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; RUN: llc < %s -mtriple=aarch64-linux-gnu | FileCheck %s
; Test function which compares two integers and returns the value of
; the overflow flag, by using an asm goto to make the asm block branch
; based on that flag, and then a phi to set the return value based on
; whether the branch was taken.
define i32 @overflow(i64 %a, i64 %b) #0 {
asm:
callbr void asm sideeffect "cmp $0, $1 \0A\09 b.vs ${2:l}",
"r,r,!i,~{cc}"(i64 %a, i64 %b)
to label %fallthrough [label %indirect]
indirect:
br label %fallthrough
fallthrough:
; Return 1 if we came via the 'indirect' block (because the b.vs was
; taken), and 0 if we came straight from the asm block (because it
; was untaken).
%retval = phi i32 [0, %asm], [1, %indirect]
ret i32 %retval
}
; CHECK: overflow:
; CHECK-NEXT: .cfi_startproc
; CHECK-NEXT: // %bb.{{[0-9]+}}:
; CHECK-NEXT: bti c
; CHECK-NEXT: //APP
; CHECK-NEXT: cmp x0, x1
; CHECK-NEXT: b.vs [[LABEL:\.[A-Za-z0-9_]+]]
; CHECK-NEXT: //NO_APP
; CHECK-NEXT: // %bb.{{[0-9]+}}:
; CHECK-NEXT: mov w0, wzr
; CHECK-NEXT: ret
; CHECK-NEXT: [[LABEL]]:
; CHECK-NOT: bti
; CHECK: mov w0, #1
; CHECK-NEXT: ret
attributes #0 = { "branch-target-enforcement" "target-features"="+bti" }
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