mirror of
https://github.com/Gericom/teak-llvm.git
synced 2025-06-26 06:48:51 -04:00
5af037f1e9
Linker relaxation may change code size. We need to fix up the alignment of alignment directive in text section by inserting Nops and R_RISCV_ALIGN relocation type. So then linker could satisfy the alignment by removing Nops. To do this: 1. Add shouldInsertExtraNopBytesForCodeAlign target hook to calculate the Nops we need to insert. 2. Add shouldInsertFixupForCodeAlign target hook to insert R_RISCV_ALIGN fixup type. Differential Revision: https://reviews.llvm.org/D47755 llvm-svn: 352616
107 lines
3.4 KiB
C++
107 lines
3.4 KiB
C++
//===-- RISCVELFObjectWriter.cpp - RISCV ELF Writer -----------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "MCTargetDesc/RISCVFixupKinds.h"
|
|
#include "MCTargetDesc/RISCVMCTargetDesc.h"
|
|
#include "llvm/MC/MCELFObjectWriter.h"
|
|
#include "llvm/MC/MCFixup.h"
|
|
#include "llvm/MC/MCObjectWriter.h"
|
|
#include "llvm/Support/ErrorHandling.h"
|
|
|
|
using namespace llvm;
|
|
|
|
namespace {
|
|
class RISCVELFObjectWriter : public MCELFObjectTargetWriter {
|
|
public:
|
|
RISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit);
|
|
|
|
~RISCVELFObjectWriter() override;
|
|
|
|
// Return true if the given relocation must be with a symbol rather than
|
|
// section plus offset.
|
|
bool needsRelocateWithSymbol(const MCSymbol &Sym,
|
|
unsigned Type) const override {
|
|
// TODO: this is very conservative, update once RISC-V psABI requirements
|
|
// are clarified.
|
|
return true;
|
|
}
|
|
|
|
protected:
|
|
unsigned getRelocType(MCContext &Ctx, const MCValue &Target,
|
|
const MCFixup &Fixup, bool IsPCRel) const override;
|
|
};
|
|
}
|
|
|
|
RISCVELFObjectWriter::RISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit)
|
|
: MCELFObjectTargetWriter(Is64Bit, OSABI, ELF::EM_RISCV,
|
|
/*HasRelocationAddend*/ true) {}
|
|
|
|
RISCVELFObjectWriter::~RISCVELFObjectWriter() {}
|
|
|
|
unsigned RISCVELFObjectWriter::getRelocType(MCContext &Ctx,
|
|
const MCValue &Target,
|
|
const MCFixup &Fixup,
|
|
bool IsPCRel) const {
|
|
// Determine the type of the relocation
|
|
switch ((unsigned)Fixup.getKind()) {
|
|
default:
|
|
llvm_unreachable("invalid fixup kind!");
|
|
case FK_Data_4:
|
|
return ELF::R_RISCV_32;
|
|
case FK_Data_8:
|
|
return ELF::R_RISCV_64;
|
|
case FK_Data_Add_1:
|
|
return ELF::R_RISCV_ADD8;
|
|
case FK_Data_Add_2:
|
|
return ELF::R_RISCV_ADD16;
|
|
case FK_Data_Add_4:
|
|
return ELF::R_RISCV_ADD32;
|
|
case FK_Data_Add_8:
|
|
return ELF::R_RISCV_ADD64;
|
|
case FK_Data_Sub_1:
|
|
return ELF::R_RISCV_SUB8;
|
|
case FK_Data_Sub_2:
|
|
return ELF::R_RISCV_SUB16;
|
|
case FK_Data_Sub_4:
|
|
return ELF::R_RISCV_SUB32;
|
|
case FK_Data_Sub_8:
|
|
return ELF::R_RISCV_SUB64;
|
|
case RISCV::fixup_riscv_hi20:
|
|
return ELF::R_RISCV_HI20;
|
|
case RISCV::fixup_riscv_lo12_i:
|
|
return ELF::R_RISCV_LO12_I;
|
|
case RISCV::fixup_riscv_lo12_s:
|
|
return ELF::R_RISCV_LO12_S;
|
|
case RISCV::fixup_riscv_pcrel_hi20:
|
|
return ELF::R_RISCV_PCREL_HI20;
|
|
case RISCV::fixup_riscv_pcrel_lo12_i:
|
|
return ELF::R_RISCV_PCREL_LO12_I;
|
|
case RISCV::fixup_riscv_pcrel_lo12_s:
|
|
return ELF::R_RISCV_PCREL_LO12_S;
|
|
case RISCV::fixup_riscv_jal:
|
|
return ELF::R_RISCV_JAL;
|
|
case RISCV::fixup_riscv_branch:
|
|
return ELF::R_RISCV_BRANCH;
|
|
case RISCV::fixup_riscv_rvc_jump:
|
|
return ELF::R_RISCV_RVC_JUMP;
|
|
case RISCV::fixup_riscv_rvc_branch:
|
|
return ELF::R_RISCV_RVC_BRANCH;
|
|
case RISCV::fixup_riscv_call:
|
|
return ELF::R_RISCV_CALL;
|
|
case RISCV::fixup_riscv_relax:
|
|
return ELF::R_RISCV_RELAX;
|
|
case RISCV::fixup_riscv_align:
|
|
return ELF::R_RISCV_ALIGN;
|
|
}
|
|
}
|
|
|
|
std::unique_ptr<MCObjectTargetWriter>
|
|
llvm::createRISCVELFObjectWriter(uint8_t OSABI, bool Is64Bit) {
|
|
return llvm::make_unique<RISCVELFObjectWriter>(OSABI, Is64Bit);
|
|
}
|