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Differential D107951

[ELF] Produce DT_RISCV_VARIANT_CC
ClosedPublic

Authored by MaskRay on Aug 12 2021, 1:01 AM.

Details

Reviewers
fakepaper56
kito-cheng
Commits
rGb067aa56cec3: [ELF] Produce DT_RISCV_VARIANT_CC
Summary

https://github.com/riscv/riscv-elf-psabi-doc/pull/190 introduced STO_RISCV_VARIANT_CC.
The linker should do:

  • Copy the STO_RISCV_VARIANT_CC bit to .symtab/.dynsym: already fulfilled after 82ed93ea0552c8f82df05859ee93e70b71c4e65d
  • Produce DT_RISCV_VARIANT_CC if at least one R_RISCV_JUMP_SLOT relocation references a symbol with the STO_RISCV_VARIANT_CC bit. Done by this patch.

Diff Detail

Event Timeline

MaskRay created this revision.Aug 12 2021, 1:01 AM
Herald added subscribers: vkmr, frasercrmck, evandro and 26 others. · View Herald TranscriptAug 12 2021, 1:01 AM
MaskRay requested review of this revision.Aug 12 2021, 1:01 AM
Herald added a project: Restricted Project. · View Herald TranscriptAug 12 2021, 1:01 AM
Herald added a subscriber: llvm-commits. · View Herald Transcript
Harbormaster completed remote builds in B119207: Diff 365929.Aug 12 2021, 1:12 AM
MaskRay added a parent revision: D138352: [RISCV] Support .variant_cc directive for the assembler..Dec 4 2022, 11:22 AM
Herald added a project: Restricted Project. · View Herald TranscriptDec 4 2022, 11:22 AM
Herald added subscribers: sunshaoce, • pcwang-thead, eopXD and 2 others. · View Herald Transcript
MaskRay updated this revision to Diff 479937.Dec 4 2022, 11:40 AM
MaskRay retitled this revision from [ELF] Handle STO_RISCV_VARIANT_PCS to [ELF] Handle STO_RISCV_VARIANT_CC.
MaskRay edited the summary of this revision. (Show Details)

rebase

MaskRay added reviewers: fakepaper56, kito-cheng.Dec 4 2022, 11:40 AM
MaskRay updated this revision to Diff 479938.Dec 4 2022, 11:56 AM

simplify test

Harbormaster completed remote builds in B200990: Diff 479938.Dec 4 2022, 12:10 PM
kito-cheng accepted this revision.Dec 4 2022, 6:45 PM

LGTM, thanks for complete the lld part of STO_RISCV_VARIANT_CC !

lld/ELF/SyntheticSections.cpp
1426–1429

nit: Maybe llvm::any_of? although use llvm::_find_if can archive same purpose, but any_of might improve readable here?

This revision is now accepted and ready to land.Dec 4 2022, 6:45 PM
MaskRay updated this revision to Diff 479972.Dec 4 2022, 9:00 PM
MaskRay marked an inline comment as done.

use any_of

MaskRay edited the summary of this revision. (Show Details)Dec 4 2022, 9:01 PM
MaskRay updated this revision to Diff 479974.Dec 4 2022, 9:05 PM
MaskRay retitled this revision from [ELF] Handle STO_RISCV_VARIANT_CC to [ELF] Produce DT_RISCV_VARIANT_CC.
MaskRay edited the summary of this revision. (Show Details)

add release note

MaskRay updated this revision to Diff 479975.Dec 4 2022, 9:07 PM

fix release note

This revision was landed with ongoing or failed builds.Dec 4 2022, 9:08 PM
Closed by commit rGb067aa56cec3: [ELF] Produce DT_RISCV_VARIANT_CC (authored by MaskRay). · Explain Why
This revision was automatically updated to reflect the committed changes.
MaskRay added a commit: rGb067aa56cec3: [ELF] Produce DT_RISCV_VARIANT_CC.
Harbormaster completed remote builds in B201016: Diff 479975.Dec 4 2022, 9:31 PM
MaskRay added inline comments.Dec 4 2022, 9:57 PM
lld/ELF/SyntheticSections.cpp
1426–1429

Thanks for the suggestion!

