MC: Emit symbols for R_X86_64_PLT32 relocation pointing to symbols with non-zero values. #138795
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Created using spr 1.3.6-beta.1
llvmbot
added
backend:ARM
backend:AArch64
backend:RISC-V
backend:PowerPC
backend:Sparc
backend:SystemZ
backend:X86
mc
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@llvm/pr-subscribers-backend-aarch64 @llvm/pr-subscribers-backend-risc-v Author: Peter Collingbourne (pcc) ChangesIn the following case: .section .text.a,"ax",@progbits .text we previously emitted an R_X86_64_PLT32 relocation for the jmp Full diff: https://github.com/llvm/llvm-project/pull/138795.diff 17 Files Affected:
diff --git a/llvm/include/llvm/MC/MCELFObjectWriter.h b/llvm/include/llvm/MC/MCELFObjectWriter.h
index f0f2dca4738e4..76a5ec6346770 100644
--- a/llvm/include/llvm/MC/MCELFObjectWriter.h
+++ b/llvm/include/llvm/MC/MCELFObjectWriter.h
@@ -88,7 +88,8 @@ class MCELFObjectTargetWriter : public MCObjectTargetWriter {
virtual unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const = 0;
- virtual bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ virtual bool needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val, const MCSymbol &Sym,
unsigned Type) const;
virtual void sortRelocs(const MCAssembler &Asm,
diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index 5c39daef9c98d..264a56f0966eb 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -1303,7 +1303,7 @@ bool ELFObjectWriter::useSectionSymbol(const MCAssembler &Asm,
if (Asm.isThumbFunc(Sym))
return false;
- return !TargetObjectWriter->needsRelocateWithSymbol(Val, *Sym, Type);
+ return !TargetObjectWriter->needsRelocateWithSymbol(Asm, Val, *Sym, Type);
}
bool ELFObjectWriter::checkRelocation(MCContext &Ctx, SMLoc Loc,
diff --git a/llvm/lib/MC/MCELFObjectTargetWriter.cpp b/llvm/lib/MC/MCELFObjectTargetWriter.cpp
index 49cca57d3aaa3..5cfac5ba093e7 100644
--- a/llvm/lib/MC/MCELFObjectTargetWriter.cpp
+++ b/llvm/lib/MC/MCELFObjectTargetWriter.cpp
@@ -17,7 +17,8 @@ MCELFObjectTargetWriter::MCELFObjectTargetWriter(bool Is64Bit_, uint8_t OSABI_,
: OSABI(OSABI_), ABIVersion(ABIVersion_), EMachine(EMachine_),
HasRelocationAddend(HasRelocationAddend_), Is64Bit(Is64Bit_) {}
-bool MCELFObjectTargetWriter::needsRelocateWithSymbol(const MCValue &,
+bool MCELFObjectTargetWriter::needsRelocateWithSymbol(const MCAssembler &,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
return false;
diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
index 53acf7dd61054..20d63415e768e 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
@@ -38,7 +38,8 @@ class AArch64ELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
bool IsILP32;
};
@@ -534,7 +535,8 @@ unsigned AArch64ELFObjectWriter::getRelocType(MCContext &Ctx,
llvm_unreachable("Unimplemented fixup -> relocation");
}
-bool AArch64ELFObjectWriter::needsRelocateWithSymbol(const MCValue &Val,
+bool AArch64ELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val,
const MCSymbol &,
unsigned) const {
// For memory-tagged symbols, ensure that the relocation uses the symbol. For
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
index 9fb681611594a..0dd71d55616ef 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
@@ -39,7 +39,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -50,7 +51,8 @@ ARMELFObjectWriter::ARMELFObjectWriter(uint8_t OSABI)
ELF::EM_ARM,
/*HasRelocationAddend*/ false) {}
-bool ARMELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool ARMELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
// FIXME: This is extremely conservative. This really needs to use an
diff --git a/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp b/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
index d424399ce6bc9..89df9d1b6bdce 100644
--- a/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
+++ b/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
@@ -29,7 +29,8 @@ class CSKYELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -167,7 +168,8 @@ unsigned CSKYELFObjectWriter::getRelocType(MCContext &Ctx,
}
}
-bool CSKYELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool CSKYELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &,
unsigned Type) const {
switch (V.getSpecifier()) {
diff --git a/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp b/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
index a21518e44116e..744c4427fbec6 100644
--- a/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
+++ b/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
@@ -26,7 +26,8 @@ class LanaiELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -72,7 +73,8 @@ unsigned LanaiELFObjectWriter::getRelocType(MCContext & /*Ctx*/,
return Type;
}
-bool LanaiELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool LanaiELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
index 5b6ecc1e8bc1f..55e9eef6de94e 100644
--- a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
+++ b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
@@ -26,7 +26,8 @@ class LoongArchELFObjectWriter : public MCELFObjectTargetWriter {
~LoongArchELFObjectWriter() override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override {
return EnableRelax;
}
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index 83073e4243414..acee6413a5651 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -50,7 +50,8 @@ class MipsELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
void sortRelocs(const MCAssembler &Asm,
std::vector<ELFRelocationEntry> &Relocs) override;
@@ -444,15 +445,16 @@ void MipsELFObjectWriter::sortRelocs(const MCAssembler &Asm,
Relocs[CopyTo++] = R.R;
}
-bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCValue &Val,
+bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val,
const MCSymbol &Sym,
unsigned Type) const {
// If it's a compound relocation for N64 then we need the relocation if any
// sub-relocation needs it.
