[RISCV] Allow -mcmodel= to accept large for RV64

Author: tclin914

clang/lib/Driver/ToolChains/CommonArgs.cpp

@@ -2906,7 +2906,8 @@ void tools::addMCModel(const Driver &D, const llvm::opt::ArgList &Args,
         CM = "small";
       else if (CM == "medany")
         CM = "medium";
-      Ok = CM == "small" || CM == "medium";
+      Ok = CM == "small" || CM == "medium" ||
+           (CM == "large" && Triple.isRISCV64());
     } else if (Triple.getArch() == llvm::Triple::x86_64) {
       Ok = llvm::is_contained({"small", "kernel", "medium", "large", "tiny"},
                               CM);

clang/test/Driver/riscv-mcmodel.c

@@ -10,5 +10,11 @@
 // RUN: %clang --target=riscv32 -### -c -mcmodel=medany %s 2>&1 | FileCheck --check-prefix=MEDIUM %s
 // RUN: %clang --target=riscv64 -### -c -mcmodel=medany %s 2>&1 | FileCheck --check-prefix=MEDIUM %s
 
+// RUN: not %clang --target=riscv32 -### -c -mcmodel=large %s 2>&1 | FileCheck --check-prefix=ERR-LARGE %s
+// RUN: %clang --target=riscv64 -### -c -mcmodel=large %s 2>&1 | FileCheck --check-prefix=LARGE %s
+
 // SMALL: "-mcmodel=small"
 // MEDIUM: "-mcmodel=medium"
+// LARGE: "-mcmodel=large"
+
+// ERR-LARGE:  error: unsupported argument 'large' to option '-mcmodel=' for target 'riscv32'