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Diffstat (limited to 'lld/ELF/ScriptParser.cpp')
-rw-r--r--lld/ELF/ScriptParser.cpp252
1 files changed, 173 insertions, 79 deletions
diff --git a/lld/ELF/ScriptParser.cpp b/lld/ELF/ScriptParser.cpp
index 7331d1156f27..4d73541b3d42 100644
--- a/lld/ELF/ScriptParser.cpp
+++ b/lld/ELF/ScriptParser.cpp
@@ -14,10 +14,11 @@
#include "ScriptParser.h"
#include "Config.h"
#include "Driver.h"
-#include "InputSection.h"
+#include "InputFiles.h"
#include "LinkerScript.h"
#include "OutputSections.h"
#include "ScriptLexer.h"
+#include "SymbolTable.h"
#include "Symbols.h"
#include "Target.h"
#include "lld/Common/CommonLinkerContext.h"
@@ -31,7 +32,7 @@
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Path.h"
-#include "llvm/Support/ScopedPrinter.h"
+#include "llvm/Support/SaveAndRestore.h"
#include "llvm/Support/TimeProfiler.h"
#include <cassert>
#include <limits>
@@ -91,8 +92,8 @@ private:
std::array<uint8_t, 4> readFill();
bool readSectionDirective(OutputSection *cmd, StringRef tok1, StringRef tok2);
void readSectionAddressType(OutputSection *cmd);
- OutputSection *readOverlaySectionDescription();
- OutputSection *readOutputSectionDescription(StringRef outSec);
+ OutputDesc *readOverlaySectionDescription();
+ OutputDesc *readOutputSectionDescription(StringRef outSec);
SmallVector<SectionCommand *, 0> readOverlay();
SmallVector<StringRef, 0> readOutputSectionPhdrs();
std::pair<uint64_t, uint64_t> readInputSectionFlags();
@@ -135,6 +136,9 @@ private:
// True if a script being read is in the --sysroot directory.
bool isUnderSysroot = false;
+ bool seenDataAlign = false;
+ bool seenRelroEnd = false;
+
// A set to detect an INCLUDE() cycle.
StringSet<> seen;
};
@@ -348,7 +352,7 @@ void ScriptParser::readEntry() {
expect("(");
StringRef tok = next();
if (config->entry.empty())
- config->entry = tok;
+ config->entry = unquote(tok);
expect(")");
}
@@ -412,6 +416,7 @@ void ScriptParser::readOutputArch() {
static std::pair<ELFKind, uint16_t> parseBfdName(StringRef s) {
return StringSwitch<std::pair<ELFKind, uint16_t>>(s)
.Case("elf32-i386", {ELF32LEKind, EM_386})
+ .Case("elf32-avr", {ELF32LEKind, EM_AVR})
.Case("elf32-iamcu", {ELF32LEKind, EM_IAMCU})
.Case("elf32-littlearm", {ELF32LEKind, EM_ARM})
.Case("elf32-x86-64", {ELF32LEKind, EM_X86_64})
@@ -534,14 +539,14 @@ SmallVector<SectionCommand *, 0> ScriptParser::readOverlay() {
while (!errorCount() && !consume("}")) {
// VA is the same for all sections. The LMAs are consecutive in memory
// starting from the base load address specified.
- OutputSection *os = readOverlaySectionDescription();
- os->addrExpr = addrExpr;
+ OutputDesc *osd = readOverlaySectionDescription();
+ osd->osec.addrExpr = addrExpr;
if (prev)
- os->lmaExpr = [=] { return prev->getLMA() + prev->size; };
+ osd->osec.lmaExpr = [=] { return prev->getLMA() + prev->size; };
else
- os->lmaExpr = lmaExpr;
- v.push_back(os);
- prev = os;
+ osd->osec.lmaExpr = lmaExpr;
+ v.push_back(osd);
+ prev = &osd->osec;
}
// According to the specification, at the end of the overlay, the location
@@ -551,7 +556,7 @@ SmallVector<SectionCommand *, 0> ScriptParser::readOverlay() {
Expr moveDot = [=] {
uint64_t max = 0;
for (SectionCommand *cmd : v)
- max = std::max(max, cast<OutputSection>(cmd)->size);
+ max = std::max(max, cast<OutputDesc>(cmd)->osec.size);
return addrExpr().getValue() + max;
};
v.push_back(make<SymbolAssignment>(".", moveDot, getCurrentLocation()));
@@ -583,6 +588,14 @@ void ScriptParser::readSections() {
else
v.push_back(readOutputSectionDescription(tok));
}
+
+ // If DATA_SEGMENT_RELRO_END is absent, for sections after DATA_SEGMENT_ALIGN,
+ // the relro fields should be cleared.