if (!isUInt<8>(Type))
- return needsRelocateWithSymbol(Val, Sym, Type & 0xff) ||
- needsRelocateWithSymbol(Val, Sym, (Type >> 8) & 0xff) ||
- needsRelocateWithSymbol(Val, Sym, (Type >> 16) & 0xff);
+ return needsRelocateWithSymbol(Asm, Val, Sym, Type & 0xff) ||
+ needsRelocateWithSymbol(Asm, Val, Sym, (Type >> 8) & 0xff) ||
+ needsRelocateWithSymbol(Asm, Val, Sym, (Type >> 16) & 0xff);
switch (Type) {
default:
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
index e58c361db3104..84204f389123b 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
@@ -28,7 +28,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
}
@@ -488,7 +489,8 @@ unsigned PPCELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return Type;
}
-bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &Sym,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
index 35e75489794f7..01953c4247235 100644
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
@@ -27,7 +27,8 @@ class RISCVELFObjectWriter : public MCELFObjectTargetWriter {
// Return true if the given relocation must be with a symbol rather than
// section plus offset.
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override {
// TODO: this is very conservative, update once RISC-V psABI requirements
// are clarified.
diff --git a/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp b/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
index f95e5ac1664e6..560423210dfa2 100644
--- a/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
+++ b/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
@@ -33,7 +33,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
}
@@ -144,7 +145,8 @@ unsigned SparcELFObjectWriter::getRelocType(MCContext &Ctx,
return ELF::R_SPARC_NONE;
}
-bool SparcELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool SparcELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
index ea9d42080b9ec..28d98ffc5c0e3 100644
--- a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
+++ b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
@@ -34,7 +34,8 @@ class SystemZELFObjectWriter : public MCELFObjectTargetWriter {
// Override MCELFObjectTargetWriter.
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -215,7 +216,8 @@ unsigned SystemZELFObjectWriter::getRelocType(MCContext &Ctx,
}
}
-bool SystemZELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool SystemZELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &Sym,
unsigned Type) const {
switch (V.getSpecifier()) {
diff --git a/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp b/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
index 5d0d18d86d3f8..71f1f85552536 100644
--- a/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
+++ b/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
@@ -32,7 +32,8 @@ class VEELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
} // namespace
@@ -146,7 +147,8 @@ unsigned VEELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return ELF::R_VE_NONE;
}
-bool VEELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool VEELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
index cac4b81429b00..537536619d148 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
@@ -11,6 +11,7 @@
#include "MCTargetDesc/X86MCTargetDesc.h"
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCExpr.h"
@@ -33,7 +34,8 @@ class X86ELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -386,7 +388,8 @@ unsigned X86ELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return getRelocType32(Ctx, Fixup.getLoc(), Specifier, RelType, IsPCRel, Kind);
}
-bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &Sym,
unsigned Type) const {
switch (V.getSpecifier()) {
@@ -396,7 +399,8 @@ bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
case X86MCExpr::VK_GOTPCREL_NORELAX:
return true;
default:
- return false;
+ return Type == ELF::R_X86_64_PLT32 &&
+ (Asm.getFragmentOffset(*Sym.getFragment()) + Sym.getOffset()) != 0;
}
}
diff --git a/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp b/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
index 7472371932f11..635cfa206bc1f 100644
--- a/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
+++ b/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
@@ -32,7 +32,8 @@ class XtensaObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
} // namespace
@@ -60,7 +61,8 @@ llvm::createXtensaObjectWriter(uint8_t OSABI, bool IsLittleEndian) {
return std::make_unique<XtensaObjectWriter>(OSABI);
}
-bool XtensaObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool XtensaObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
return false;
diff --git a/llvm/test/MC/ELF/plt-temporary.s b/llvm/test/MC/ELF/plt-temporary.s
new file mode 100644
index 0000000000000..9749bbdfe8134
--- /dev/null
+++ b/llvm/test/MC/ELF/plt-temporary.s
@@ -0,0 +1,14 @@
+// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | llvm-readobj -r - | FileCheck %s
+
+// Test that this produces a R_X86_64_PLT32 pointing to .Lfoo
+// instead of the section symbol.
