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| # RUN: llc -run-pass=aarch64-branch-targets %s -o - | FileCheck %s
--- |
target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
target triple = "aarch64-arm-none-eabi"
define hidden i32 @simple_external() "branch-target-enforcement" {
entry:
ret i32 0
}
define internal i32 @simple_internal() "branch-target-enforcement" {
entry:
ret i32 0
}
define hidden i32 @ptr_auth() "branch-target-enforcement" {
entry:
tail call void asm sideeffect "", "~{lr}"()
ret i32 0
}
define hidden i32 @ptr_auth_b() "branch-target-enforcement" {
entry:
tail call void asm sideeffect "", "~{lr}"()
ret i32 0
}
define hidden i32 @jump_table(i32 %a) "branch-target-enforcement" {
entry:
switch i32 %a, label %sw.epilog [
i32 1, label %sw.bb
i32 2, label %sw.bb1
i32 3, label %sw.bb2
i32 4, label %sw.bb3
i32 5, label %sw.bb4
]
sw.bb: ; preds = %entry
tail call void asm sideeffect "", ""()
br label %sw.epilog
sw.bb1: ; preds = %entry
tail call void asm sideeffect "", ""()
br label %sw.epilog
sw.bb2: ; preds = %entry
tail call void asm sideeffect "", ""()
br label %sw.epilog
sw.bb3: ; preds = %entry
tail call void asm sideeffect "", ""()
br label %sw.epilog
sw.bb4: ; preds = %entry
tail call void asm sideeffect "", ""()
br label %sw.epilog
sw.epilog: ; preds = %entry, %sw.bb4, %sw.bb3, %sw.bb2, %sw.bb1, %sw.bb
ret i32 0
}
@label_address.addr = internal unnamed_addr global i8* blockaddress(@label_address, %return), align 8
define hidden i32 @label_address() "branch-target-enforcement" {
entry:
%0 = load i8*, i8** @label_address.addr, align 8
indirectbr i8* %0, [label %return, label %lab2]
lab2: ; preds = %entry
br label %.split
return: ; preds = %entry
br label %.split
.split: ; preds = %lab2, %return
%merge = phi i8* [ blockaddress(@label_address, %lab2), %return ], [ blockaddress(@label_address, %return), %lab2 ]
%merge2 = phi i32 [ 1, %return ], [ 2, %lab2 ]
store i8* %merge, i8** @label_address.addr, align 8
ret i32 %merge2
}
define hidden i32 @label_address_entry() "branch-target-enforcement" {
entry:
%0 = load i8*, i8** @label_address.addr, align 8
indirectbr i8* %0, [label %return, label %lab2]
lab2: ; preds = %entry
br label %.split
return: ; preds = %entry
br label %.split
.split: ; preds = %lab2, %return
%merge = phi i8* [ blockaddress(@label_address, %lab2), %return ], [ blockaddress(@label_address, %return), %lab2 ]
%merge2 = phi i32 [ 1, %return ], [ 2, %lab2 ]
store i8* %merge, i8** @label_address.addr, align 8
ret i32 %merge2
}
...
---
# External function, could be addres-taken elsewhere so needs BTI JC.
name: simple_external
body: |
bb.0.entry:
; CHECK-LABEL: name: simple_external
; CHECK: HINT 34
; CHECK: RET
$w0 = ORRWrs $wzr, $wzr, 0
RET undef $lr, implicit killed $w0
---
# Internal function, not address-taken in this module, so no BTI needed.
name: simple_internal
body: |
bb.0.entry:
