r324438 - Support `#pragma comment(lib, "name")` in the frontend for ELF
Saleem Abdulrasool via cfe-commits
cfe-commits at lists.llvm.org
Tue Feb 6 17:46:46 PST 2018
Author: compnerd
Date: Tue Feb 6 17:46:46 2018
New Revision: 324438
URL: http://llvm.org/viewvc/llvm-project?rev=324438&view=rev
Log:
Support `#pragma comment(lib, "name")` in the frontend for ELF
This adds the frontend support required to support the use of the
comment pragma to enable auto linking on ELFish targets. This is a
generic ELF extension supported by LLVM. We need to change the handling
for the "dependentlib" in order to accommodate the previously discussed
encoding for the dependent library descriptor. Without the custom
handling of the PCK_Lib directive, the -l prefixed option would be
encoded into the resulting object (which is treated as a frontend
error).
Added:
cfe/trunk/test/CodeGen/elf-linker-options.c
cfe/trunk/test/Preprocessor/pragma-comment-linux.c
Modified:
cfe/trunk/docs/LanguageExtensions.rst
cfe/trunk/lib/CodeGen/CodeGenModule.cpp
cfe/trunk/lib/CodeGen/CodeGenModule.h
cfe/trunk/lib/Parse/ParsePragma.cpp
cfe/trunk/test/CodeGen/pragma-comment.c
cfe/trunk/test/Preprocessor/pragma_microsoft.c
Modified: cfe/trunk/docs/LanguageExtensions.rst
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/docs/LanguageExtensions.rst?rev=324438&r1=324437&r2=324438&view=diff
==============================================================================
--- cfe/trunk/docs/LanguageExtensions.rst (original)
+++ cfe/trunk/docs/LanguageExtensions.rst Tue Feb 6 17:46:46 2018
@@ -2725,3 +2725,11 @@ The ``#pragma clang section`` directive
* The decision about which section-kind applies to each global is taken in the back-end.
Once the section-kind is known, appropriate section name, as specified by the user using
``#pragma clang section`` directive, is applied to that global.
+
+Specifying Linker Options on ELF Targets
+========================================
+
+The ``#pragma comment(lib, ...)`` directive is supported on all ELF targets.
+The second parameter is the library name (without the traditional Unix prefix of
+``lib``). This allows you to provide an implicit link of dependent libraries.
+
Modified: cfe/trunk/lib/CodeGen/CodeGenModule.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.cpp?rev=324438&r1=324437&r2=324438&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.cpp Tue Feb 6 17:46:46 2018
@@ -1411,6 +1411,12 @@ void CodeGenModule::AddDetectMismatch(St
LinkerOptionsMetadata.push_back(llvm::MDNode::get(getLLVMContext(), MDOpts));
}
+void CodeGenModule::AddELFLibDirective(StringRef Lib) {
+ auto &C = getLLVMContext();
+ LinkerOptionsMetadata.push_back(llvm::MDNode::get(
+ C, {llvm::MDString::get(C, "lib"), llvm::MDString::get(C, Lib)}));
+}
+
void CodeGenModule::AddDependentLib(StringRef Lib) {
llvm::SmallString<24> Opt;
getTargetCodeGenInfo().getDependentLibraryOption(Lib, Opt);
@@ -4329,7 +4335,11 @@ void CodeGenModule::EmitTopLevelDecl(Dec
AppendLinkerOptions(PCD->getArg());
break;
case PCK_Lib:
- AddDependentLib(PCD->getArg());
+ if (getTarget().getTriple().isOSBinFormatELF() &&
+ !getTarget().getTriple().isPS4())
+ AddELFLibDirective(PCD->getArg());
+ else
+ AddDependentLib(PCD->getArg());
break;
case PCK_Compiler:
case PCK_ExeStr:
Modified: cfe/trunk/lib/CodeGen/CodeGenModule.h
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenModule.h?rev=324438&r1=324437&r2=324438&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenModule.h (original)
+++ cfe/trunk/lib/CodeGen/CodeGenModule.h Tue Feb 6 17:46:46 2018
@@ -1094,6 +1094,8 @@ public:
/// value.