+ if (!seenRelroEnd)
+ for (SectionCommand *cmd : v)
+ if (auto *osd = dyn_cast<OutputDesc>(cmd))
+ osd->osec.relro = false;
+
script->sectionCommands.insert(script->sectionCommands.end(), v.begin(),
v.end());
@@ -599,8 +612,8 @@ void ScriptParser::readSections() {
StringRef where = next();
SmallVector<StringRef, 0> names;
for (SectionCommand *cmd : v)
- if (auto *os = dyn_cast<OutputSection>(cmd))
- names.push_back(os->name);
+ if (auto *os = dyn_cast<OutputDesc>(cmd))
+ names.push_back(os->osec.name);
if (!names.empty())
script->insertCommands.push_back({std::move(names), isAfter, where});
}
@@ -611,7 +624,7 @@ void ScriptParser::readTarget() {
// for --format. We recognize only /^elf/ and "binary" in the linker
// script as well.
expect("(");
- StringRef tok = next();
+ StringRef tok = unquote(next());
expect(")");
if (tok.startswith("elf"))
@@ -624,14 +637,16 @@ void ScriptParser::readTarget() {
static int precedence(StringRef op) {
return StringSwitch<int>(op)
- .Cases("*", "/", "%", 8)
- .Cases("+", "-", 7)
- .Cases("<<", ">>", 6)
- .Cases("<", "<=", ">", ">=", "==", "!=", 5)
- .Case("&", 4)
- .Case("|", 3)
- .Case("&&", 2)
- .Case("||", 1)
+ .Cases("*", "/", "%", 10)
+ .Cases("+", "-", 9)
+ .Cases("<<", ">>", 8)
+ .Cases("<", "<=", ">", ">=", 7)
+ .Cases("==", "!=", 6)
+ .Case("&", 5)
+ .Case("|", 4)
+ .Case("&&", 3)
+ .Case("||", 2)
+ .Case("?", 1)
.Default(-1);
}
@@ -787,19 +802,45 @@ Expr ScriptParser::readAssert() {
};
}
+#define ECase(X) \
+ { #X, X }
+constexpr std::pair<const char *, unsigned> typeMap[] = {
+ ECase(SHT_PROGBITS), ECase(SHT_NOTE), ECase(SHT_NOBITS),
+ ECase(SHT_INIT_ARRAY), ECase(SHT_FINI_ARRAY), ECase(SHT_PREINIT_ARRAY),
+};
+#undef ECase
+
// Tries to read the special directive for an output section definition which
-// can be one of following: "(NOLOAD)", "(COPY)", "(INFO)" or "(OVERLAY)".
-// Tok1 and Tok2 are next 2 tokens peeked. See comment for readSectionAddressType below.
+// can be one of following: "(NOLOAD)", "(COPY)", "(INFO)", "(OVERLAY)", and
+// "(TYPE=<value>)".
+// Tok1 and Tok2 are next 2 tokens peeked. See comment for
+// readSectionAddressType below.
bool ScriptParser::readSectionDirective(OutputSection *cmd, StringRef tok1, StringRef tok2) {
if (tok1 != "(")
return false;
- if (tok2 != "NOLOAD" && tok2 != "COPY" && tok2 != "INFO" && tok2 != "OVERLAY")
+ if (tok2 != "NOLOAD" && tok2 != "COPY" && tok2 != "INFO" &&
+ tok2 != "OVERLAY" && tok2 != "TYPE")
return false;
expect("(");
if (consume("NOLOAD")) {
- cmd->noload = true;
cmd->type = SHT_NOBITS;
+ cmd->typeIsSet = true;
+ } else if (consume("TYPE")) {
+ expect("=");
+ StringRef value = peek();
+ auto it = llvm::find_if(typeMap, [=](auto e) { return e.first == value; });
+ if (it != std::end(typeMap)) {
+ // The value is a recognized literal SHT_*.
+ cmd->type = it->second;
+ skip();
+ } else if (value.startswith("SHT_")) {
+ setError("unknown section type " + value);
+ } else {
+ // Otherwise, read an expression.
+ cmd->type = readExpr()().getValue();
+ }
+ cmd->typeIsSet = true;
} else {
skip(); // This is "COPY", "INFO" or "OVERLAY".
cmd->nonAlloc = true;
@@ -820,7 +861,11 @@ bool ScriptParser::readSectionDirective(OutputSection *cmd, StringRef tok1, Stri
// https://sourceware.org/binutils/docs/ld/Output-Section-Address.html
// https://sourceware.org/binutils/docs/ld/Output-Section-Type.html
void ScriptParser::readSectionAddressType(OutputSection *cmd) {
- if (readSectionDirective(cmd, peek(), peek2()))
+ // Temporarily set inExpr to support TYPE=<value> without spaces.
