diff --git a/clang/include/clang/Driver/Options.td b/clang/include/clang/Driver/Options.td --- a/clang/include/clang/Driver/Options.td +++ b/clang/include/clang/Driver/Options.td @@ -2125,6 +2125,10 @@ HelpText<"Enable linker relaxation">; def mno_relax : Flag<["-"], "mno-relax">, Group, HelpText<"Disable linker relaxation">; +def msave_restore : Flag<["-"], "msave-restore">, Group, + HelpText<"Enable using library calls for save and restore">; +def mno_save_restore : Flag<["-"], "mno-save-restore">, Group, + HelpText<"Disable using library calls for save and restore">; def munaligned_access : Flag<["-"], "munaligned-access">, Group, HelpText<"Allow memory accesses to be unaligned (AArch32/AArch64 only)">; diff --git a/clang/lib/Driver/ToolChains/Arch/RISCV.cpp b/clang/lib/Driver/ToolChains/Arch/RISCV.cpp --- a/clang/lib/Driver/ToolChains/Arch/RISCV.cpp +++ b/clang/lib/Driver/ToolChains/Arch/RISCV.cpp @@ -358,6 +358,16 @@ else Features.push_back("-relax"); + // -mno-save-restore is default, unless -msave-restore is specified. + if (Args.hasFlag(options::OPT_msave_restore, options::OPT_mno_save_restore, false)) { + Features.push_back("+save-restore"); + // ... but we don't yet support +save-restore, so issue a warning. + D.Diag(diag::warn_drv_clang_unsupported) + << Args.getLastArg(options::OPT_msave_restore)->getAsString(Args); + } else { + Features.push_back("-save-restore"); + } + // Now add any that the user explicitly requested on the command line, // which may override the defaults. handleTargetFeaturesGroup(Args, Features, options::OPT_m_riscv_Features_Group); diff --git a/clang/test/Driver/riscv-features.c b/clang/test/Driver/riscv-features.c --- a/clang/test/Driver/riscv-features.c +++ b/clang/test/Driver/riscv-features.c @@ -3,11 +3,20 @@ // CHECK: fno-signed-char +// RUN: %clang -target riscv32-unknown-elf -### %s 2>&1 | FileCheck %s -check-prefix=DEFAULT + // RUN: %clang -target riscv32-unknown-elf -### %s -mrelax 2>&1 | FileCheck %s -check-prefix=RELAX // RUN: %clang -target riscv32-unknown-elf -### %s -mno-relax 2>&1 | FileCheck %s -check-prefix=NO-RELAX -// RUN: %clang -target riscv32-unknown-elf -### %s 2>&1 | FileCheck %s -check-prefix=DEFAULT // RELAX: "-target-feature" "+relax" // NO-RELAX: "-target-feature" "-relax" // DEFAULT: "-target-feature" "+relax" // DEFAULT-NOT: "-target-feature" "-relax" + +// RUN: %clang -target riscv32-unknown-elf -### %s -msave-restore 2>&1 | FileCheck %s -check-prefix=SAVE-RESTORE +// RUN: %clang -target riscv32-unknown-elf -### %s -mno-save-restore 2>&1 | FileCheck %s -check-prefix=NO-SAVE-RESTORE + +// SAVE-RESTORE: "-target-feature" "+save-restore" +// NO-SAVE-RESTORE: "-target-feature" "-save-restore" +// DEFAULT: "-target-feature" "-save-restore" +// DEFAULT-NOT: "-target-feature" "+save-restore"