; CHECK-LABEL: name: simple_internal
; CHECK-NOT: HINT
; CHECK: RET
$w0 = ORRWrs $wzr, $wzr, 0
RET undef $lr, implicit killed $w0
---
# Function starts with PACIASP, which implicitly acts as BTI JC, so no change
# needed.
name: ptr_auth
stack:
- { id: 0, name: '', type: spill-slot, offset: -16, size: 8, alignment: 16,
stack-id: default, callee-saved-register: '$lr', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body: |
bb.0.entry:
liveins: $lr
; CHECK-LABEL: name: ptr_auth
; CHECK-NOT: HINT
; CHECK: frame-setup PACIASP
; CHECK-NOT: HINT
; CHECK: RETAA
frame-setup PACIASP implicit-def $lr, implicit killed $lr, implicit $sp
early-clobber $sp = frame-setup STRXpre killed $lr, $sp, -16 :: (store 8 into %stack.0)
INLINEASM &"", 1, 12, implicit-def dead early-clobber $lr
$w0 = ORRWrs $wzr, $wzr, 0
early-clobber $sp, $lr = frame-destroy LDRXpost $sp, 16 :: (load 8 from %stack.0)
RETAA implicit killed $w0
---
# Function starts with PACIBSP, which implicitly acts as BTI JC, so no change
# needed.
name: ptr_auth_b
stack:
- { id: 0, name: '', type: spill-slot, offset: -16, size: 8, alignment: 16,
stack-id: default, callee-saved-register: '$lr', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
body: |
bb.0.entry:
liveins: $lr
; CHECK-LABEL: name: ptr_auth_b
; CHECK-NOT: HINT
; CHECK: frame-setup PACIBSP
; CHECK-NOT: HINT
; CHECK: RETAB
frame-setup PACIBSP implicit-def $lr, implicit killed $lr, implicit $sp
early-clobber $sp = frame-setup STRXpre killed $lr, $sp, -16 :: (store 8 into %stack.0)
INLINEASM &"", 1, 12, implicit-def dead early-clobber $lr
$w0 = ORRWrs $wzr, $wzr, 0
early-clobber $sp, $lr = frame-destroy LDRXpost $sp, 16 :: (load 8 from %stack.0)
RETAB implicit killed $w0
---
# Function contains a jump table, so every target of the jump table must start
# with BTI J.
name: jump_table
jumpTable:
kind: block-address
entries:
- id: 0
blocks: [ '%bb.2', '%bb.3', '%bb.4', '%bb.5', '%bb.6' ]
body: |
bb.0.entry:
; CHECK-LABEL: name: jump_table
; CHECK: HINT 34
successors: %bb.7(0x15555555), %bb.1(0x6aaaaaab)
liveins: $w0
renamable $w8 = SUBWri killed renamable $w0, 1, 0, implicit-def $x8
dead $wzr = SUBSWri renamable $w8, 4, 0, implicit-def $nzcv
Bcc 8, %bb.7, implicit $nzcv
bb.1.entry:
; CHECK: bb.1.entry:
; CHECK-NOT: HINT
; CHECK: BR killed renamable $x8
successors: %bb.2(0x1999999a), %bb.3(0x1999999a), %bb.4(0x1999999a), %bb.5(0x1999999a), %bb.6(0x1999999a)
liveins: $x8
$x9 = ADRP target-flags(aarch64-page) %jump-table.0
renamable $x9 = ADDXri killed $x9, target-flags(aarch64-pageoff, aarch64-nc) %jump-table.0, 0
renamable $x8 = LDRXroX killed renamable $x9, killed renamable $x8, 0, 1 :: (load 8 from jump-table)
BR killed renamable $x8
bb.2.sw.bb:
; CHECK: bb.2.sw.bb
; CHECK-NEXT: HINT 36
$w0 = ORRWrs $wzr, $wzr, 0
INLINEASM &"", 1
RET undef $lr, implicit killed $w0
bb.3.sw.bb1:
; CHECK: bb.3.sw.bb1
; CHECK-NEXT: HINT 36
$w0 = ORRWrs $wzr, $wzr, 0
INLINEASM &"", 1
RET undef $lr, implicit killed $w0
bb.4.sw.bb2:
; CHECK: bb.4.sw.bb2
; CHECK-NEXT: HINT 36
$w0 = ORRWrs $wzr, $wzr, 0
INLINEASM &"", 1
RET undef $lr, implicit killed $w0
bb.5.sw.bb3:
; CHECK: bb.5.sw.bb3
; CHECK-NEXT: HINT 36
$w0 = ORRWrs $wzr, $wzr, 0
INLINEASM &"", 1
RET undef $lr, implicit killed $w0
bb.6.sw.bb4:
; CHECK: bb.6.sw.bb4
; CHECK-NEXT: successors: %bb.7(0x80000000)
; CHECK-NEXT: {{ }}
; CHECK-NEXT: HINT 36
successors: %bb.7(0x80000000)
INLINEASM &"", 1
bb.7.sw.epilog:
; CHECK: bb.7.sw.epilog:
