[GC] Verify-pass void vararg functions in gc.statepoint

With the appropriate Verifier changes, exactracting the result out of a
statepoint wrapping a vararg function crashes. However, a void vararg
function works fine: commit this first step.

Differential Revision: http://reviews.llvm.org/D7071

llvm-svn: 226599

1 files changed, 13 insertions, 5 deletions

diff --git a/llvm/lib/IR/Verifier.cpp b/llvm/lib/IR/Verifier.cpp
index f0a149354ae..c95018d1772 100644
--- a/llvm/lib/IR/Verifier.cpp
+++ b/llvm/lib/IR/Verifier.cpp
@@ -2639,8 +2639,6 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
             "gc.statepoint callee must be of function pointer type",
             &CI, Target);
     FunctionType *TargetFuncType = cast<FunctionType>(PT->getElementType());
-    Assert1(!TargetFuncType->isVarArg(),
-            "gc.statepoint support for var arg functions not implemented", &CI);
 
     const Value *NumCallArgsV = CI.getArgOperand(1);
     Assert1(isa<ConstantInt>(NumCallArgsV),
@@ -2650,8 +2648,18 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
     Assert1(NumCallArgs >= 0,
             "gc.statepoint number of arguments to underlying call "
             "must be positive", &CI);
-    Assert1(NumCallArgs == (int)TargetFuncType->getNumParams(),
-            "gc.statepoint mismatch in number of call args", &CI);
+    const int NumParams = (int)TargetFuncType->getNumParams();
+    if (TargetFuncType->isVarArg()) {
+      Assert1(NumCallArgs >= NumParams,
+              "gc.statepoint mismatch in number of vararg call args", &CI);
+
+      // TODO: Remove this limitation
+      Assert1(TargetFuncType->getReturnType()->isVoidTy(),
+              "gc.statepoint doesn't support wrapping non-void "
+              "vararg functions yet", &CI);
+    } else
+      Assert1(NumCallArgs == NumParams,
+              "gc.statepoint mismatch in number of call args", &CI);
 
     const Value *Unused = CI.getArgOperand(2);
     Assert1(isa<ConstantInt>(Unused) &&
@@ -2660,7 +2668,7 @@ void Verifier::visitIntrinsicFunctionCall(Intrinsic::ID ID, CallInst &CI) {
 
     // Verify that the types of the call parameter arguments match
     // the type of the wrapped callee.
-    for (int i = 0; i < NumCallArgs; i++) {
+    for (int i = 0; i < NumParams; i++) {
       Type *ParamType = TargetFuncType->getParamType(i);
       Type *ArgType = CI.getArgOperand(3+i)->getType();
       Assert1(ArgType == ParamType,