experimental.stackmap(i64, i32, ...)28declare void @bar()29