+ bool saved = std::exchange(inExpr, true);
+ bool isDirective = readSectionDirective(cmd, peek(), peek2());
+ inExpr = saved;
+ if (isDirective)
return;
cmd->addrExpr = readExpr();
@@ -839,45 +884,46 @@ static Expr checkAlignment(Expr e, std::string &loc) {
};
}
-OutputSection *ScriptParser::readOverlaySectionDescription() {
- OutputSection *cmd =
- script->createOutputSection(next(), getCurrentLocation());
- cmd->inOverlay = true;
+OutputDesc *ScriptParser::readOverlaySectionDescription() {
+ OutputDesc *osd = script->createOutputSection(next(), getCurrentLocation());
+ osd->osec.inOverlay = true;
expect("{");
while (!errorCount() && !consume("}")) {
uint64_t withFlags = 0;
uint64_t withoutFlags = 0;
if (consume("INPUT_SECTION_FLAGS"))
std::tie(withFlags, withoutFlags) = readInputSectionFlags();
- cmd->commands.push_back(
+ osd->osec.commands.push_back(
readInputSectionRules(next(), withFlags, withoutFlags));
}
- return cmd;
+ return osd;
}
-OutputSection *ScriptParser::readOutputSectionDescription(StringRef outSec) {
- OutputSection *cmd =
- script->createOutputSection(outSec, getCurrentLocation());
+OutputDesc *ScriptParser::readOutputSectionDescription(StringRef outSec) {
+ OutputDesc *cmd = script->createOutputSection(outSec, getCurrentLocation());
+ OutputSection *osec = &cmd->osec;
+ // Maybe relro. Will reset to false if DATA_SEGMENT_RELRO_END is absent.
+ osec->relro = seenDataAlign && !seenRelroEnd;
size_t symbolsReferenced = script->referencedSymbols.size();
if (peek() != ":")
- readSectionAddressType(cmd);
+ readSectionAddressType(osec);
expect(":");
std::string location = getCurrentLocation();
if (consume("AT"))
- cmd->lmaExpr = readParenExpr();
+ osec->lmaExpr = readParenExpr();
if (consume("ALIGN"))
- cmd->alignExpr = checkAlignment(readParenExpr(), location);
+ osec->alignExpr = checkAlignment(readParenExpr(), location);
if (consume("SUBALIGN"))
- cmd->subalignExpr = checkAlignment(readParenExpr(), location);
+ osec->subalignExpr = checkAlignment(readParenExpr(), location);
// Parse constraints.
if (consume("ONLY_IF_RO"))
- cmd->constraint = ConstraintKind::ReadOnly;
+ osec->constraint = ConstraintKind::ReadOnly;
if (consume("ONLY_IF_RW"))
- cmd->constraint = ConstraintKind::ReadWrite;
+ osec->constraint = ConstraintKind::ReadWrite;
expect("{");
while (!errorCount() && !consume("}")) {
@@ -885,9 +931,9 @@ OutputSection *ScriptParser::readOutputSectionDescription(StringRef outSec) {
if (tok == ";") {
// Empty commands are allowed. Do nothing here.
} else if (SymbolAssignment *assign = readAssignment(tok)) {
- cmd->commands.push_back(assign);
+ osec->commands.push_back(assign);
} else if (ByteCommand *data = readByteCommand(tok)) {
- cmd->commands.push_back(data);
+ osec->commands.push_back(data);
} else if (tok == "CONSTRUCTORS") {
// CONSTRUCTORS is a keyword to make the linker recognize C++ ctors/dtors
// by name. This is for very old file formats such as ECOFF/XCOFF.
