[llvm] r297649 - [Linker] Provide callback for internalization
Jonas Devlieghere via llvm-commits
llvm-commits at lists.llvm.org
Mon Mar 13 11:08:12 PDT 2017
Author: jdevlieghere
Date: Mon Mar 13 13:08:11 2017
New Revision: 297649
URL: http://llvm.org/viewvc/llvm-project?rev=297649&view=rev
Log:
[Linker] Provide callback for internalization
Differential Revision: https://reviews.llvm.org/D30738
Added:
llvm/trunk/test/Linker/Inputs/linkage.d.ll
Modified:
llvm/trunk/include/llvm/Linker/Linker.h
llvm/trunk/lib/Linker/LinkModules.cpp
llvm/trunk/test/Linker/link-flags.ll
llvm/trunk/tools/llvm-link/llvm-link.cpp
Modified: llvm/trunk/include/llvm/Linker/Linker.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Linker/Linker.h?rev=297649&r1=297648&r2=297649&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Linker/Linker.h (original)
+++ llvm/trunk/include/llvm/Linker/Linker.h Mon Mar 13 13:08:11 2017
@@ -10,6 +10,7 @@
#ifndef LLVM_LINKER_LINKER_H
#define LLVM_LINKER_LINKER_H
+#include "llvm/ADT/StringSet.h"
#include "llvm/Linker/IRMover.h"
namespace llvm {
@@ -29,7 +30,6 @@ public:
None = 0,
OverrideFromSrc = (1 << 0),
LinkOnlyNeeded = (1 << 1),
- InternalizeLinkedSymbols = (1 << 2),
};
Linker(Module &M);
@@ -39,11 +39,19 @@ public:
/// Passing OverrideSymbols as true will have symbols from Src
/// shadow those in the Dest.
///
+ /// Passing InternalizeCallback will have the linker call the function with
+ /// the new module and a list of global value names to be internalized by the
+ /// callback.
+ ///
/// Returns true on error.
- bool linkInModule(std::unique_ptr<Module> Src, unsigned Flags = Flags::None);
+ bool linkInModule(std::unique_ptr<Module> Src, unsigned Flags = Flags::None,
+ std::function<void(Module &, const StringSet<> &)>
+ InternalizeCallback = {});
static bool linkModules(Module &Dest, std::unique_ptr<Module> Src,
- unsigned Flags = Flags::None);
+ unsigned Flags = Flags::None,
+ std::function<void(Module &, const StringSet<> &)>
+ InternalizeCallback = {});
};
} // End llvm namespace
Modified: llvm/trunk/lib/Linker/LinkModules.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Linker/LinkModules.cpp?rev=297649&r1=297648&r2=297649&view=diff
==============================================================================
--- llvm/trunk/lib/Linker/LinkModules.cpp (original)
+++ llvm/trunk/lib/Linker/LinkModules.cpp Mon Mar 13 13:08:11 2017
@@ -14,7 +14,6 @@
#include "LinkDiagnosticInfo.h"
#include "llvm-c/Linker.h"
#include "llvm/ADT/SetVector.h"
-#include "llvm/ADT/StringSet.h"
#include "llvm/IR/Comdat.h"
#include "llvm/IR/DiagnosticPrinter.h"
#include "llvm/IR/GlobalValue.h"
@@ -33,11 +32,18 @@ class ModuleLinker {
std::unique_ptr<Module> SrcM;
SetVector<GlobalValue *> ValuesToLink;
- StringSet<> Internalize;
/// For symbol clashes, prefer those from Src.
unsigned Flags;
+ /// List of global value names that should be internalized.
+ StringSet<> Internalize;
+
+ /// Function that will perform the actual internalization. The reason for a
+ /// callback is that the linker cannot call internalizeModule without
+ /// creating a circular dependency between IPO and the linker.
+ std::function<void(Module &, const StringSet<> &)> InternalizeCallback;
+
/// Used as the callback for lazy linking.
