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1; RUN: llc < %s -mtriple=s390x-linux-gnu | FileCheck %s2 3; Check that the stackmap shadow optimization is only outputting a 2-byte4; nop here. 8-bytes are requested, but 6 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: brasl %r14, bar@PLT15; CHECK-NEXT: .Ltmp16; CHECK-NEXT: bcr 0, %r017; CHECK-NEXT: brasl %r14, bar@PLT18; CHECK-NEXT: brasl %r14, bar@PLT19 call void @bar()20 tail call void (i64, i32, ...) @llvm.experimental.stackmap(i64 0, i32 8)21 call void @bar()22 call void @bar()23 ret void24}25declare void @bar()26 27declare void @llvm.experimental.stackmap(i64, i32, ...)28