+
+.section .text.a,"ax",@progbits
+jmp .Lfoo
+
+.text
+ret
+.Lfoo:
+ret
+
+// CHECK: R_X86_64_PLT32 .Lfoo 0xFFFFFFFFFFFFFFFC
|
|
@llvm/pr-subscribers-backend-arm Author: Peter Collingbourne (pcc) ChangesIn the following case: .section .text.a,"ax",@progbits .text we previously emitted an R_X86_64_PLT32 relocation for the jmp Full diff: https://github.com/llvm/llvm-project/pull/138795.diff 17 Files Affected:
diff --git a/llvm/include/llvm/MC/MCELFObjectWriter.h b/llvm/include/llvm/MC/MCELFObjectWriter.h
index f0f2dca4738e4..76a5ec6346770 100644
--- a/llvm/include/llvm/MC/MCELFObjectWriter.h
+++ b/llvm/include/llvm/MC/MCELFObjectWriter.h
@@ -88,7 +88,8 @@ class MCELFObjectTargetWriter : public MCObjectTargetWriter {
virtual unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const = 0;
- virtual bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ virtual bool needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val, const MCSymbol &Sym,
unsigned Type) const;
virtual void sortRelocs(const MCAssembler &Asm,
diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index 5c39daef9c98d..264a56f0966eb 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -1303,7 +1303,7 @@ bool ELFObjectWriter::useSectionSymbol(const MCAssembler &Asm,
if (Asm.isThumbFunc(Sym))
return false;
- return !TargetObjectWriter->needsRelocateWithSymbol(Val, *Sym, Type);
+ return !TargetObjectWriter->needsRelocateWithSymbol(Asm, Val, *Sym, Type);
}
bool ELFObjectWriter::checkRelocation(MCContext &Ctx, SMLoc Loc,
diff --git a/llvm/lib/MC/MCELFObjectTargetWriter.cpp b/llvm/lib/MC/MCELFObjectTargetWriter.cpp
index 49cca57d3aaa3..5cfac5ba093e7 100644
--- a/llvm/lib/MC/MCELFObjectTargetWriter.cpp
+++ b/llvm/lib/MC/MCELFObjectTargetWriter.cpp
@@ -17,7 +17,8 @@ MCELFObjectTargetWriter::MCELFObjectTargetWriter(bool Is64Bit_, uint8_t OSABI_,
: OSABI(OSABI_), ABIVersion(ABIVersion_), EMachine(EMachine_),
HasRelocationAddend(HasRelocationAddend_), Is64Bit(Is64Bit_) {}
-bool MCELFObjectTargetWriter::needsRelocateWithSymbol(const MCValue &,
+bool MCELFObjectTargetWriter::needsRelocateWithSymbol(const MCAssembler &,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
return false;
diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
index 53acf7dd61054..20d63415e768e 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
@@ -38,7 +38,8 @@ class AArch64ELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
bool IsILP32;
};
@@ -534,7 +535,8 @@ unsigned AArch64ELFObjectWriter::getRelocType(MCContext &Ctx,
llvm_unreachable("Unimplemented fixup -> relocation");
}
-bool AArch64ELFObjectWriter::needsRelocateWithSymbol(const MCValue &Val,
+bool AArch64ELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val,
const MCSymbol &,
unsigned) const {
// For memory-tagged symbols, ensure that the relocation uses the symbol. For
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
index 9fb681611594a..0dd71d55616ef 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
@@ -39,7 +39,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -50,7 +51,8 @@ ARMELFObjectWriter::ARMELFObjectWriter(uint8_t OSABI)
ELF::EM_ARM,
/*HasRelocationAddend*/ false) {}
-bool ARMELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool ARMELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
// FIXME: This is extremely conservative. This really needs to use an
diff --git a/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp b/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
index d424399ce6bc9..89df9d1b6bdce 100644
--- a/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
+++ b/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
@@ -29,7 +29,8 @@ class CSKYELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -167,7 +168,8 @@ unsigned CSKYELFObjectWriter::getRelocType(MCContext &Ctx,
}
}
-bool CSKYELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool CSKYELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &,
