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-rw-r--r--lld/ELF/ICF.cpp54
-rw-r--r--lld/ELF/SymbolTable.cpp6
-rw-r--r--lld/ELF/SymbolTable.h1
-rw-r--r--lld/test/ELF/aarch64-got-merging-icf.s95
-rw-r--r--lld/test/ELF/icf-preemptible.s6
5 files changed, 1 insertions, 161 deletions
diff --git a/lld/ELF/ICF.cpp b/lld/ELF/ICF.cpp
index 1882116..77fe7c5 100644
--- a/lld/ELF/ICF.cpp
+++ b/lld/ELF/ICF.cpp
@@ -80,7 +80,6 @@
#include "SymbolTable.h"
#include "Symbols.h"
#include "SyntheticSections.h"
-#include "llvm/ADT/EquivalenceClasses.h"
#include "llvm/BinaryFormat/ELF.h"
#include "llvm/Object/ELF.h"
#include "llvm/Support/Parallel.h"
@@ -334,28 +333,6 @@ bool ICF<ELFT>::equalsConstant(const InputSection *a, const InputSection *b) {
: constantEq(a, ra.relas, b, rb.relas);
}
-template <class RelTy>
-static SmallVector<Symbol *> getReloc(const InputSection *sec,
- Relocs<RelTy> relocs) {
- SmallVector<Symbol *> syms;
- for (auto ri = relocs.begin(), re = relocs.end(); ri != re; ++ri) {
- Symbol &sym = sec->file->getRelocTargetSym(*ri);
- syms.push_back(&sym);
- }
- return syms;
-}
-
-template <class ELFT>
-static SmallVector<Symbol *> getRelocTargetSyms(const InputSection *sec) {
- const RelsOrRelas<ELFT> rel = sec->template relsOrRelas<ELFT>();
- if (rel.areRelocsCrel())
- return getReloc(sec, rel.crels);
- if (rel.areRelocsRel())
- return getReloc(sec, rel.rels);
-
- return getReloc(sec, rel.relas);
-}
-
// Compare two lists of relocations. Returns true if all pairs of
// relocations point to the same section in terms of ICF.
template <class ELFT>
@@ -560,28 +537,14 @@ template <class ELFT> void ICF<ELFT>::run() {
auto print = [&ctx = ctx]() -> ELFSyncStream {
return {ctx, ctx.arg.printIcfSections ? DiagLevel::Msg : DiagLevel::None};
};
-
- EquivalenceClasses<Symbol *> symbolEquivalence;
// Merge sections by the equivalence class.
- // Merge symbols identified as equivalent during ICF.
forEachClassRange(0, sections.size(), [&](size_t begin, size_t end) {
if (end - begin == 1)
return;
print() << "selected section " << sections[begin];
- SmallVector<Symbol *> syms = getRelocTargetSyms<ELFT>(sections[begin]);
for (size_t i = begin + 1; i < end; ++i) {
print() << " removing identical section " << sections[i];
sections[begin]->replace(sections[i]);
- SmallVector<Symbol *> replacedSyms =
- getRelocTargetSyms<ELFT>(sections[i]);
- assert(syms.size() == replacedSyms.size() &&
- "Should have same number of syms!");
- for (size_t i = 0; i < syms.size(); i++) {
- if (syms[i] == replacedSyms[i] || !syms[i]->isGlobal() ||
- !replacedSyms[i]->isGlobal())
- continue;
- symbolEquivalence.unionSets(syms[i], replacedSyms[i]);
- }
// At this point we know sections merged are fully identical and hence
// we want to remove duplicate implicit dependencies such as link order
@@ -600,26 +563,11 @@ template <class ELFT> void ICF<ELFT>::run() {
d->folded = true;
}
};
- for (Symbol *sym : ctx.symtab->getSymbols()) {
+ for (Symbol *sym : ctx.symtab->getSymbols())
fold(sym);
- auto it = symbolEquivalence.findLeader(sym);
- if (it != symbolEquivalence.member_end() && *it != sym) {
- print() << "redirecting '" << sym->getName() << "' in symtab to '"
- << (*it)->getName() << "'";
- ctx.symtab->redirect(sym, *it);
- }
- }
parallelForEach(ctx.objectFiles, [&](ELFFileBase *file) {
for (Symbol *sym : file->getLocalSymbols())
fold(sym);
- for (Symbol *&sym : file->getMutableGlobalSymbols()) {
- auto it = symbolEquivalence.findLeader(sym);
- if (it != symbolEquivalence.member_end() && *it != sym) {
- print() << "redirecting '" << sym->getName() << "' to '"
- << (*it)->getName() << "'";
- sym = *it;
- }
- }
});
// InputSectionDescription::sections is populated by processSectionCommands().
diff --git a/lld/ELF/SymbolTable.cpp b/lld/ELF/SymbolTable.cpp
index 91e47e1..b8a70d4 100644
--- a/lld/ELF/SymbolTable.cpp
+++ b/lld/ELF/SymbolTable.cpp
@@ -29,12 +29,6 @@ using namespace llvm::ELF;
using namespace lld;
using namespace lld::elf;
-void SymbolTable::redirect(Symbol *from, Symbol *to) {
- int &fromIdx = symMap[CachedHashStringRef(from->getName())];
- const int toIdx = symMap[CachedHashStringRef(to->getName())];
- fromIdx = toIdx;
-}
-
void SymbolTable::wrap(Symbol *sym, Symbol *real, Symbol *wrap) {
// Redirect __real_foo to the original foo and foo to the original __wrap_foo.
