Index: cfe/trunk/include/clang/Driver/Options.td =================================================================== --- cfe/trunk/include/clang/Driver/Options.td +++ cfe/trunk/include/clang/Driver/Options.td @@ -586,6 +586,9 @@ def fbracket_depth_EQ : Joined<["-"], "fbracket-depth=">, Group; def fsignaling_math : Flag<["-"], "fsignaling-math">, Group; def fno_signaling_math : Flag<["-"], "fno-signaling-math">, Group; +def fjump_tables : Flag<["-"], "fjump-tables">, Group; +def fno_jump_tables : Flag<["-"], "fno-jump-tables">, Group, Flags<[CC1Option]>, + HelpText<"Do not use jump tables for lowering switches">; def fsanitize_EQ : CommaJoined<["-"], "fsanitize=">, Group, Flags<[CC1Option, CoreOption]>, MetaVarName<"">, HelpText<"Turn on runtime checks for various forms of undefined " Index: cfe/trunk/include/clang/Frontend/CodeGenOptions.def =================================================================== --- cfe/trunk/include/clang/Frontend/CodeGenOptions.def +++ cfe/trunk/include/clang/Frontend/CodeGenOptions.def @@ -149,6 +149,7 @@ ///< selection. CODEGENOPT(UnrollLoops , 1, 0) ///< Control whether loops are unrolled. CODEGENOPT(RerollLoops , 1, 0) ///< Control whether loops are rerolled. +CODEGENOPT(NoUseJumpTables , 1, 0) ///< Set when -fno-jump-tables is enabled CODEGENOPT(UnsafeFPMath , 1, 0) ///< Allow unsafe floating point optzns. CODEGENOPT(UnwindTables , 1, 0) ///< Emit unwind tables. CODEGENOPT(VectorizeBB , 1, 0) ///< Run basic block vectorizer. Index: cfe/trunk/lib/CodeGen/CodeGenFunction.cpp =================================================================== --- cfe/trunk/lib/CodeGen/CodeGenFunction.cpp +++ cfe/trunk/lib/CodeGen/CodeGenFunction.cpp @@ -711,6 +711,10 @@ Fn->addFnAttr(llvm::Attribute::NoInline); } + // Add no-jump-tables value. + Fn->addFnAttr("no-jump-tables", + llvm::toStringRef(CGM.getCodeGenOpts().NoUseJumpTables)); + if (getLangOpts().OpenCL) { // Add metadata for a kernel function. if (const FunctionDecl *FD = dyn_cast_or_null(D)) Index: cfe/trunk/lib/Driver/Tools.cpp =================================================================== --- cfe/trunk/lib/Driver/Tools.cpp +++ cfe/trunk/lib/Driver/Tools.cpp @@ -3891,6 +3891,10 @@ A->claim(); } + if (!Args.hasFlag(options::OPT_fjump_tables, options::OPT_fno_jump_tables, + true)) + CmdArgs.push_back("-fno-jump-tables"); + if (Arg *A = Args.getLastArg(options::OPT_mregparm_EQ)) { CmdArgs.push_back("-mregparm"); CmdArgs.push_back(A->getValue()); Index: cfe/trunk/lib/Frontend/CompilerInvocation.cpp =================================================================== --- cfe/trunk/lib/Frontend/CompilerInvocation.cpp +++ cfe/trunk/lib/Frontend/CompilerInvocation.cpp @@ -606,6 +606,8 @@ Opts.MergeFunctions = Args.hasArg(OPT_fmerge_functions); + Opts.NoUseJumpTables = Args.hasArg(OPT_fno_jump_tables); + Opts.PrepareForLTO = Args.hasArg(OPT_flto, OPT_flto_EQ); const Arg *A = Args.getLastArg(OPT_flto, OPT_flto_EQ); Opts.EmitSummaryIndex = A && A->containsValue("thin"); Index: cfe/trunk/test/CodeGen/nousejumptable.c =================================================================== --- cfe/trunk/test/CodeGen/nousejumptable.c +++ cfe/trunk/test/CodeGen/nousejumptable.c @@ -0,0 +1,8 @@ +// RUN: %clang_cc1 -S -fno-jump-tables %s -emit-llvm -o - | FileCheck %s + +// CHECK-LABEL: main +// CHECK: attributes #0 = {{.*}}"no-jump-tables"="true"{{.*}} + +int main() { + return 0; +}