Fix handling of invalid -O options.

We were checking the value after truncating it to a bitfield.

Thanks to Yunzhong Gao for noticing it.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@224378 91177308-0d34-0410-b5e6-96231b3b80d8

include/clang/Frontend/CodeGenOptions.def

@@ -87,7 +87,7 @@ CODEGENOPT(NoZeroInitializedInBSS , 1, 0) ///< -fno-zero-initialized-in-bss.
 ENUM_CODEGENOPT(ObjCDispatchMethod, ObjCDispatchMethodKind, 2, Legacy) 
 CODEGENOPT(OmitLeafFramePointer , 1, 0) ///< Set when -momit-leaf-frame-pointer is
                                         ///< enabled.
-VALUE_CODEGENOPT(OptimizationLevel, 3, 0) ///< The -O[0-4] option specified.
+VALUE_CODEGENOPT(OptimizationLevel, 2, 0) ///< The -O[0-3] option specified.
 VALUE_CODEGENOPT(OptimizeSize, 2, 0) ///< If -Os (==1) or -Oz (==2) is specified.
 
 CODEGENOPT(ProfileInstrGenerate , 1, 0) ///< Instrument code to generate

lib/Frontend/CompilerInvocation.cpp

@@ -330,15 +330,17 @@ static bool ParseCodeGenArgs(CodeGenOptions &Opts, ArgList &Args, InputKind IK,
   using namespace options;
   bool Success = true;
 
-  Opts.OptimizationLevel = getOptimizationLevel(Args, IK, Diags);
+  unsigned OptimizationLevel = getOptimizationLevel(Args, IK, Diags);
   // TODO: This could be done in Driver
   unsigned MaxOptLevel = 3;
-  if (Opts.OptimizationLevel > MaxOptLevel) {
-    // If the optimization level is not supported, fall back on the default optimization
+  if (OptimizationLevel > MaxOptLevel) {
+    // If the optimization level is not supported, fall back on the default
+    // optimization
     Diags.Report(diag::warn_drv_optimization_value)
         << Args.getLastArg(OPT_O)->getAsString(Args) << "-O" << MaxOptLevel;
-    Opts.OptimizationLevel = MaxOptLevel;
+    OptimizationLevel = MaxOptLevel;
   }
+  Opts.OptimizationLevel = OptimizationLevel;
 
   // We must always run at least the always inlining pass.
   Opts.setInlining(

test/Frontend/invalid-o-level.c

@@ -1,4 +1,5 @@
-// RUN: %clang_cc1 %s -O900 -o /dev/null 2> %t.log
-// RUN: FileCheck %s -input-file=%t.log
+// RUN: %clang_cc1 %s -O900 -o /dev/null 2>&1 | FileCheck %s
 
-// CHECK: warning: optimization level '-O900' is not supported; using '-O3' instead
+// RUN: %clang_cc1 %s -O8 -o /dev/null 2>&1 | FileCheck %s
+
+// CHECK: warning: optimization level '-O{{.*}}' is not supported; using '-O3' instead