patchable-function-entry-bti.ll
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; RUN: llc -mtriple=aarch64 %s -o - | FileCheck --check-prefixes=CHECK %s
define void @f0() "patchable-function-entry"="0" "branch-target-enforcement" {
; CHECK-LABEL: f0:
; CHECK-NEXT: .Lfunc_begin0:
; CHECK: // %bb.0:
; CHECK-NEXT: hint #34
; CHECK-NEXT: ret
; CHECK-NOT: .section __patchable_function_entries
ret void
}
;; -fpatchable-function-entry=1 -mbranch-protection=bti
;; For M=0, place the label .Lpatch0 after the initial BTI.
define void @f1() "patchable-function-entry"="1" "branch-target-enforcement" {
; CHECK-LABEL: f1:
; CHECK-NEXT: .Lfunc_begin1:
; CHECK-NEXT: .cfi_startproc
; CHECK-NEXT: // %bb.0:
; CHECK-NEXT: hint #34
; CHECK-NEXT: .Lpatch0:
; CHECK-NEXT: nop
; CHECK-NEXT: ret
; CHECK: .section __patchable_function_entries,"awo",@progbits,f1,unique,0
; CHECK-NEXT: .p2align 3
; CHECK-NEXT: .xword .Lpatch0
ret void
}
;; -fpatchable-function-entry=2,1 -mbranch-protection=bti
define void @f2_1() "patchable-function-entry"="1" "patchable-function-prefix"="1" "branch-target-enforcement" {
; CHECK-LABEL: .type f2_1,@function
; CHECK-NEXT: .Ltmp0:
; CHECK-NEXT: nop
; CHECK-NEXT: f2_1:
; CHECK-NEXT: .Lfunc_begin2:
; CHECK-NEXT: .cfi_startproc
; CHECK-NEXT: // %bb.0:
; CHECK-NEXT: hint #34
; CHECK-NEXT: nop
; CHECK-NEXT: ret
; CHECK: .Lfunc_end2:
; CHECK-NEXT: .size f2_1, .Lfunc_end2-f2_1
; CHECK: .section __patchable_function_entries,"awo",@progbits,f1,unique,0
; CHECK-NEXT: .p2align 3
; CHECK-NEXT: .xword .Ltmp0
ret void
}
;; -fpatchable-function-entry=1 -mbranch-protection=bti
;; For M=0, don't create .Lpatch0 if the initial instruction is not BTI,
;; even if other basic blocks may have BTI.
define internal void @f1i(i64 %v) "patchable-function-entry"="1" "branch-target-enforcement" {
; CHECK-LABEL: f1i:
; CHECK-NEXT: .Lfunc_begin3:
; CHECK: // %bb.0:
; CHECK-NEXT: nop
;; Other basic blocks have BTI, but they don't affect our decision to not create .Lpatch0
; CHECK: .LBB{{.+}} // %sw.bb1
; CHECK-NEXT: hint #36
; CHECK: .section __patchable_function_entries,"awo",@progbits,f1,unique,0
; CHECK-NEXT: .p2align 3
; CHECK-NEXT: .xword .Lfunc_begin3
entry:
switch i64 %v, label %sw.bb0 [
i64 1, label %sw.bb1
i64 2, label %sw.bb2
i64 3, label %sw.bb3
i64 4, label %sw.bb4
]
sw.bb0:
call void asm sideeffect "", ""()
ret void
sw.bb1:
call void asm sideeffect "", ""()
ret void
sw.bb2:
call void asm sideeffect "", ""()
ret void
sw.bb3:
call void asm sideeffect "", ""()
ret void
sw.bb4:
call void asm sideeffect "", ""()
ret void
}