void AddDependentLib(StringRef Lib);
+ void AddELFLibDirective(StringRef Lib);
+
llvm::GlobalVariable::LinkageTypes getFunctionLinkage(GlobalDecl GD);
void setFunctionLinkage(GlobalDecl GD, llvm::Function *F) {
Modified: cfe/trunk/lib/Parse/ParsePragma.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Parse/ParsePragma.cpp?rev=324438&r1=324437&r2=324438&view=diff
==============================================================================
--- cfe/trunk/lib/Parse/ParsePragma.cpp (original)
+++ cfe/trunk/lib/Parse/ParsePragma.cpp Tue Feb 6 17:46:46 2018
@@ -295,7 +295,8 @@ void Parser::initializePragmaHandlers()
OpenMPHandler.reset(new PragmaNoOpenMPHandler());
PP.AddPragmaHandler(OpenMPHandler.get());
- if (getLangOpts().MicrosoftExt || getTargetInfo().getTriple().isPS4()) {
+ if (getLangOpts().MicrosoftExt ||
+ getTargetInfo().getTriple().isOSBinFormatELF()) {
MSCommentHandler.reset(new PragmaCommentHandler(Actions));
PP.AddPragmaHandler(MSCommentHandler.get());
}
@@ -377,7 +378,8 @@ void Parser::resetPragmaHandlers() {
PP.RemovePragmaHandler(OpenMPHandler.get());
OpenMPHandler.reset();
- if (getLangOpts().MicrosoftExt || getTargetInfo().getTriple().isPS4()) {
+ if (getLangOpts().MicrosoftExt ||
+ getTargetInfo().getTriple().isOSBinFormatELF()) {
PP.RemovePragmaHandler(MSCommentHandler.get());
MSCommentHandler.reset();
}
@@ -2449,6 +2451,12 @@ void PragmaCommentHandler::HandlePragma(
return;
}
+ if (PP.getTargetInfo().getTriple().isOSBinFormatELF() && Kind != PCK_Lib) {
+ PP.Diag(Tok.getLocation(), diag::warn_pragma_comment_ignored)
+ << II->getName();
+ return;
+ }
+
// On PS4, issue a warning about any pragma comments other than
// #pragma comment lib.
if (PP.getTargetInfo().getTriple().isPS4() && Kind != PCK_Lib) {
Added: cfe/trunk/test/CodeGen/elf-linker-options.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/elf-linker-options.c?rev=324438&view=auto
==============================================================================
--- cfe/trunk/test/CodeGen/elf-linker-options.c (added)
+++ cfe/trunk/test/CodeGen/elf-linker-options.c Tue Feb 6 17:46:46 2018
@@ -0,0 +1,7 @@
+// RUN: %clang_cc1 -triple i686---elf -emit-llvm %s -o - | FileCheck %s
+
+#pragma comment(lib, "alpha")
+
+// CHECK: !llvm.linker.options = !{[[NODE:![0-9]+]]}
+// CHECK: [[NODE]] = !{!"lib", !"alpha"}
+
Modified: cfe/trunk/test/CodeGen/pragma-comment.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/pragma-comment.c?rev=324438&r1=324437&r2=324438&view=diff
==============================================================================
--- cfe/trunk/test/CodeGen/pragma-comment.c (original)
+++ cfe/trunk/test/CodeGen/pragma-comment.c Tue Feb 6 17:46:46 2018
@@ -23,10 +23,9 @@
// CHECK: ![[bar]] = !{!" /bar=2"}
// CHECK: ![[foo]] = !{!" /foo=\22foo bar\22"}
-// LINUX: !{!"-lmsvcrt.lib"}
-// LINUX: !{!"-lkernel32"}
-// LINUX: !{!"-lUSER32.LIB"}
-// LINUX: !{!" /bar=2"}
+// LINUX: !{!"lib", !"msvcrt.lib"}
+// LINUX: !{!"lib", !"kernel32"}
+// LINUX: !{!"lib", !"USER32.LIB"}
// PS4: !{!"\01msvcrt.lib"}
// PS4: !{!"\01kernel32"}
Added: cfe/trunk/test/Preprocessor/pragma-comment-linux.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Preprocessor/pragma-comment-linux.c?rev=324438&view=auto
==============================================================================
--- cfe/trunk/test/Preprocessor/pragma-comment-linux.c (added)
+++ cfe/trunk/test/Preprocessor/pragma-comment-linux.c Tue Feb 6 17:46:46 2018
@@ -0,0 +1,5 @@
+// RUN: %clang_cc1 -triple i686-unknown-linux-gnu -fsyntax-only -verify %s -Wunknown-pragmas
+
+#pragma comment(linker, "")
+// expected-warning at -1 {{'#pragma comment linker' ignored}}
+
Modified: cfe/trunk/test/Preprocessor/pragma_microsoft.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Preprocessor/pragma_microsoft.c?rev=324438&r1=324437&r2=324438&view=diff
==============================================================================
--- cfe/trunk/test/Preprocessor/pragma_microsoft.c (original)
+++ cfe/trunk/test/Preprocessor/pragma_microsoft.c Tue Feb 6 17:46:46 2018
@@ -1,5 +1,5 @@
-// RUN: %clang_cc1 %s -fsyntax-only -verify -fms-extensions -Wunknown-pragmas
-// RUN: not %clang_cc1 %s -fms-extensions -E | FileCheck %s
+// RUN: %clang_cc1 -triple i686-unknown-windows-msvc %s -fsyntax-only -verify -fms-extensions -Wunknown-pragmas
+// RUN: not %clang_cc1 -triple i686-unknown-windows-msvc %s -fms-extensions -E | FileCheck %s
// REQUIRES: non-ps4-sdk
// rdar://6495941
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