Add checking that large code model is disallowed to be used with PIC code model.

Author: tclin914

clang/lib/Driver/ToolChains/CommonArgs.cpp

@@ -2902,6 +2902,10 @@ void tools::addMCModel(const Driver &D, const llvm::opt::ArgList &Args,
     } else if (Triple.isPPC64() || Triple.isOSAIX()) {
       Ok = CM == "small" || CM == "medium" || CM == "large";
     } else if (Triple.isRISCV()) {
+      // Large code model is disallowed to be used with PIC code model.
+      if (CM == "large" && RelocationModel != llvm::Reloc::Static)
+        D.Diag(diag::err_drv_argument_not_allowed_with)
+            << A->getAsString(Args) << "-fpic";
       if (CM == "medlow")
         CM = "small";
       else if (CM == "medany")

clang/test/Driver/riscv-mcmodel.c

@@ -13,8 +13,11 @@
 // 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
 
+// RUN: not %clang --target=riscv64 -### -c -mcmodel=large -fpic %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'
+// ERR-PIC-LARGE:  error: invalid argument '-mcmodel=large' not allowed with '-fpic'