unsigned Type) const {
switch (V.getSpecifier()) {
diff --git a/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp b/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
index a21518e44116e..744c4427fbec6 100644
--- a/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
+++ b/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
@@ -26,7 +26,8 @@ class LanaiELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -72,7 +73,8 @@ unsigned LanaiELFObjectWriter::getRelocType(MCContext & /*Ctx*/,
return Type;
}
-bool LanaiELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool LanaiELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
index 5b6ecc1e8bc1f..55e9eef6de94e 100644
--- a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
+++ b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
@@ -26,7 +26,8 @@ class LoongArchELFObjectWriter : public MCELFObjectTargetWriter {
~LoongArchELFObjectWriter() override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override {
return EnableRelax;
}
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index 83073e4243414..acee6413a5651 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -50,7 +50,8 @@ class MipsELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
void sortRelocs(const MCAssembler &Asm,
std::vector<ELFRelocationEntry> &Relocs) override;
@@ -444,15 +445,16 @@ void MipsELFObjectWriter::sortRelocs(const MCAssembler &Asm,
Relocs[CopyTo++] = R.R;
}
-bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCValue &Val,
+bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val,
const MCSymbol &Sym,
unsigned Type) const {
// If it's a compound relocation for N64 then we need the relocation if any
// sub-relocation needs it.
if (!isUInt<8>(Type))
- return needsRelocateWithSymbol(Val, Sym, Type & 0xff) ||
- needsRelocateWithSymbol(Val, Sym, (Type >> 8) & 0xff) ||
- needsRelocateWithSymbol(Val, Sym, (Type >> 16) & 0xff);
+ return needsRelocateWithSymbol(Asm, Val, Sym, Type & 0xff) ||
+ needsRelocateWithSymbol(Asm, Val, Sym, (Type >> 8) & 0xff) ||
+ needsRelocateWithSymbol(Asm, Val, Sym, (Type >> 16) & 0xff);
switch (Type) {
default:
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
index e58c361db3104..84204f389123b 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
@@ -28,7 +28,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
}
@@ -488,7 +489,8 @@ unsigned PPCELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return Type;
}
-bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &Sym,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
index 35e75489794f7..01953c4247235 100644
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
@@ -27,7 +27,8 @@ class RISCVELFObjectWriter : public MCELFObjectTargetWriter {
// Return true if the given relocation must be with a symbol rather than
// section plus offset.
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override {
// TODO: this is very conservative, update once RISC-V psABI requirements
// are clarified.
diff --git a/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp b/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
index f95e5ac1664e6..560423210dfa2 100644
--- a/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
+++ b/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
@@ -33,7 +33,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
}
@@ -144,7 +145,8 @@ unsigned SparcELFObjectWriter::getRelocType(MCContext &Ctx,
return ELF::R_SPARC_NONE;
}
-bool SparcELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool SparcELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
index ea9d42080b9ec..28d98ffc5c0e3 100644
--- a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
+++ b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
@@ -34,7 +34,8 @@ class SystemZELFObjectWriter : public MCELFObjectTargetWriter {
// Override MCELFObjectTargetWriter.
