Files
clang-p2996/llvm/test/CodeGen/AArch64/patchable-function-entry-bti.ll
Daniel Kiss 1782810b84 [Clang][ARM][AArch64] Alway emit protection attributes for functions. (#82819)
So far branch protection, sign return address, guarded control stack
attributes are
only emitted as module flags to indicate the functions need to be
generated with
those features.
The problem is in case of an LTO build the module flags are merged with
the `min`
rule which means if one of the module is not build with sign return
address then the features
will be turned off for all functions. Due to the functions take the
branch-protection and
sign-return-address features from the module flags. The
sign-return-address is
function level option therefore it is expected functions from files that
is
compiled with -mbranch-protection=pac-ret to be protected.
The inliner might inline functions with different set of flags as it
doesn't consider
the module flags.

This patch adds the attributes to all functions and drops the checking
of the module flags
for the code generation.
Module flag is still used for generating the ELF markers.
Also drops the "true"/"false" values from the
branch-protection-enforcement,
branch-protection-pauth-lr, guarded-control-stack attributes as presence
of the
attribute means it is on absence means off and no other option.

Releand with test fixes.
2024-07-10 11:32:41 +02:00

107 lines
3.1 KiB
LLVM

; RUN: llc -mtriple=aarch64 -aarch64-min-jump-table-entries=4 %s -o - | FileCheck %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{{$}}
; CHECK-NEXT: .p2align 3
; CHECK-NEXT: .xword .Lpatch0
ret void
}
;; -fpatchable-function-entry=2,1 -mbranch-protection=bti
define void @f2_1() "patchable-function-entry"="1" "patchable-function-prefix"="1" "branch-target-enforcement" {
; CHECK-LABEL: .type f2_1,@function
; CHECK-NEXT: .Ltmp0:
; CHECK-NEXT: nop
; CHECK-NEXT: f2_1:
; CHECK-NEXT: .Lfunc_begin2:
; CHECK-NEXT: .cfi_startproc
; CHECK-NEXT: // %bb.0:
; CHECK-NEXT: hint #34
; CHECK-NEXT: nop
; CHECK-NEXT: ret
; CHECK: .Lfunc_end2:
; CHECK-NEXT: .size f2_1, .Lfunc_end2-f2_1
; CHECK: .section __patchable_function_entries,"awo",@progbits,f2_1{{$}}
; CHECK-NEXT: .p2align 3
; CHECK-NEXT: .xword .Ltmp0
ret void
}
;; -fpatchable-function-entry=1 -mbranch-protection=bti
;; We add BTI c even when the function has internal linkage
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: hint #34
; CHECK-NEXT: .Lpatch1:
; 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,f1i{{$}}
; CHECK-NEXT: .p2align 3
; CHECK-NEXT: .xword .Lpatch1
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 "nop", ""()
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
}
;; Test the interaction with -fsanitize=function.
; CHECK: .type sanitize_function,@function
; CHECK-NEXT: .Ltmp{{.*}}:
; CHECK-NEXT: nop
; CHECK-NEXT: .word 3238382334 // 0xc105cafe
; CHECK-NEXT: .word 42
; CHECK-NEXT: sanitize_function:
; CHECK-NEXT: .Lfunc_begin{{.*}}:
; CHECK-NEXT: .cfi_startproc
; CHECK-NEXT: // %bb.0:
; CHECK-NEXT: hint #34
; CHECK-NEXT: nop
; CHECK-NEXT: ret
define void @sanitize_function(ptr noundef %x) "patchable-function-prefix"="1" "patchable-function-entry"="1" "branch-target-enforcement" !func_sanitize !0 {
ret void
}
!0 = !{i32 3238382334, i32 42}