Hi Tanya, On Tue, Nov 3, 2009 at 5:18 PM, Tanya Lattner <[email protected]> wrote: > Author: tbrethou > Date: Tue Nov 3 19:18:09 2009 > New Revision: 85991 > > URL: http://llvm.org/viewvc/llvm-project?rev=85991&view=rev > Log: > Merge constant array and structures. This will create a global variables for > arrays and structs that are constant and their initializer is constant. It is > on by default but can be disable with the flag -fno-merge-all-constants.
Looks good, but it would be good to have a test case that demonstrates the opt and verifies that -fno-merge-all-constants does the right thing. - Daniel > Modified: > cfe/trunk/include/clang/Driver/Options.def > cfe/trunk/include/clang/Frontend/CompileOptions.h > cfe/trunk/lib/CodeGen/CGDecl.cpp > cfe/trunk/lib/Driver/Tools.cpp > cfe/trunk/tools/clang-cc/clang-cc.cpp > > Modified: cfe/trunk/include/clang/Driver/Options.def > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Driver/Options.def?rev=85991&r1=85990&r2=85991&view=diff > > ============================================================================== > --- cfe/trunk/include/clang/Driver/Options.def (original) > +++ cfe/trunk/include/clang/Driver/Options.def Tue Nov 3 19:18:09 2009 > @@ -404,6 +404,7 @@ > OPTION("-flimited-precision=", flimited_precision_EQ, Joined, f_Group, > INVALID, "", 0, 0, 0) > OPTION("-flto", flto, Flag, f_Group, INVALID, "", 0, 0, 0) > OPTION("-fmath-errno", fmath_errno, Flag, f_Group, INVALID, "", 0, 0, 0) > +OPTION("-fmerge-all-constants", fmerge_all_constants, Flag, f_Group, > INVALID, "", 0, 0, 0) > OPTION("-fmessage-length=", fmessage_length_EQ, Joined, f_Group, INVALID, > "", 0, 0, 0) > OPTION("-fms-extensions", fms_extensions, Flag, f_Group, INVALID, "", 0, 0, > 0) > OPTION("-fmudflapth", fmudflapth, Flag, f_Group, INVALID, "", 0, 0, 0) > @@ -428,6 +429,7 @@ > OPTION("-fno-inline", fno_inline, Flag, clang_ignored_f_Group, INVALID, "", > 0, 0, 0) > OPTION("-fno-keep-inline-functions", fno_keep_inline_functions, Flag, > clang_ignored_f_Group, INVALID, "", 0, 0, 0) > OPTION("-fno-math-errno", fno_math_errno, Flag, f_Group, INVALID, "", 0, 0, > 0) > +OPTION("-fno-merge-all-constants", fno_merge_all_constants, Flag, f_Group, > INVALID, "", 0, 0, 0) > OPTION("-fno-omit-frame-pointer", fno_omit_frame_pointer, Flag, f_Group, > INVALID, "", 0, 0, 0) > OPTION("-fno-pascal-strings", fno_pascal_strings, Flag, f_Group, INVALID, > "", 0, 0, 0) > OPTION("-fno-rtti", fno_rtti, Flag, f_Group, INVALID, "", 0, 0, 0) > > Modified: cfe/trunk/include/clang/Frontend/CompileOptions.h > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Frontend/CompileOptions.h?rev=85991&r1=85990&r2=85991&view=diff > > ============================================================================== > --- cfe/trunk/include/clang/Frontend/CompileOptions.h (original) > +++ cfe/trunk/include/clang/Frontend/CompileOptions.h Tue Nov 3 19:18:09 2009 > @@ -43,7 +43,8 @@ > unsigned NoCommon : 1; /// Set when -fno-common or C++ is enabled. > unsigned DisableRedZone : 1; /// Set when -mno-red-zone is enabled. > unsigned NoImplicitFloat : 1; /// Set when -mno-implicit-float is enabled. > - > + unsigned MergeAllConstants : 1; // Merge identical constants. > + > /// Inlining - The kind of inlining to perform. > InliningMethod Inlining; > > @@ -67,6 +68,7 @@ > Inlining = NoInlining; > DisableRedZone = 0; > NoImplicitFloat = 0; > + MergeAllConstants = 