Let Clang handle compiler optimizations

We no longer need to do anything different from the default.

Fixes #189.

Author: jrprice

src/core/Program.cpp

@@ -282,17 +282,9 @@ bool Program::build(const char *options, list<Header> headers)
   }
   args.push_back(cl_ext.c_str());
 
-  // Disable Clang's optimizations.
-  // We will manually run optimization passes and legalize the IR later.
-  args.push_back("-O0");
-
-  bool optimize = true;
+  bool defaultOptimization = true;
   const char *clstd = NULL;
 
-  // Disable optimizations by default if in interactive mode
-  if (checkEnv("OCLGRIND_INTERACTIVE"))
-    optimize = false;
-
   // Add OpenCL build options
   const char *mainOptions = options;
   const char *extraOptions = getenv("OCLGRIND_BUILD_OPTIONS");
@@ -320,15 +312,9 @@ bool Program::build(const char *options, list<Header> headers)
         strcmp(opt, "-cl-unsafe-math-optimizations") != 0)
     {
       // Check for optimization flags
-      if (strcmp(opt, "-O0") == 0 || strcmp(opt, "-cl-opt-disable") == 0)
+      if (strncmp(opt, "-O", 2) == 0 || strcmp(opt, "-cl-opt-disable") == 0)
       {
-        optimize = false;
-        continue;
-      }
-      else if (strncmp(opt, "-O", 2) == 0)
-      {
-        optimize = true;
-        continue;
+        defaultOptimization = false;
       }
 
       // Clang no longer supports -cl-no-signed-zeros
@@ -346,6 +332,16 @@ bool Program::build(const char *options, list<Header> headers)
     }
   }
 
+  if (defaultOptimization)
+  {
+    // Disable optimizations by default if in interactive mode
+    if (checkEnv("OCLGRIND_INTERACTIVE"))
+      args.push_back("-O0");
+    // Otherwise, default to optimizing for size
+    else
+      args.push_back("-Oz");
+  }
+
   if (!clstd)
   {
     clstd = "-cl-std=CL1.2";
@@ -495,29 +491,6 @@ bool Program::build(const char *options, list<Header> headers)
       stripDebugIntrinsics();
     }
 
-    // Run optimizations on module
-    if (optimize)
-    {
-      // Initialize pass managers
-      llvm::legacy::PassManager modulePasses;
-      llvm::legacy::FunctionPassManager functionPasses(m_module.get());
-
-      // Populate pass managers with -Oz
-      llvm::PassManagerBuilder builder;
-      builder.OptLevel = 2;
-      builder.SizeLevel = 2;
-      builder.populateModulePassManager(modulePasses);
-      builder.populateFunctionPassManager(functionPasses);
-
-      // Run passes
-      functionPasses.doInitialization();
-      llvm::Module::iterator fItr;
-      for (fItr = m_module->begin(); fItr != m_module->end(); fItr++)
-        functionPasses.run(*fItr);
-      functionPasses.doFinalization();
-      modulePasses.run(*m_module);
-    }
-
     removeLValueLoads();
 
     allocateProgramScopeVars();