Revision Contents

PathSize
lld/
ELF/
8 lines
test/
ELF/
130 lines

Diff 479937

lld/ELF/SyntheticSections.cpp

Show First 20 Lines • Show All 1,414 Lines • ▼ Show 20 Lines case EM_SPARCV9:
addInSec(DT_PLTGOT, *in.plt); addInSec(DT_PLTGOT, *in.plt);
break; break;
case EM_AARCH64: case EM_AARCH64:
if (llvm::find_if(in.relaPlt->relocs, [](const DynamicReloc &r) { if (llvm::find_if(in.relaPlt->relocs, [](const DynamicReloc &r) {
return r.type == target->pltRel && return r.type == target->pltRel &&
r.sym->stOther & STO_AARCH64_VARIANT_PCS; r.sym->stOther & STO_AARCH64_VARIANT_PCS;
}) != in.relaPlt->relocs.end()) }) != in.relaPlt->relocs.end())
addInt(DT_AARCH64_VARIANT_PCS, 0); addInt(DT_AARCH64_VARIANT_PCS, 0);
addInSec(DT_PLTGOT, *in.gotPlt);
break;
case EM_RISCV:
if (llvm::find_if(in.relaPlt->relocs, [](const DynamicReloc &r) {
return r.type == target->pltRel &&
(r.sym->stOther & STO_RISCV_VARIANT_CC);
}) != in.relaPlt->relocs.end())
kito-chengUnsubmitted
Done
ReplyInline Actions

nit: Maybe llvm::any_of? although use llvm::_find_if can archive same purpose, but any_of might improve readable here?

kito-cheng: nit: Maybe `llvm::any_of`? although use `llvm::_find_if` can archive same purpose, but `any_of`…
MaskRayAuthorUnsubmitted
Done
ReplyInline Actions

Thanks for the suggestion!

MaskRay: Thanks for the suggestion!
addInt(DT_RISCV_VARIANT_CC, 0);
[[fallthrough]]; [[fallthrough]];
default: default:
addInSec(DT_PLTGOT, *in.gotPlt); addInSec(DT_PLTGOT, *in.gotPlt);
break; break;
} }
addInt(DT_PLTREL, config->isRela ? DT_RELA : DT_REL); addInt(DT_PLTREL, config->isRela ? DT_RELA : DT_REL);
} }
▲ Show 20 Lines • Show All 2,528 Lines • Show Last 20 Lines