/// The mover has just hit GV and we have to decide if it, and other members
/// of the same comdat, should be linked. Every member to be linked is passed
@@ -46,9 +52,6 @@ class ModuleLinker {
bool shouldOverrideFromSrc() { return Flags & Linker::OverrideFromSrc; }
bool shouldLinkOnlyNeeded() { return Flags & Linker::LinkOnlyNeeded; }
- bool shouldInternalizeLinkedSymbols() {
- return Flags & Linker::InternalizeLinkedSymbols;
- }
bool shouldLinkFromSource(bool &LinkFromSrc, const GlobalValue &Dest,
const GlobalValue &Src);
@@ -104,8 +107,11 @@ class ModuleLinker {
bool linkIfNeeded(GlobalValue &GV);
public:
- ModuleLinker(IRMover &Mover, std::unique_ptr<Module> SrcM, unsigned Flags)
- : Mover(Mover), SrcM(std::move(SrcM)), Flags(Flags) {}
+ ModuleLinker(IRMover &Mover, std::unique_ptr<Module> SrcM, unsigned Flags,
+ std::function<void(Module &, const StringSet<> &)>
+ InternalizeCallback = {})
+ : Mover(Mover), SrcM(std::move(SrcM)), Flags(Flags),
+ InternalizeCallback(std::move(InternalizeCallback)) {}
bool run();
};
@@ -383,7 +389,7 @@ void ModuleLinker::addLazyFor(GlobalValu
!shouldLinkOnlyNeeded())
return;
- if (shouldInternalizeLinkedSymbols())
+ if (InternalizeCallback)
Internalize.insert(GV.getName());
Add(GV);
@@ -397,7 +403,7 @@ void ModuleLinker::addLazyFor(GlobalValu
return;
if (!LinkFromSrc)
continue;
- if (shouldInternalizeLinkedSymbols())
+ if (InternalizeCallback)
Internalize.insert(GV2->getName());
Add(*GV2);
}
@@ -526,7 +532,7 @@ bool ModuleLinker::run() {
}
}
- if (shouldInternalizeLinkedSymbols()) {
+ if (InternalizeCallback) {
for (GlobalValue *GV : ValuesToLink)
Internalize.insert(GV->getName());
}
@@ -547,18 +553,19 @@ bool ModuleLinker::run() {
if (HasErrors)
return true;
- for (auto &P : Internalize) {
- GlobalValue *GV = DstM.getNamedValue(P.first());
- GV->setLinkage(GlobalValue::InternalLinkage);
- }
+ if (InternalizeCallback)
+ InternalizeCallback(DstM, Internalize);
return false;
}
Linker::Linker(Module &M) : Mover(M) {}
-bool Linker::linkInModule(std::unique_ptr<Module> Src, unsigned Flags) {
- ModuleLinker ModLinker(Mover, std::move(Src), Flags);
+bool Linker::linkInModule(
+ std::unique_ptr<Module> Src, unsigned Flags,
+ std::function<void(Module &, const StringSet<> &)> InternalizeCallback) {
+ ModuleLinker ModLinker(Mover, std::move(Src), Flags,
+ std::move(InternalizeCallback));
return ModLinker.run();
}
@@ -571,10 +578,11 @@ bool Linker::linkInModule(std::unique_pt
/// true is returned and ErrorMsg (if not null) is set to indicate the problem.
/// Upon failure, the Dest module could be in a modified state, and shouldn't be
/// relied on to be consistent.