@@ -898,13 +944,15 @@ OutputSection *ScriptParser::readOutputSectionDescription(StringRef outSec) {
// https://sourceware.org/binutils/docs/ld/Output-Section-Data.html
if (peek() != "(")
setError("( expected, but got " + peek());
- cmd->filler = readFill();
+ osec->filler = readFill();
} else if (tok == "SORT") {
readSort();
} else if (tok == "INCLUDE") {
readInclude();
+ } else if (tok == "(" || tok == ")") {
+ setError("expected filename pattern");
} else if (peek() == "(") {
- cmd->commands.push_back(readInputSectionDescription(tok));
+ osec->commands.push_back(readInputSectionDescription(tok));
} else {
// We have a file name and no input sections description. It is not a
// commonly used syntax, but still acceptable. In that case, all sections
@@ -914,27 +962,27 @@ OutputSection *ScriptParser::readOutputSectionDescription(StringRef outSec) {
// case above.
auto *isd = make<InputSectionDescription>(tok);
isd->sectionPatterns.push_back({{}, StringMatcher("*")});
- cmd->commands.push_back(isd);
+ osec->commands.push_back(isd);
}
}
if (consume(">"))
- cmd->memoryRegionName = std::string(next());
+ osec->memoryRegionName = std::string(next());
if (consume("AT")) {
expect(">");
- cmd->lmaRegionName = std::string(next());
+ osec->lmaRegionName = std::string(next());
}
- if (cmd->lmaExpr && !cmd->lmaRegionName.empty())
+ if (osec->lmaExpr && !osec->lmaRegionName.empty())
error("section can't have both LMA and a load region");
- cmd->phdrs = readOutputSectionPhdrs();
+ osec->phdrs = readOutputSectionPhdrs();
if (peek() == "=" || peek().startswith("=")) {
inExpr = true;
consume("=");
- cmd->filler = readFill();
+ osec->filler = readFill();
inExpr = false;
}
@@ -942,7 +990,7 @@ OutputSection *ScriptParser::readOutputSectionDescription(StringRef outSec) {
consume(",");
if (script->referencedSymbols.size() > symbolsReferenced)
- cmd->expressionsUseSymbols = true;
+ osec->expressionsUseSymbols = true;
return cmd;
}
@@ -969,7 +1017,14 @@ std::array<uint8_t, 4> ScriptParser::readFill() {
SymbolAssignment *ScriptParser::readProvideHidden(bool provide, bool hidden) {
expect("(");
- SymbolAssignment *cmd = readSymbolAssignment(next());
+ StringRef name = next(), eq = peek();
+ if (eq != "=") {
+ setError("= expected, but got " + next());
+ while (!atEOF() && next() != ")")
+ ;
+ return nullptr;
+ }
+ SymbolAssignment *cmd = readSymbolAssignment(name);
cmd->provide = provide;
cmd->hidden = hidden;
expect(")");
@@ -983,14 +1038,24 @@ SymbolAssignment *ScriptParser::readAssignment(StringRef tok) {
size_t oldPos = pos;
SymbolAssignment *cmd = nullptr;
- if (peek() == "=" || peek() == "+=")
+ const StringRef op = peek();
+ if (op.startswith("=")) {
+ // Support = followed by an expression without whitespace.
+ SaveAndRestore<bool> saved(inExpr, true);
+ cmd = readSymbolAssignment(tok);
+ } else if ((op.size() == 2 && op[1] == '=' && strchr("*/+-&|", op[0])) ||
+ op == "<<=" || op == ">>=") {
cmd = readSymbolAssignment(tok);
- else if (tok == "PROVIDE")
+ } else if (tok == "PROVIDE") {
+ SaveAndRestore<bool> saved(inExpr, true);
cmd = readProvideHidden(true, false);
- else if (tok == "HIDDEN")
+ } else if (tok == "HIDDEN") {
+ SaveAndRestore<bool> saved(inExpr, true);
cmd = readProvideHidden(false, true);
- else if (tok == "PROVIDE_HIDDEN")
+ } else if (tok == "PROVIDE_HIDDEN") {
+ SaveAndRestore<bool> saved(inExpr, true);
cmd = readProvideHidden(true, true);
+ }
if (cmd) {
cmd->commandString =
@@ -1004,11 +1069,38 @@ SymbolAssignment *ScriptParser::readAssignment(StringRef tok) {
SymbolAssignment *ScriptParser::readSymbolAssignment(StringRef name) {
name = unquote(name);
StringRef op = next();
- assert(op == "=" || op == "+=");
+ assert(op == "=" || op == "*=" || op == "/=" || op == "+=" || op == "-=" ||
+ op == "&=" || op == "|=" || op == "<<=" || op == ">>=");
+ // Note: GNU ld does not support %= or ^=.