; CHECK-NOT: HINT
; CHECK: RET
$w0 = ORRWrs $wzr, $wzr, 0
RET undef $lr, implicit killed $w0
---
# Function takes address of basic blocks, so they must start with BTI J.
name: label_address
body: |
bb.0.entry:
; CHECK-LABEL: label_address
; CHECK: bb.0.entry:
; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000)
; CHECK-NEXT: {{ }}
; CHECK-NEXT: HINT 34
; CHECK: BR killed renamable $x9
successors: %bb.1(0x40000000), %bb.2(0x40000000)
renamable $x8 = ADRP target-flags(aarch64-page) @label_address.addr
renamable $x9 = LDRXui renamable $x8, target-flags(aarch64-pageoff, aarch64-nc) @label_address.addr :: (dereferenceable load 8 from @label_address.addr)
BR killed renamable $x9
bb.1.return (address-taken):
; CHECK: bb.1.return (address-taken):
; CHECK-NEXT: HINT 36
liveins: $x8
$x9 = ADRP target-flags(aarch64-page) blockaddress(@label_address, %ir-block.lab2)
renamable $w0 = ORRWri $wzr, 0
renamable $x9 = ADDXri killed $x9, target-flags(aarch64-pageoff, aarch64-nc) blockaddress(@label_address, %ir-block.lab2), 0
STRXui killed renamable $x9, killed renamable $x8, target-flags(aarch64-pageoff, aarch64-nc) @label_address.addr :: (store 8 into @label_address.addr)
RET undef $lr, implicit killed $w0
bb.2.lab2 (address-taken):
; CHECK: bb.2.lab2 (address-taken):
; CHECK-NEXT: HINT 36
liveins: $x8
$x9 = ADRP target-flags(aarch64-page) blockaddress(@label_address, %ir-block.return)
renamable $w0 = ORRWri $wzr, 1984
renamable $x9 = ADDXri killed $x9, target-flags(aarch64-pageoff, aarch64-nc) blockaddress(@label_address, %ir-block.return), 0
STRXui killed renamable $x9, killed renamable $x8, target-flags(aarch64-pageoff, aarch64-nc) @label_address.addr :: (store 8 into @label_address.addr)
RET undef $lr, implicit killed $w0
---
# Function takes address of the entry block, so the entry block needs a BTI JC.
name: label_address_entry
body: |
bb.0.entry (address-taken):
; CHECK-LABEL: label_address_entry
; CHECK: bb.0.entry (address-taken):
; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000)
; CHECK-NEXT: {{ }}
; CHECK-NEXT: HINT 38
; CHECK: BR killed renamable $x9
successors: %bb.1(0x40000000), %bb.2(0x40000000)
renamable $x8 = ADRP target-flags(aarch64-page) @label_address.addr
renamable $x9 = LDRXui renamable $x8, target-flags(aarch64-pageoff, aarch64-nc) @label_address.addr :: (dereferenceable load 8 from @label_address.addr)
BR killed renamable $x9
bb.1.return (address-taken):
; CHECK: bb.1.return (address-taken):
; CHECK-NEXT: HINT 36
liveins: $x8
$x9 = ADRP target-flags(aarch64-page) blockaddress(@label_address, %ir-block.entry)
renamable $w0 = ORRWri $wzr, 0
renamable $x9 = ADDXri killed $x9, target-flags(aarch64-pageoff, aarch64-nc) blockaddress(@label_address, %ir-block.entry), 0
STRXui killed renamable $x9, killed renamable $x8, target-flags(aarch64-pageoff, aarch64-nc) @label_address.addr :: (store 8 into @label_address.addr)
RET undef $lr, implicit killed $w0
bb.2.lab2:
; CHECK: bb.2.lab2:
; CHECK-NOT: HINT
liveins: $x8
$x9 = ADRP target-flags(aarch64-page) blockaddress(@label_address, %ir-block.return)
renamable $w0 = ORRWri $wzr, 1984
renamable $x9 = ADDXri killed $x9, target-flags(aarch64-pageoff, aarch64-nc) blockaddress(@label_address, %ir-block.return), 0
STRXui killed renamable $x9, killed renamable $x8, target-flags(aarch64-pageoff, aarch64-nc) @label_address.addr :: (store 8 into @label_address.addr)
RET undef $lr, implicit killed $w0
...
|