From 03c7f3a2d0b5c38c1156e40f40808a393b4627c6 Mon Sep 17 00:00:00 2001 From: Rui Ueyama Date: Sat, 17 Feb 2018 20:28:15 +0000 Subject: [PATCH] Factor out common code from applySecRel functions. Differential Revision: https://reviews.llvm.org/D43412 llvm-svn: 325444 --- lld/COFF/Chunks.cpp | 53 +++++++++++++++++++++++++-------------------- 1 file changed, 29 insertions(+), 24 deletions(-) diff --git a/lld/COFF/Chunks.cpp b/lld/COFF/Chunks.cpp index cd0b1383fe9c..1d2c5d9aef93 100644 --- a/lld/COFF/Chunks.cpp +++ b/lld/COFF/Chunks.cpp @@ -51,13 +51,21 @@ static void add64(uint8_t *P, int64_t V) { write64le(P, read64le(P) + V); } static void or16(uint8_t *P, uint16_t V) { write16le(P, read16le(P) | V); } static void or32(uint8_t *P, uint32_t V) { write32le(P, read32le(P) | V); } +// Verify that given sections are appropriate targets for SECREL +// relocations. This check is relaxed because unfortunately debug +// sections have section-relative relocations against absolute symbols. +static bool checkSecRel(const SectionChunk *Sec, OutputSection *OS) { + if (OS) + return true; + if (Sec->isCodeView()) + return false; + fatal("SECREL relocation cannot be applied to absolute symbols"); +} + static void applySecRel(const SectionChunk *Sec, uint8_t *Off, OutputSection *OS, uint64_t S) { - if (!OS) { - if (Sec->isCodeView()) - return; - fatal("SECREL relocation cannot be applied to absolute symbols"); - } + if (!checkSecRel(Sec, OS)) + return; uint64_t SecRel = S - OS->getRVA(); if (SecRel > UINT32_MAX) { error("overflow in SECREL relocation in section: " + Sec->getSectionName()); @@ -213,16 +221,18 @@ static void applyArm64Ldr(uint8_t *Off, uint64_t Imm) { applyArm64Imm(Off, Imm >> Size, Size); } -static void applySecRelAdd(const SectionChunk *Sec, uint8_t *Off, - OutputSection *OS, uint64_t S, int Shift) { - if (!OS) { - if (Sec->isCodeView()) - return; - fatal("SECREL relocation cannot be applied to absolute symbols"); - } - uint64_t SecRel = S - OS->getRVA(); - SecRel >>= Shift; - if (Shift > 0 && SecRel > 0xfff) { +static void applySecRelLow12A(const SectionChunk *Sec, uint8_t *Off, + OutputSection *OS, uint64_t S) { + if (checkSecRel(Sec, OS)) + applyArm64Imm(Off, (S - OS->getRVA()) & 0xfff, 0); +} + +static void applySecRelHigh12A(const SectionChunk *Sec, uint8_t *Off, + OutputSection *OS, uint64_t S) { + if (!checkSecRel(Sec, OS)) + return; + uint64_t SecRel = (S - OS->getRVA()) >> 12; + if (0xfff < SecRel) { error("overflow in SECREL_HIGH12A relocation in section: " + Sec->getSectionName()); return; @@ -232,13 +242,8 @@ static void applySecRelAdd(const SectionChunk *Sec, uint8_t *Off, static void applySecRelLdr(const SectionChunk *Sec, uint8_t *Off, OutputSection *OS, uint64_t S) { - if (!OS) { - if (Sec->isCodeView()) - return; - fatal("SECREL relocation cannot be applied to absolute symbols"); - } - uint64_t SecRel = S - OS->getRVA(); - applyArm64Ldr(Off, SecRel & 0xfff); + if (checkSecRel(Sec, OS)) + applyArm64Ldr(Off, (S - OS->getRVA()) & 0xfff); } void SectionChunk::applyRelARM64(uint8_t *Off, uint16_t Type, OutputSection *OS, @@ -252,8 +257,8 @@ void SectionChunk::applyRelARM64(uint8_t *Off, uint16_t Type, OutputSection *OS, case IMAGE_REL_ARM64_ADDR32NB: add32(Off, S); break; case IMAGE_REL_ARM64_ADDR64: add64(Off, S + Config->ImageBase); break; case IMAGE_REL_ARM64_SECREL: applySecRel(this, Off, OS, S); break; - case IMAGE_REL_ARM64_SECREL_LOW12A: applySecRelAdd(this, Off, OS, S, 0); break; - case IMAGE_REL_ARM64_SECREL_HIGH12A: applySecRelAdd(this, Off, OS, S, 12); break; + case IMAGE_REL_ARM64_SECREL_LOW12A: applySecRelLow12A(this, Off, OS, S); break; + case IMAGE_REL_ARM64_SECREL_HIGH12A: applySecRelHigh12A(this, Off, OS, S); break; case IMAGE_REL_ARM64_SECREL_LOW12L: applySecRelLdr(this, Off, OS, S); break; default: fatal("unsupported relocation type 0x" + Twine::utohexstr(Type));