-bool Linker::linkModules(Module &Dest, std::unique_ptr<Module> Src,
- unsigned Flags) {
+bool Linker::linkModules(
+ Module &Dest, std::unique_ptr<Module> Src, unsigned Flags,
+ std::function<void(Module &, const StringSet<> &)> InternalizeCallback) {
Linker L(Dest);
- return L.linkInModule(std::move(Src), Flags);
+ return L.linkInModule(std::move(Src), Flags, std::move(InternalizeCallback));
}
//===----------------------------------------------------------------------===//
Added: llvm/trunk/test/Linker/Inputs/linkage.d.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Linker/Inputs/linkage.d.ll?rev=297649&view=auto
==============================================================================
--- llvm/trunk/test/Linker/Inputs/linkage.d.ll (added)
+++ llvm/trunk/test/Linker/Inputs/linkage.d.ll Mon Mar 13 13:08:11 2017
@@ -0,0 +1,5 @@
+ at Y = global i8 42
+
+define i64 @foo() { ret i64 7 }
+
+ at llvm.used = appending global [2 x i8*] [i8* @Y, i8* bitcast (i64 ()* @foo to i8*)], section "llvm.metadata"
Modified: llvm/trunk/test/Linker/link-flags.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Linker/link-flags.ll?rev=297649&r1=297648&r2=297649&view=diff
==============================================================================
--- llvm/trunk/test/Linker/link-flags.ll (original)
+++ llvm/trunk/test/Linker/link-flags.ll Mon Mar 13 13:08:11 2017
@@ -2,12 +2,15 @@
; RUN: llvm-link -S -only-needed %S/Inputs/linkage.b.ll %S/Inputs/linkage.c.ll | FileCheck %s -check-prefix=B -check-prefix=C -check-prefix=CN
; RUN: llvm-link -S -internalize %S/Inputs/linkage.b.ll %S/Inputs/linkage.c.ll | FileCheck %s -check-prefix=B -check-prefix=CI
; RUN: llvm-link -S -internalize -only-needed %S/Inputs/linkage.b.ll %S/Inputs/linkage.c.ll | FileCheck %s -check-prefix=B -check-prefix=CN
+; RUN: llvm-link -S -internalize %S/Inputs/linkage.b.ll %S/Inputs/linkage.c.ll %S/Inputs/linkage.d.ll | FileCheck %s -check-prefix=B -check-prefix=DI
C-LABEL: @X = global i32 5
CI-LABEL: @X = internal global i32 5
CU-LABEL:@U = global i32 6
CI-LABEL:@U = internal global i32 6
CN-NOT:@U
+DI-LABEL: @Y = global i8 42
+DI-LABEL: @llvm.used = appending global [2 x i8*] [i8* @Y, i8* bitcast (i64 ()* @foo to i8*)], section "llvm.metadata"
B-LABEL: define void @bar() {
@@ -17,3 +20,6 @@ CI-LABEL: define internal i32 @foo()
CU-LABEL:define i32 @unused() {
CI-LABEL:define internal i32 @unused() {
CN-NOT:@unused()
+
+DI-LABEL: define internal i32 @foo.6()
+DI-LABEL: define i64 @foo()
Modified: llvm/trunk/tools/llvm-link/llvm-link.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-link/llvm-link.cpp?rev=297649&r1=297648&r2=297649&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-link/llvm-link.cpp (original)
+++ llvm/trunk/tools/llvm-link/llvm-link.cpp Mon Mar 13 13:08:11 2017
@@ -34,6 +34,7 @@
#include "llvm/Support/SystemUtils.h"
#include "llvm/Support/ToolOutputFile.h"
#include "llvm/Transforms/IPO/FunctionImport.h"
+#include "llvm/Transforms/IPO/Internalize.h"
#include "llvm/Transforms/Utils/FunctionImportUtils.h"
#include <memory>
@@ -272,6 +273,8 @@ static bool linkFiles(const char *argv0,
unsigned Flags) {
// Filter out flags that don't apply to the first file we load.
unsigned ApplicableFlags = Flags & Linker::Flags::OverrideFromSrc;
+ // Similar to some flags, internalization doesn't apply to the first file.
+ bool InternalizeLinkedSymbols = false;
for (const auto &File : Files) {
std::unique_ptr<Module> M = loadFile(argv0, File, Context);
if (!M.get()) {
@@ -311,8 +314,24 @@ static bool linkFiles(const char *argv0,
if (Verbose)
errs() << "Linking in '" << File << "'\n";
- if (L.linkInModule(std::move(M), ApplicableFlags))
+ bool Err = false;
+ if (InternalizeLinkedSymbols) {
+ Err = L.linkInModule(
+ std::move(M), ApplicableFlags, [](Module &M, const StringSet<> &GVS) {
+ internalizeModule(M, [&M, &GVS](const GlobalValue &GV) {
+ return !GV.hasName() || (GVS.count(GV.getName()) == 0);
+ });
+ });
+ } else {
+ Err = L.linkInModule(std::move(M), ApplicableFlags);
+ }
+
+ if (Err)
return false;
+
+ // Internalization applies to linking of subsequent files.
+ InternalizeLinkedSymbols = Internalize;
+
// All linker flags apply to linking of subsequent files.
ApplicableFlags = Flags;
}
@@ -340,8 +359,6 @@ int main(int argc, char **argv) {
Linker L(*Composite);
unsigned Flags = Linker::Flags::None;
- if (Internalize)
- Flags |= Linker::Flags::InternalizeLinkedSymbols;
if (OnlyNeeded)
Flags |= Linker::Flags::LinkOnlyNeeded;
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