1; > } > }; > > > Modified: cfe/trunk/lib/CodeGen/CGDecl.cpp > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CGDecl.cpp?rev=85991&r1=85990&r2=85991&view=diff > > ============================================================================== > --- cfe/trunk/lib/CodeGen/CGDecl.cpp (original) > +++ cfe/trunk/lib/CodeGen/CGDecl.cpp Tue Nov 3 19:18:09 2009 > @@ -19,6 +19,7 @@ > #include "clang/AST/DeclObjC.h" > #include "clang/Basic/SourceManager.h" > #include "clang/Basic/TargetInfo.h" > +#include "clang/Frontend/CompileOptions.h" > #include "llvm/GlobalVariable.h" > #include "llvm/Intrinsics.h" > #include "llvm/Target/TargetData.h" > @@ -316,6 +317,20 @@ > llvm::Value *DeclPtr; > if (Ty->isConstantSizeType()) { > if (!Target.useGlobalsForAutomaticVariables()) { > + > + // All constant structs and arrays should be global if > + // their initializer is constant and if the element type is POD. > + if (CGM.getCompileOpts().MergeAllConstants) { > + if (Ty.isConstant(getContext()) > + && (Ty->isArrayType() || Ty->isRecordType()) > + && (D.getInit() > + && D.getInit()->isConstantInitializer(getContext())) > + && Ty->isPODType()) { > + EmitStaticBlockVarDecl(D); > + return; > + } > + } > + > // A normal fixed sized variable becomes an alloca in the entry block. > const llvm::Type *LTy = ConvertTypeForMem(Ty); > Align = getContext().getDeclAlignInBytes(&D); > > Modified: cfe/trunk/lib/Driver/Tools.cpp > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Driver/Tools.cpp?rev=85991&r1=85990&r2=85991&view=diff > > ============================================================================== > --- cfe/trunk/lib/Driver/Tools.cpp (original) > +++ cfe/trunk/lib/Driver/Tools.cpp Tue Nov 3 19:18:09 2009 > @@ -703,6 +703,9 @@ > CmdArgs.push_back("--debug-pass=Structure"); > if (Args.hasArg(options::OPT_fdebug_pass_arguments)) > CmdArgs.push_back("--debug-pass=Arguments"); > + if (!Args.hasFlag(options::OPT_fmerge_all_constants, > + options::OPT_fno_merge_all_constants)) > + CmdArgs.push_back("--no-merge-all-constants"); > > // This is a coarse approximation of what llvm-gcc actually does, both > // -fasynchronous-unwind-tables and -fnon-call-exceptions interact in more > > Modified: cfe/trunk/tools/clang-cc/clang-cc.cpp > URL: > http://llvm.org/viewvc/llvm-project/cfe/trunk/tools/clang-cc/clang-cc.cpp?rev=85991&r1=85990&r2=85991&view=diff > > ============================================================================== > --- cfe/trunk/tools/clang-cc/clang-cc.cpp (original) > +++ cfe/trunk/tools/clang-cc/clang-cc.cpp Tue Nov 3 19:18:09 2009 > @@ -653,6 +653,10 @@ > NoElideConstructors("fno-elide-constructors", > llvm::cl::desc("Disable C++ copy constructor elision")); > > +static llvm::cl::opt<bool> > +NoMergeConstants("fno-merge-all-constants", > + llvm::cl::desc("Disallow merging of constants.")); > + > static llvm::cl::opt<std::string> > TargetABI("target-abi", > llvm::cl::desc("Target a particular ABI type")); > @@ -1372,6 +1376,8 @@ > > Opts.DisableRedZone = DisableRedZone; > Opts.NoImplicitFloat = NoImplicitFloat; > + > + Opts.MergeAllConstants = !NoMergeConstants; > } > > //===----------------------------------------------------------------------===// > > > _______________________________________________ > cfe-commits mailing list > [email protected] > http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits > _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
