instead of making codegen try to know about all of the builtins to generate

constants for them, just use the constant evaluator to do the job.  This
also fixes crashes on 'unknown constant builtins'.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@57155 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGExprConstant.cpp b/lib/CodeGen/CGExprConstant.cpp
index e0c39c9cbac6885f0f640ce11898e5c69cf898c7..50f0d122405ff7d06ff4991c3b1a2a12810b7a03 100644 (file)
--- a/lib/CodeGen/CGExprConstant.cpp
+++ b/lib/CodeGen/CGExprConstant.cpp
@@ -14,6 +14,7 @@
 #include "CodeGenFunction.h"
 #include "CodeGenModule.h"
 #include "CGObjCRuntime.h"
+#include "clang/AST/APValue.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/AST/StmtVisitor.h"
 #include "llvm/Constants.h"
@@ -608,14 +609,13 @@ public:
   }
 
   llvm::Constant *VisitCallExpr(const CallExpr *E) {
-    if (const ImplicitCastExpr *IcExpr = 
-        dyn_cast<const ImplicitCastExpr>(E->getCallee()))
-      if (const DeclRefExpr *DRExpr = 
-          dyn_cast<const DeclRefExpr>(IcExpr->getSubExpr()))
-        if (const FunctionDecl *FDecl = 
-            dyn_cast<const FunctionDecl>(DRExpr->getDecl()))
-          if (unsigned builtinID = FDecl->getIdentifier()->getBuiltinID())
-            return EmitBuiltinExpr(builtinID, E);
+    APValue Result;
+    if (E->tryEvaluate(Result, CGM.getContext())) {
+      if (Result.isInt())
+        return llvm::ConstantInt::get(Result.getInt());
+      if (Result.isFloat())
+        return llvm::ConstantFP::get(Result.getFloat());
+    }
 
     CGM.ErrorUnsupported(E, "constant call expression");
     return llvm::Constant::getNullValue(ConvertType(E->getType()));
@@ -818,21 +818,6 @@ public:
     llvm::Type *Ty = llvm::PointerType::getUnqual(ConvertType(E->getType()));
     return llvm::UndefValue::get(Ty);
   }
-
-  llvm::Constant *EmitBuiltinExpr(unsigned BuiltinID, const CallExpr *E)
-  {
-    switch (BuiltinID) {
-    default:
-      CGM.ErrorUnsupported(E, "constant builtin function");
-      return 0;
-    case Builtin::BI__builtin_huge_valf: {
-      const llvm::fltSemantics &Sem =
-      CGM.getContext().getFloatTypeSemantics(E->getType());
-      return llvm::ConstantFP::get(llvm::APFloat::getInf(Sem));
-    }        
-    }
-  }
-    
 };
   
 }  // end anonymous namespace.