Expr e = readExpr();
- if (op == "+=") {
+ if (op != "=") {
std::string loc = getCurrentLocation();
- e = [=] { return add(script->getSymbolValue(name, loc), e()); };
+ e = [=, c = op[0]]() -> ExprValue {
+ ExprValue lhs = script->getSymbolValue(name, loc);
+ switch (c) {
+ case '*':
+ return lhs.getValue() * e().getValue();
+ case '/':
+ if (uint64_t rv = e().getValue())
+ return lhs.getValue() / rv;
+ error(loc + ": division by zero");
+ return 0;
+ case '+':
+ return add(lhs, e());
+ case '-':
+ return sub(lhs, e());
+ case '<':
+ return lhs.getValue() << e().getValue();
+ case '>':
+ return lhs.getValue() >> e().getValue();
+ case '&':
+ return lhs.getValue() & e().getValue();
+ case '|':
+ return lhs.getValue() | e().getValue();
+ default:
+ llvm_unreachable("");
+ }
+ };
}
return make<SymbolAssignment>(name, e, getCurrentLocation());
}
@@ -1082,11 +1174,11 @@ Expr ScriptParser::combine(StringRef op, Expr l, Expr r) {
Expr ScriptParser::readExpr1(Expr lhs, int minPrec) {
while (!atEOF() && !errorCount()) {
// Read an operator and an expression.
- if (consume("?"))
- return readTernary(lhs);
StringRef op1 = peek();
if (precedence(op1) < minPrec)
break;
+ if (consume("?"))
+ return readTernary(lhs);
skip();
Expr rhs = readPrimary();
@@ -1244,9 +1336,9 @@ StringRef ScriptParser::readParenLiteral() {
return tok;
}
-static void checkIfExists(OutputSection *cmd, StringRef location) {
- if (cmd->location.empty() && script->errorOnMissingSection)
- error(location + ": undefined section " + cmd->name);
+static void checkIfExists(const OutputSection &osec, StringRef location) {
+ if (osec.location.empty() && script->errorOnMissingSection)
+ error(location + ": undefined section " + osec.name);
}
static bool isValidSymbolName(StringRef s) {
@@ -1288,11 +1380,11 @@ Expr ScriptParser::readPrimary() {
}
if (tok == "ADDR") {
StringRef name = readParenLiteral();
- OutputSection *sec = script->getOrCreateOutputSection(name);
- sec->usedInExpression = true;
+ OutputSection *osec = &script->getOrCreateOutputSection(name)->osec;
+ osec->usedInExpression = true;
return [=]() -> ExprValue {
- checkIfExists(sec, location);
- return {sec, false, 0, location};
+ checkIfExists(*osec, location);
+ return {osec, false, 0, location};
};
}
if (tok == "ALIGN") {
@@ -1313,10 +1405,10 @@ Expr ScriptParser::readPrimary() {
}
if (tok == "ALIGNOF") {
StringRef name = readParenLiteral();
- OutputSection *cmd = script->getOrCreateOutputSection(name);
+ OutputSection *osec = &script->getOrCreateOutputSection(name)->osec;
return [=] {
- checkIfExists(cmd, location);
- return cmd->alignment;
+ checkIfExists(*osec, location);
+ return osec->alignment;
};
}
if (tok == "ASSERT")
@@ -1329,6 +1421,7 @@ Expr ScriptParser::readPrimary() {
expect(",");
readExpr();
expect(")");
+ seenDataAlign = true;
return [=] {
return alignTo(script->getDot(), std::max((uint64_t)1, e().getValue()));
};
@@ -1348,6 +1441,7 @@ Expr ScriptParser::readPrimary() {
expect(",");
readExpr();
expect(")");
+ seenRelroEnd = true;
Expr e = getPageSize();
return [=] { return alignTo(script->getDot(), e().getValue()); };
}
@@ -1368,11 +1462,11 @@ Expr ScriptParser::readPrimary() {
}
if (tok == "LOADADDR") {
StringRef name = readParenLiteral();
- OutputSection *cmd = script->getOrCreateOutputSection(name);
- cmd->usedInExpression = true;
+ OutputSection *osec = &script->getOrCreateOutputSection(name)->osec;
+ osec->usedInExpression = true;
return [=] {
- checkIfExists(cmd, location);
- return cmd->getLMA();
+ checkIfExists(*osec, location);
+ return osec->getLMA();
};
}
if (tok == "LOG2CEIL") {
@@ -1412,7 +1506,7 @@ Expr ScriptParser::readPrimary() {
}
if (tok == "SIZEOF") {
StringRef name = readParenLiteral();
- OutputSection *cmd = script->getOrCreateOutputSection(name);
+ OutputSection *cmd = &script->getOrCreateOutputSection(name)->osec;
// Linker script does not create an output section if its content is empty.
// We want to allow SIZEOF(.foo) where .foo is a section which happened to
// be empty.
generated by cgit v1.3 (git 2.53.0) at 2026-03-11 02:11:54 +0000