lld/test/ELF/riscv-variant-cc.s

  • This file was added.
# REQUIRES: riscv
# RUN: rm -rf %t && split-file %s %t
# RUN: llvm-mc -filetype=obj -triple=riscv32 %t/test1 -o %t.o
# RUN: ld.lld %t.o --shared -o %t.so
# RUN: llvm-readelf --dynamic-table %t.so | FileCheck --check-prefix T1-CCDYN %s
# RUN: llvm-readelf --symbols %t.so | FileCheck --check-prefix T1-CCSYM %s
# T1-CCDYN-NOT: (RISCV_VARIANT_CC)
# T1-CCSYM: Symbol table '.dynsym'
# T1-CCSYM: 0 NOTYPE GLOBAL DEFAULT [VARIANT_CC] [[#]] func_global_def
# RUN: llvm-mc -filetype=obj -triple=riscv64 %t/test2 -o %t.o
# RUN: ld.lld %t.o --shared -o %t.so
# RUN: llvm-readelf --dynamic-table %t.so | FileCheck --check-prefix T2-CCDYN %s
# RUN: llvm-readelf --symbols %t.so | FileCheck --check-prefix T2-CCSYM %s
# T2-CCDYN: 0x0000000070000001 (RISCV_VARIANT_CC) 0
# T2-CCSYM: Symbol table '.dynsym'
# T2-CCSYM: 0 NOTYPE GLOBAL DEFAULT [VARIANT_CC] [[#]] func_global_def
# RUN: llvm-mc -filetype=obj -triple=riscv32 %t/test3 -o %t.o
# RUN: ld.lld %t.o --shared -o %t.so
# RUN: llvm-readelf --dynamic-table %t.so | FileCheck --check-prefix T3-CCDYN %s
# RUN: llvm-readelf --symbols %t.so | FileCheck --check-prefix T3-CCSYM %s
# T3-CCDYN: 0x70000001 (RISCV_VARIANT_CC) 0
# T3-CCSYM: Symbol table '.dynsym'
# T3-CCSYM: 0 IFUNC GLOBAL DEFAULT [VARIANT_CC] UND ifunc_global_def
# T3-CCSYM: 0 NOTYPE GLOBAL DEFAULT [[#]] func_global_def
# RUN: llvm-mc -filetype=obj -triple=riscv64 %t/test4 -o %t.o
# RUN: ld.lld %t.o --shared -o %t.so
# RUN: llvm-readelf --dynamic-table %t.so | FileCheck --check-prefix T4-CCDYN %s
# RUN: llvm-readelf --symbols %t.so | FileCheck --check-prefix T4-CCSYM %s
# T4-CCDYN-NOT: 0x0000000070000001 (RISCV_VARIANT_CC) 0
# T4-CCSYM: Symbol table '.dynsym'
# T4-CCSYM: 0 IFUNC GLOBAL DEFAULT [VARIANT_CC] [[#]] ifunc_global_def
# RUN: llvm-mc -filetype=obj -triple=riscv64 %t/test5 -o %t.o
# RUN: ld.lld %t.o --shared -o %t.so
# RUN: llvm-readelf --symbols %t.so | FileCheck --check-prefix T5-CCSYM %s
# T5-CCSYM: Symbol table '.dynsym'
# T5-CCSYM: 0 NOTYPE GLOBAL DEFAULT [VARIANT_CC] UND func_global_undef
# T5-CCSYM-NEXT: 0 NOTYPE GLOBAL DEFAULT [VARIANT_CC] [[#]] func_global_def
# T5-CCSYM-NEXT: 0 IFUNC GLOBAL DEFAULT [VARIANT_CC] [[#]] ifunc_global_def
# T5-CCSYM: Symbol table '.symtab' contains 9 entries:
# T5-CCSYM: 0 NOTYPE LOCAL DEFAULT [VARIANT_CC] [[#]] func_local
# T5-CCSYM-NEXT: 0 IFUNC LOCAL DEFAULT [VARIANT_CC] [[#]] ifunc_local
# T5-CCSYM: 0 NOTYPE LOCAL HIDDEN [VARIANT_CC] [[#]] func_global_hidden
# T5-CCSYM-NEXT: 0 IFUNC LOCAL HIDDEN [VARIANT_CC] [[#]] ifunc_global_hidden
# T5-CCSYM: 0 NOTYPE GLOBAL DEFAULT [VARIANT_CC] [[#]] func_global_def
# T5-CCSYM-NEXT: 0 NOTYPE GLOBAL DEFAULT [VARIANT_CC] UND func_global_undef
# T5-CCSYM-NEXT: 0 IFUNC GLOBAL DEFAULT [VARIANT_CC] [[#]] ifunc_global_def
#--- test1
## An object with a variant_pcs symbol but without a R_RISCV_JMP_SLOT
## should not generate a DT_RISCV_VARIANT_CC.
.text
.global func_global_def
.variant_cc func_global_def
func_global_def:
ret
#--- test2
## An object with a variant_cc symbol and with a R_RISCV_JMP_SLOT
## should generate a DT_RISCV_VARIANT_CC.
.text
.global func_global_def
.variant_cc func_global_def
func_global_def:
call func_global_def
#--- test3
## Same as before, but targeting a GNU IFUNC.
.text
.global ifunc_global_def
.global func_global_def
.variant_cc ifunc_global_def
.type ifunc_global_def, %gnu_indirect_function
func_global_def:
call ifunc_global_def
#--- test4
## An object with a variant_cc symbol and with a R_RISCV_IRELATIVE
## should not generate a DT_RISCV_VARIANT_CC.
.text
.global ifunc_global_def
.global func_global_def
.variant_cc ifunc_global_def
.type ifunc_global_def, %gnu_indirect_function
ifunc_global_def:
call func_global_def
#--- test5
## Check if STO_RISCV_VARIANT_CC is kept on symbol st_other for both undef,
## local, and hidden visibility.
.text
.global func_global_def, func_global_undef, func_global_hidden
.global ifunc_global_def, ifunc_global_hidden
.local func_local
.hidden func_global_hidden, ifunc_global_hidden
.type ifunc_global_def, %gnu_indirect_function
.type ifunc_global_hidden, %gnu_indirect_function
.type ifunc_local, %gnu_indirect_function
.variant_cc func_global_def
.variant_cc func_global_undef
.variant_cc func_global_hidden
.variant_cc func_local
.variant_cc ifunc_global_def
.variant_cc ifunc_global_hidden
.variant_cc ifunc_local
func_global_def:
func_global_hidden:
func_local:
ifunc_global_def:
ifunc_global_hidden:
ifunc_local:
ret