Skip to content

[llvm][MC][ARM][Assembly] Emit relocations for LDRs #72873

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
merged 5 commits into from
Nov 25, 2023
Merged

[llvm][MC][ARM][Assembly] Emit relocations for LDRs #72873

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
7515480
[llvm][MC][ARM][Assembly] Emit relocs for LDRs
eleanor-arm Nov 10, 2023
65a1037
Fixup: Fix clang-format
eleanor-arm Nov 20, 2023
c267cca
Fixup: Comment in imm8-relocs test
eleanor-arm Nov 20, 2023
d5ec983
fixup: simplify checks & add more label+-imm test coverage
eleanor-arm Nov 23, 2023
06f74e6
Fixup: use regex to pick up both decimal and hex format
eleanor-arm Nov 23, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
7 changes: 4 additions & 3 deletions llvm/lib/Target/ARM/MCTargetDesc/ARMAsmBackend.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -74,10 +74,11 @@ const MCFixupKindInfo &ARMAsmBackend::getFixupKindInfo(MCFixupKind Kind) const {
// ARMFixupKinds.h.
//
// Name Offset (bits) Size (bits) Flags
{"fixup_arm_ldst_pcrel_12", 0, 32, IsPCRelConstant},
{"fixup_arm_ldst_pcrel_12", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
{"fixup_t2_ldst_pcrel_12", 0, 32,
IsPCRelConstant | MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
{"fixup_arm_pcrel_10_unscaled", 0, 32, IsPCRelConstant},
MCFixupKindInfo::FKF_IsPCRel |
MCFixupKindInfo::FKF_IsAlignedDownTo32Bits},
{"fixup_arm_pcrel_10_unscaled", 0, 32, MCFixupKindInfo::FKF_IsPCRel},
{"fixup_arm_pcrel_10", 0, 32, IsPCRelConstant},
{"fixup_t2_pcrel_10", 0, 32,
MCFixupKindInfo::FKF_IsPCRel |
Expand Down
6 changes: 6 additions & 0 deletions llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -158,6 +158,12 @@ unsigned ARMELFObjectWriter::GetRelocTypeInner(const MCValue &Target,
default:
return ELF::R_ARM_THM_CALL;
}
case ARM::fixup_arm_ldst_pcrel_12:
return ELF::R_ARM_LDR_PC_G0;
case ARM::fixup_arm_pcrel_10_unscaled:
return ELF::R_ARM_LDRS_PC_G0;
case ARM::fixup_t2_ldst_pcrel_12:
return ELF::R_ARM_THM_PC12;
case ARM::fixup_bf_target:
return ELF::R_ARM_THM_BF16;
case ARM::fixup_bfc_target:
Expand Down
42 changes: 42 additions & 0 deletions llvm/test/MC/ARM/pcrel-arm-ldr-imm8-relocs.s
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,42 @@
@ RUN: llvm-mc -filetype=obj -triple=armv7 %s -o %t
@ RUN: llvm-readelf -r %t | FileCheck %s --check-prefix=ARM
@ RUN: llvm-objdump -d --triple=armv7 %t | FileCheck %s --check-prefix=ARM_ADDEND

@ ARM: R_ARM_LDRS_PC_G0
@ ARM: R_ARM_LDRS_PC_G0
@ ARM: R_ARM_LDRS_PC_G0
@ ARM: R_ARM_LDRS_PC_G0
@ ARM: R_ARM_LDRS_PC_G0
@ ARM: R_ARM_LDRS_PC_G0

// The value format is decimal in these specific cases, but it's hex for other
// ldr instructions. These checks are valid for both formats.

@ ARM_ADDEND: r0, [pc, #-{{(0x)?}}8]
@ ARM_ADDEND: r0, [pc, #-{{(0x)?}}8]
@ ARM_ADDEND: r0, [pc, #-{{(0x)?}}8]
@ ARM_ADDEND: r0, [pc, #-{{16|0x10}}]
@ ARM_ADDEND: r0, [pc, #-{{16|0x10}}]
@ ARM_ADDEND: r0, [pc]

.arm
.section .text.bar, "ax"
.balign 4
.global bar
.type bar, %function
bar:
ldrh r0, foo
ldrsb r0, foo
ldrsh r0, foo
ldrh r0, just_after-8
ldrsb r0, just_after-8
ldrsh r0, foo+8
bx lr

.section .data.foo, "a", %progbits
.balign 4
.global foo
foo:
.word 0x11223344, 0x55667788
just_after:
.word 0x9900aabb, 0xccddeeff
8 changes: 2 additions & 6 deletions llvm/test/MC/ARM/pcrel-global.s
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -9,21 +9,18 @@
@ DISASM-LABEL: <bar>:
@ DISASM-NEXT: adr.w r0, #-4
@ DISASM-NEXT: adr.w r0, #-8
@ DISASM-NEXT: ldr.w pc, [pc, #-0xc] @ 0x10 <bar>
@ DISASM-NEXT: ldr r0, [pc, #0x0] @ 0x20 <bar+0x10>
@ DISASM-NEXT: ldr r0, [pc, #0x0] @ 0x14 <bar+0xc>
@ DISASM-NEXT: add r0, pc
@ DISASM-NEXT: .word 0xffffffef
@ DISASM-NEXT: .word 0xfffffff3
@@ GNU assembler creates an R_ARM_REL32 referencing bar.
@ DISASM-NOT: {{.}}

