da083e358e
This re-applies #96164 after revert in #102434. Support the following relocations and assembly operators: - `R_AARCH64_AUTH_ADR_GOT_PAGE` (`:got_auth:` for `adrp`) - `R_AARCH64_AUTH_LD64_GOT_LO12_NC` (`:got_auth_lo12:` for `ldr`) - `R_AARCH64_AUTH_GOT_ADD_LO12_NC` (`:got_auth_lo12:` for `add`) `LOADgotAUTH` pseudo-instruction is introduced which is later expanded to actual instruction sequence like the following. ``` adrp x16, :got_auth:sym add x16, x16, :got_auth_lo12:sym ldr x0, [x16] autia x0, x16 ``` If a resign is requested, like below, `LOADgotPAC` pseudo is used, and GOT load is lowered similarly to `LOADgotAUTH`. ``` @var = global i32 0 define ptr @resign_globalvar() { ret ptr ptrauth (ptr @var, i32 3, i64 43) } ``` If FPAC bit is not set and auth instruction is emitted, a check+trap sequence similar to one used for `AUT` pseudo is emitted to ensure auth success. Both SelectionDAG and GlobalISel are suppported. For FastISel, we fall back to SelectionDAG. Tests starting with 'ptrauth-' have corresponding variants w/o this prefix. See also specification https://github.com/ARM-software/abi-aa/blob/main/pauthabielf64/pauthabielf64.rst#appendix-signed-got
75 lines
2.9 KiB
LLVM
75 lines
2.9 KiB
LLVM
; RUN: llc -mtriple=aarch64-none-linux-gnu -global-isel=0 -fast-isel=0 -relocation-model=pic \
|
|
; RUN: -mattr=+pauth -mattr=+fpac -o - %s | FileCheck --check-prefixes=CHECK,NOTRAP %s
|
|
; RUN: llc -mtriple=aarch64-none-linux-gnu -global-isel=0 -fast-isel=0 -relocation-model=pic \
|
|
; RUN: -mattr=+pauth -o - %s | FileCheck --check-prefixes=CHECK,TRAP %s
|
|
|
|
; RUN: llc -mtriple=aarch64-none-linux-gnu -global-isel=0 -fast-isel=1 -relocation-model=pic \
|
|
; RUN: -mattr=+pauth -mattr=+fpac -o - %s | FileCheck --check-prefixes=CHECK,NOTRAP %s
|
|
; RUN: llc -mtriple=aarch64-none-linux-gnu -global-isel=0 -fast-isel=1 -relocation-model=pic \
|
|
; RUN: -mattr=+pauth -o - %s | FileCheck --check-prefixes=CHECK,TRAP %s
|
|
|
|
; RUN: llc -mtriple=aarch64-none-linux-gnu -global-isel=1 -global-isel-abort=1 -relocation-model=pic \
|
|
; RUN: -mattr=+pauth -mattr=+fpac -o - %s | FileCheck --check-prefixes=CHECK,NOTRAP %s
|
|
; RUN: llc -mtriple=aarch64-none-linux-gnu -global-isel=1 -global-isel-abort=1 -relocation-model=pic \
|
|
; RUN: -mattr=+pauth -o - %s | FileCheck --check-prefixes=CHECK,TRAP %s
|
|
|
|
;; Note: for FastISel, we fall back to SelectionDAG
|
|
|
|
declare extern_weak dso_local i32 @var()
|
|
|
|
define ptr @foo() {
|
|
; The usual ADRP/ADD pair can't be used for a weak reference because it must
|
|
; evaluate to 0 if the symbol is undefined. We use a GOT entry for PIC
|
|
; otherwise a litpool entry.
|
|
ret ptr @var
|
|
|
|
; CHECK-LABEL: foo:
|
|
; CHECK: adrp x17, :got_auth:var
|
|
; CHECK-NEXT: add x17, x17, :got_auth_lo12:var
|
|
; NOTRAP-NEXT: ldr x0, [x17]
|
|
; NOTRAP-NEXT: cbz x0, .Lundef_weak0
|
|
; NOTRAP-NEXT: autia x0, x17
|
|
; TRAP-NEXT: ldr x16, [x17]
|
|
; TRAP-NEXT: cbz x16, .Lundef_weak0
|
|
; TRAP-NEXT: autia x16, x17
|
|
; CHECK-NEXT: .Lundef_weak0:
|
|
; TRAP-NEXT: mov x17, x16
|
|
; TRAP-NEXT: xpaci x17
|
|
; TRAP-NEXT: cmp x16, x17
|
|
; TRAP-NEXT: b.eq .Lauth_success_0
|
|
; TRAP-NEXT: brk #0xc470
|
|
; TRAP-NEXT: .Lauth_success_0:
|
|
; TRAP-NEXT: mov x0, x16
|
|
; CHECK-NEXT: ret
|
|
}
|
|
|
|
@arr_var = extern_weak global [10 x i32]
|
|
|
|
define ptr @bar() {
|
|
%addr = getelementptr [10 x i32], ptr @arr_var, i32 0, i32 5
|
|
ret ptr %addr
|
|
|
|
; CHECK-LABEL: bar:
|
|
; CHECK: adrp x17, :got_auth:arr_var
|
|
; CHECK-NEXT: add x17, x17, :got_auth_lo12:arr_var
|
|
; NOTRAP-NEXT: ldr x8, [x17]
|
|
; NOTRAP-NEXT: cbz x8, .Lundef_weak1
|
|
; NOTRAP-NEXT: autda x8, x17
|
|
; TRAP-NEXT: ldr x16, [x17]
|
|
; TRAP-NEXT: cbz x16, .Lundef_weak1
|
|
; TRAP-NEXT: autda x16, x17
|
|
; CHECK-NEXT: .Lundef_weak1:
|
|
; TRAP-NEXT: mov x17, x16
|
|
; TRAP-NEXT: xpacd x17
|
|
; TRAP-NEXT: cmp x16, x17
|
|
; TRAP-NEXT: b.eq .Lauth_success_1
|
|
; TRAP-NEXT: brk #0xc472
|
|
; TRAP-NEXT: .Lauth_success_1:
|
|
; TRAP-NEXT: mov x8, x16
|
|
; CHECK-NEXT: add x0, x8, #20
|
|
; CHECK-NEXT: ret
|
|
}
|
|
|
|
!llvm.module.flags = !{!0}
|
|
!0 = !{i32 8, !"ptrauth-elf-got", i32 1}
|