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -215,7 +216,8 @@ unsigned SystemZELFObjectWriter::getRelocType(MCContext &Ctx,
}
}
-bool SystemZELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool SystemZELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &Sym,
unsigned Type) const {
switch (V.getSpecifier()) {
diff --git a/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp b/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
index 5d0d18d86d3f8..71f1f85552536 100644
--- a/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
+++ b/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
@@ -32,7 +32,8 @@ class VEELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
} // namespace
@@ -146,7 +147,8 @@ unsigned VEELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return ELF::R_VE_NONE;
}
-bool VEELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool VEELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
index cac4b81429b00..537536619d148 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
@@ -11,6 +11,7 @@
#include "MCTargetDesc/X86MCTargetDesc.h"
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCExpr.h"
@@ -33,7 +34,8 @@ class X86ELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -386,7 +388,8 @@ unsigned X86ELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return getRelocType32(Ctx, Fixup.getLoc(), Specifier, RelType, IsPCRel, Kind);
}
-bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &Sym,
unsigned Type) const {
switch (V.getSpecifier()) {
@@ -396,7 +399,8 @@ bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
case X86MCExpr::VK_GOTPCREL_NORELAX:
return true;
default:
- return false;
+ return Type == ELF::R_X86_64_PLT32 &&
+ (Asm.getFragmentOffset(*Sym.getFragment()) + Sym.getOffset()) != 0;
}
}
diff --git a/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp b/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
index 7472371932f11..635cfa206bc1f 100644
--- a/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
+++ b/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
@@ -32,7 +32,8 @@ class XtensaObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
} // namespace
@@ -60,7 +61,8 @@ llvm::createXtensaObjectWriter(uint8_t OSABI, bool IsLittleEndian) {
return std::make_unique<XtensaObjectWriter>(OSABI);
}
-bool XtensaObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool XtensaObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
return false;
diff --git a/llvm/test/MC/ELF/plt-temporary.s b/llvm/test/MC/ELF/plt-temporary.s
new file mode 100644
index 0000000000000..9749bbdfe8134
--- /dev/null
+++ b/llvm/test/MC/ELF/plt-temporary.s
@@ -0,0 +1,14 @@
+// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | llvm-readobj -r - | FileCheck %s
+
+// Test that this produces a R_X86_64_PLT32 pointing to .Lfoo
+// instead of the section symbol.
+
+.section .text.a,"ax",@progbits
+jmp .Lfoo
+
+.text
+ret
+.Lfoo:
+ret
+
+// CHECK: R_X86_64_PLT32 .Lfoo 0xFFFFFFFFFFFFFFFC
|
|
@llvm/pr-subscribers-backend-xtensa Author: Peter Collingbourne (pcc) ChangesIn the following case: .section .text.a,"ax",@progbits .text we previously emitted an R_X86_64_PLT32 relocation for the jmp Full diff: https://github.com/llvm/llvm-project/pull/138795.diff 17 Files Affected:
diff --git a/llvm/include/llvm/MC/MCELFObjectWriter.h b/llvm/include/llvm/MC/MCELFObjectWriter.h
index f0f2dca4738e4..76a5ec6346770 100644
--- a/llvm/include/llvm/MC/MCELFObjectWriter.h
+++ b/llvm/include/llvm/MC/MCELFObjectWriter.h
@@ -88,7 +88,8 @@ class MCELFObjectTargetWriter : public MCObjectTargetWriter {
virtual unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const = 0;
- virtual bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ virtual bool needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val, const MCSymbol &Sym,
unsigned Type) const;
virtual void sortRelocs(const MCAssembler &Asm,
diff --git a/llvm/lib/MC/ELFObjectWriter.cpp b/llvm/lib/MC/ELFObjectWriter.cpp
index 5c39daef9c98d..264a56f0966eb 100644
--- a/llvm/lib/MC/ELFObjectWriter.cpp
+++ b/llvm/lib/MC/ELFObjectWriter.cpp
@@ -1303,7 +1303,7 @@ bool ELFObjectWriter::useSectionSymbol(const MCAssembler &Asm,
if (Asm.isThumbFunc(Sym))
return false;
- return !TargetObjectWriter->needsRelocateWithSymbol(Val, *Sym, Type);
+ return !TargetObjectWriter->needsRelocateWithSymbol(Asm, Val, *Sym, Type);
}
bool ELFObjectWriter::checkRelocation(MCContext &Ctx, SMLoc Loc,