int &idx1 = symMap[CachedHashStringRef(sym->getName())];
diff --git a/lld/ELF/SymbolTable.h b/lld/ELF/SymbolTable.h
index e3a39ba..d644374 100644
--- a/lld/ELF/SymbolTable.h
+++ b/lld/ELF/SymbolTable.h
@@ -41,7 +41,6 @@ public:
SymbolTable(Ctx &ctx) : ctx(ctx) {}
ArrayRef<Symbol *> getSymbols() const { return symVector; }
- void redirect(Symbol *from, Symbol *to);
void wrap(Symbol *sym, Symbol *real, Symbol *wrap);
Symbol *insert(StringRef name);
diff --git a/lld/test/ELF/aarch64-got-merging-icf.s b/lld/test/ELF/aarch64-got-merging-icf.s
deleted file mode 100644
index 01d7bdf..0000000
--- a/lld/test/ELF/aarch64-got-merging-icf.s
+++ /dev/null
@@ -1,95 +0,0 @@
-## REQUIRES: aarch64
-## Check that symbols that ICF assumes to be the same get a single GOT entry
-
-# RUN: llvm-mc -filetype=obj -triple=aarch64 %s -o %t
-# RUN: llvm-mc -filetype=obj -crel -triple=aarch64 %s -o %tcrel
-# RUN: ld.lld %t -o %t2 --icf=all
-# RUN: ld.lld %tcrel -o %tcrel2 --icf=all
-
-# RUN: llvm-objdump --section-headers %t2 | FileCheck %s --check-prefix=EXE
-# RUN: llvm-objdump --section-headers %tcrel2 | FileCheck %s --check-prefix=EXE
-
-# RUN: ld.lld -shared %t -o %t3 --icf=all
-# RUN: ld.lld -shared %tcrel -o %tcrel3 --icf=all
-
-# RUN: llvm-objdump --section-headers %t3 | FileCheck %s --check-prefix=DSO
-# RUN: llvm-objdump --section-headers %tcrel3 | FileCheck %s --check-prefix=DSO
-
-## All global g* symbols should merge into a single GOT entry while non-global
-## gets its own GOT entry.
-# EXE: {{.*}}.got 00000010{{.*}}
-
-## When symbols are preemptible in DSO mode, GOT entries wouldn't be merged
-# DSO: {{.*}}.got 00000028{{.*}}
-
-.addrsig
-
-callee:
-ret
-
-.macro f, index, isglobal
-
-# (Kept unique) first instruction of the GOT code sequence
-.section .text.f1_\index,"ax",@progbits
-f1_\index:
-adrp x0, :got:g\index
-mov x1, #\index
-b f2_\index
-
-# Folded, second instruction of the GOT code sequence
-.section .text.f2_\index,"ax",@progbits
-f2_\index:
-ldr x0, [x0, :got_lo12:g\index]
-b callee
-
-# Folded
-.ifnb \isglobal
-.globl g\index
-.endif
-.section .rodata.g\index,"a",@progbits
-g_\index:
-.long 111
-.long 122
-
-g\index:
-.byte 123
-
-.section .text._start,"ax",@progbits
-bl f1_\index
-
-.endm
-
-## Another set of sections merging: g1 <- g2. Linker should be able to
-## resolve both g1 and g2 to g0 based on ICF on previous sections.
-
-.section .text.t1_0,"ax",@progbits
-t1_0:
-adrp x2, :got:g1
-mov x3, #1
-b t2_0
-
-.section .text.t2_0,"ax",@progbits
-t2_0:
-ldr x2, [x2, :got_lo12:g1]
-b callee
-
-.section .text.t1_1,"ax",@progbits
-t1_1:
-adrp x2, :got:g2
-mov x3, #2
-b t2_1
-
-.section .text.t2_1,"ax",@progbits
-t2_1:
-ldr x2, [x2, :got_lo12:g2]
-b callee
-
-.section .text._start,"ax",@progbits
-.globl _start
-_start:
-
-f 0 1
-f 1 1
-f 2 1
-f 3 1
-f 4
diff --git a/lld/test/ELF/icf-preemptible.s b/lld/test/ELF/icf-preemptible.s
index 9352493..4bd1eca 100644
--- a/lld/test/ELF/icf-preemptible.s
+++ b/lld/test/ELF/icf-preemptible.s
@@ -17,12 +17,6 @@
# EXE-NEXT: selected section {{.*}}:(.text.h1)
# EXE-NEXT: removing identical section {{.*}}:(.text.h2)
# EXE-NEXT: removing identical section {{.*}}:(.text.h3)
-# EXE-NEXT: redirecting 'f2' in symtab to 'f1'
-# EXE-NEXT: redirecting 'g2' in symtab to 'g1'
-# EXE-NEXT: redirecting 'g3' in symtab to 'g1'
-# EXE-NEXT: redirecting 'f2' to 'f1'
-# EXE-NEXT: redirecting 'g2' to 'g1'
-# EXE-NEXT: redirecting 'g3' to 'g1'
# EXE-NOT: {{.}}
## Definitions are preemptible in a DSO. Only leaf functions can be folded.
generated by cgit v1.1 at 2025-08-03 07:43:25 +0000