.syntax unified

.globl foo
foo:
ldrd r0, r1, foo @ arm_pcrel_10_unscaled
vldr d0, foo @ arm_pcrel_10
adr r2, foo @ arm_adr_pcrel_12
ldr r0, foo @ arm_ldst_pcrel_12

.thumb
.thumb_func
Expand All @@ -32,7 +29,6 @@ ldr r0, foo @ arm_ldst_pcrel_12
bar:
adr r0, bar @ thumb_adr_pcrel_10
adr.w r0, bar @ t2_adr_pcrel_12
ldr.w pc, bar @ t2_ldst_pcrel_12

ldr r0, .LCPI
.LPC0_1:
Expand Down
46 changes: 46 additions & 0 deletions llvm/test/MC/ARM/pcrel-ldr-relocs.s
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,46 @@
@ RUN: llvm-mc -filetype=obj -triple=armv7 %s -o %t
@ RUN: llvm-readelf -r %t | FileCheck %s --check-prefix=ARM
@ RUN: llvm-objdump -d --triple=armv7 %t | FileCheck %s --check-prefix=ARM_ADDEND
@ RUN: llvm-mc -filetype=obj -triple=thumbv7 %s -o %t
@ RUN: llvm-readelf -r %t | FileCheck %s --check-prefix=THUMB
@ RUN: llvm-objdump -d --triple=thumbv7 %t | FileCheck %s --check-prefix=THUMB_ADDEND

@ ARM: R_ARM_LDR_PC_G0
@ ARM: R_ARM_LDR_PC_G0
@ ARM: R_ARM_LDR_PC_G0
@ ARM: R_ARM_LDR_PC_G0

@ ARM_ADDEND: r0, [pc, #-0x8]
@ ARM_ADDEND: r0, [pc, #-0x8]
@ ARM_ADDEND: r0, [pc, #-0x10]
@ ARM_ADDEND: r0, [pc]

@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12

@ THUMB_ADDEND: r0, [pc, #-0x4]
@ THUMB_ADDEND: r0, [pc, #-0x4]
@ THUMB_ADDEND: r0, [pc, #-0xc]
@ THUMB_ADDEND: r0, [pc, #0x4]

.section .text.bar, "ax"
.balign 4
.global bar
.type bar, %function
bar:
ldr r0, foo1
ldrb r0, foo1
ldr r0, foo2-8
ldrb r0, foo1+8
bx lr

.section .data.foo, "a", %progbits
.balign 4
.global foo1
.global foo2
foo1:
.word 0x11223344, 0x55667788
foo2:
.word 0x99aabbcc, 0xddeeff00
41 changes: 41 additions & 0 deletions llvm/test/MC/ARM/pcrel-thumb-ldr2-relocs.s
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -0,0 +1,41 @@
@ RUN: llvm-mc -filetype=obj -triple=thumbv7 %s -o %t
@ RUN: llvm-readelf -r %t | FileCheck %s --check-prefix=THUMB
@ RUN: llvm-objdump -d --triple=thumbv7 %t | FileCheck %s --check-prefix=THUMB_ADDEND

@ All the ldr variants produce a relocation
@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12
@ THUMB: R_ARM_THM_PC12

@ THUMB_ADDEND: r0, [pc, #-0x4]
@ THUMB_ADDEND: r0, [pc, #-0x4]
@ THUMB_ADDEND: r0, [pc, #-0x4]
@ THUMB_ADDEND: r0, [pc, #0x4]
@ THUMB_ADDEND: r0, [pc, #-0xc]
@ THUMB_ADDEND: r0, [pc, #0x4]

.thumb
.section .text.bar, "ax"
.balign 4
.global bar
.type bar, %function
bar:
ldrh r0, foo1
ldrsb r0, foo1
ldrsh r0, foo1
ldrh r0, foo1+8
ldrsb r0, foo2-8
ldrsh r0, foo1+8
bx lr

.section .data.foo, "a", %progbits
.balign 4
.global foo1
.global foo2
foo1:
.word 0x11223344, 0x55667788
foo2:
.word 0x9900aabb, 0xccddeeff
1 change: 0 additions & 1 deletion llvm/test/MC/ARM/thumb1-relax-ldrlit.s
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,6 +1,5 @@
@ RUN: not llvm-mc -triple thumbv6m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
@ RUN: not llvm-mc -triple thumbv7m-none-macho -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s
@ RUN: not llvm-mc -triple thumbv7m-none-eabi -filetype=obj -o /dev/null %s 2>&1 | FileCheck --check-prefix=CHECK-ERROR %s

.global func1
_func1:
Expand Down