diff --git a/llvm/lib/MC/MCELFObjectTargetWriter.cpp b/llvm/lib/MC/MCELFObjectTargetWriter.cpp
index 49cca57d3aaa3..5cfac5ba093e7 100644
--- a/llvm/lib/MC/MCELFObjectTargetWriter.cpp
+++ b/llvm/lib/MC/MCELFObjectTargetWriter.cpp
@@ -17,7 +17,8 @@ MCELFObjectTargetWriter::MCELFObjectTargetWriter(bool Is64Bit_, uint8_t OSABI_,
: OSABI(OSABI_), ABIVersion(ABIVersion_), EMachine(EMachine_),
HasRelocationAddend(HasRelocationAddend_), Is64Bit(Is64Bit_) {}
-bool MCELFObjectTargetWriter::needsRelocateWithSymbol(const MCValue &,
+bool MCELFObjectTargetWriter::needsRelocateWithSymbol(const MCAssembler &,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
return false;
diff --git a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
index 53acf7dd61054..20d63415e768e 100644
--- a/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
+++ b/llvm/lib/Target/AArch64/MCTargetDesc/AArch64ELFObjectWriter.cpp
@@ -38,7 +38,8 @@ class AArch64ELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
bool IsILP32;
};
@@ -534,7 +535,8 @@ unsigned AArch64ELFObjectWriter::getRelocType(MCContext &Ctx,
llvm_unreachable("Unimplemented fixup -> relocation");
}
-bool AArch64ELFObjectWriter::needsRelocateWithSymbol(const MCValue &Val,
+bool AArch64ELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val,
const MCSymbol &,
unsigned) const {
// For memory-tagged symbols, ensure that the relocation uses the symbol. For
diff --git a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
index 9fb681611594a..0dd71d55616ef 100644
--- a/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
+++ b/llvm/lib/Target/ARM/MCTargetDesc/ARMELFObjectWriter.cpp
@@ -39,7 +39,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -50,7 +51,8 @@ ARMELFObjectWriter::ARMELFObjectWriter(uint8_t OSABI)
ELF::EM_ARM,
/*HasRelocationAddend*/ false) {}
-bool ARMELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool ARMELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
// FIXME: This is extremely conservative. This really needs to use an
diff --git a/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp b/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
index d424399ce6bc9..89df9d1b6bdce 100644
--- a/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
+++ b/llvm/lib/Target/CSKY/MCTargetDesc/CSKYELFObjectWriter.cpp
@@ -29,7 +29,8 @@ class CSKYELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -167,7 +168,8 @@ unsigned CSKYELFObjectWriter::getRelocType(MCContext &Ctx,
}
}
-bool CSKYELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool CSKYELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &,
unsigned Type) const {
switch (V.getSpecifier()) {
diff --git a/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp b/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
index a21518e44116e..744c4427fbec6 100644
--- a/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
+++ b/llvm/lib/Target/Lanai/MCTargetDesc/LanaiELFObjectWriter.cpp
@@ -26,7 +26,8 @@ class LanaiELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -72,7 +73,8 @@ unsigned LanaiELFObjectWriter::getRelocType(MCContext & /*Ctx*/,
return Type;
}
-bool LanaiELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool LanaiELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
index 5b6ecc1e8bc1f..55e9eef6de94e 100644
--- a/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
+++ b/llvm/lib/Target/LoongArch/MCTargetDesc/LoongArchELFObjectWriter.cpp
@@ -26,7 +26,8 @@ class LoongArchELFObjectWriter : public MCELFObjectTargetWriter {
~LoongArchELFObjectWriter() override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override {
return EnableRelax;
}
diff --git a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
index 83073e4243414..acee6413a5651 100644
--- a/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
+++ b/llvm/lib/Target/Mips/MCTargetDesc/MipsELFObjectWriter.cpp
@@ -50,7 +50,8 @@ class MipsELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
void sortRelocs(const MCAssembler &Asm,
std::vector<ELFRelocationEntry> &Relocs) override;
@@ -444,15 +445,16 @@ void MipsELFObjectWriter::sortRelocs(const MCAssembler &Asm,
Relocs[CopyTo++] = R.R;
}
-bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCValue &Val,
+bool MipsELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &Val,
const MCSymbol &Sym,
unsigned Type) const {
// If it's a compound relocation for N64 then we need the relocation if any
// sub-relocation needs it.
if (!isUInt<8>(Type))
- return needsRelocateWithSymbol(Val, Sym, Type & 0xff) ||
- needsRelocateWithSymbol(Val, Sym, (Type >> 8) & 0xff) ||
- needsRelocateWithSymbol(Val, Sym, (Type >> 16) & 0xff);
+ return needsRelocateWithSymbol(Asm, Val, Sym, Type & 0xff) ||
+ needsRelocateWithSymbol(Asm, Val, Sym, (Type >> 8) & 0xff) ||
+ needsRelocateWithSymbol(Asm, Val, Sym, (Type >> 16) & 0xff);
switch (Type) {
default:
diff --git a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
index e58c361db3104..84204f389123b 100644
--- a/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
+++ b/llvm/lib/Target/PowerPC/MCTargetDesc/PPCELFObjectWriter.cpp
@@ -28,7 +28,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
}
@@ -488,7 +489,8 @@ unsigned PPCELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return Type;
}
-bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool PPCELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &Sym,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
index 35e75489794f7..01953c4247235 100644
--- a/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
+++ b/llvm/lib/Target/RISCV/MCTargetDesc/RISCVELFObjectWriter.cpp
@@ -27,7 +27,8 @@ class RISCVELFObjectWriter : public MCELFObjectTargetWriter {
// Return true if the given relocation must be with a symbol rather than
// section plus offset.
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override {
// TODO: this is very conservative, update once RISC-V psABI requirements
// are clarified.
diff --git a/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp b/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
index f95e5ac1664e6..560423210dfa2 100644
--- a/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
+++ b/llvm/lib/Target/Sparc/MCTargetDesc/SparcELFObjectWriter.cpp
@@ -33,7 +33,8 @@ namespace {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
}
@@ -144,7 +145,8 @@ unsigned SparcELFObjectWriter::getRelocType(MCContext &Ctx,
return ELF::R_SPARC_NONE;
}
-bool SparcELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool SparcELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
index ea9d42080b9ec..28d98ffc5c0e3 100644
--- a/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
+++ b/llvm/lib/Target/SystemZ/MCTargetDesc/SystemZELFObjectWriter.cpp
@@ -34,7 +34,8 @@ class SystemZELFObjectWriter : public MCELFObjectTargetWriter {
// Override MCELFObjectTargetWriter.
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -215,7 +216,8 @@ unsigned SystemZELFObjectWriter::getRelocType(MCContext &Ctx,
}
}
-bool SystemZELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool SystemZELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &Sym,
unsigned Type) const {
switch (V.getSpecifier()) {
diff --git a/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp b/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
index 5d0d18d86d3f8..71f1f85552536 100644
--- a/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
+++ b/llvm/lib/Target/VE/MCTargetDesc/VEELFObjectWriter.cpp
@@ -32,7 +32,8 @@ class VEELFObjectWriter : public MCELFObjectTargetWriter {
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
} // namespace
@@ -146,7 +147,8 @@ unsigned VEELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return ELF::R_VE_NONE;
}
-bool VEELFObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool VEELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
switch (Type) {
diff --git a/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
index cac4b81429b00..537536619d148 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86ELFObjectWriter.cpp
@@ -11,6 +11,7 @@
#include "MCTargetDesc/X86MCTargetDesc.h"
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCAssembler.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCELFObjectWriter.h"
#include "llvm/MC/MCExpr.h"
@@ -33,7 +34,8 @@ class X86ELFObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
@@ -386,7 +388,8 @@ unsigned X86ELFObjectWriter::getRelocType(MCContext &Ctx, const MCValue &Target,
return getRelocType32(Ctx, Fixup.getLoc(), Specifier, RelType, IsPCRel, Kind);
}
-bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
+bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &V,
const MCSymbol &Sym,
unsigned Type) const {
switch (V.getSpecifier()) {
@@ -396,7 +399,8 @@ bool X86ELFObjectWriter::needsRelocateWithSymbol(const MCValue &V,
case X86MCExpr::VK_GOTPCREL_NORELAX:
return true;
default:
- return false;
+ return Type == ELF::R_X86_64_PLT32 &&
+ (Asm.getFragmentOffset(*Sym.getFragment()) + Sym.getOffset()) != 0;
}
}
diff --git a/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp b/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
index 7472371932f11..635cfa206bc1f 100644
--- a/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
+++ b/llvm/lib/Target/Xtensa/MCTargetDesc/XtensaELFObjectWriter.cpp
@@ -32,7 +32,8 @@ class XtensaObjectWriter : public MCELFObjectTargetWriter {
protected:
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
const MCFixup &Fixup, bool IsPCRel) const override;
- bool needsRelocateWithSymbol(const MCValue &Val, const MCSymbol &Sym,
+ bool needsRelocateWithSymbol(const MCAssembler &Asm, const MCValue &Val,
+ const MCSymbol &Sym,
unsigned Type) const override;
};
} // namespace
@@ -60,7 +61,8 @@ llvm::createXtensaObjectWriter(uint8_t OSABI, bool IsLittleEndian) {
return std::make_unique<XtensaObjectWriter>(OSABI);
}
-bool XtensaObjectWriter::needsRelocateWithSymbol(const MCValue &,
+bool XtensaObjectWriter::needsRelocateWithSymbol(const MCAssembler &Asm,
+ const MCValue &,
const MCSymbol &,
unsigned Type) const {
return false;
diff --git a/llvm/test/MC/ELF/plt-temporary.s b/llvm/test/MC/ELF/plt-temporary.s
new file mode 100644
index 0000000000000..9749bbdfe8134
--- /dev/null
+++ b/llvm/test/MC/ELF/plt-temporary.s
@@ -0,0 +1,14 @@
+// RUN: llvm-mc -filetype=obj -triple x86_64-pc-linux-gnu %s -o - | llvm-readobj -r - | FileCheck %s
+
+// Test that this produces a R_X86_64_PLT32 pointing to .Lfoo
+// instead of the section symbol.
+
+.section .text.a,"ax",@progbits
+jmp .Lfoo
+
+.text
+ret
+.Lfoo:
+ret
+
+// CHECK: R_X86_64_PLT32 .Lfoo 0xFFFFFFFFFFFFFFFC
|
This was referenced May 7, 2025
Why is it invalid? Can you elaborate the scenario when a PLT is placed at the jmp target? |
|
I was thinking something like a range extension thunk (although those don't currently exist on x86), which could be useful for something like a medium code model that supports >2GB code. In that case, if your branch and target are on opposite ends of the output file which is possible e.g. if they are in different sections you would need a thunk. The reason I wanted to fix this is that having these relocations breaks the branch-to-branch optimization as noted in #138366 (comment) . |
|
I've read #138366 (comment) but I am still not following. Note that range extension thunks track both the symbol and the addend (e.g. https://reviews.llvm.org/D70637 (AArch64)). |
|
With relative vtables we have This becomes a PLT32 pointing to foo with addend 0. This should not be treated as a branch to foo+4 if a PLT/thunk is needed. We can also have With the current implementation that creates a PLT32 with addend 0 for branching to .text+4 this is not distinguishable from the relative vtable case except via SHF_EXECINSTR or STT_SECTION on the target symbol. Since we generally want relocation processing to be independent of this kind of context, I think the right way to reconcile these two cases is that a PLT32 can only be treated as a reference to the symbol itself. GNU as already does this and this change makes MC do the same. |
|
The goal is to differentiate two scenarios when a symbol is referenced by a potential R_X86_64_PLT32 relocation:
When (See https://sourceware.org/bugzilla/show_bug.cgi?id=26263 for gas behavior. I do not follow the argument "Since PLT32 relocation must be against symbols". I don't know whether it fixed an issue in GNU ld's i386 port for the 32-bit case.) I am still confused as to what issues this PR attempts to resolve. Current behavior: This PR changes If we implement range extension thunks, we should support both PC32 and PLT32. |
|
Sorry, let me try again with the concrete problem that I was seeing and trying to solve. With this .s file: and with an lld patched with #138366: The instruction at 0x201126 is incorrect. This is because of the interpretation of After #138795 we have: The alternative fix, which I think I'm now leaning towards, would be to change how the branch-to-branch optimization handles relocations to STT_SECTION symbols. A relocation pointing to the STT_SECTION for .text with addend 1 would be treated as a branch to |
Thanks for the explanation. I haven't read through the lld branch-to-branch optimization patch. However, I agree that adding a special case for STT_SECTION to the linker might be the right solution. Changing the assembler regarding PLT32 looks fishy. I find the GNU Assembler change strange. I believe it should only apply to i386 (if we ever decide to dance with PLT32/PC32)
|
|
Abandoning this and will address in the linker change (#138366) instead. |
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In the following case:
.section .text.a,"ax",@progbits
jmp .Lfoo
.text
ret
.Lfoo:
ret
we previously emitted an R_X86_64_PLT32 relocation for the jmp
instruction pointing to the .text section symbol with an addend of
-3. This is invalid because the linker is technically allowed to place
a PLT or other thunk at the jmp target, resulting in an invalid branch
to the thunk address + 1. Fix that by forcing a symbol to be used if it
has a non-zero value.