Add C binding for AllocaInst::getAllocatedType

[deadalnix]

Summary

Comes with an awesome test.

Depends on D16912

[deadalnix]

Rebase on top of D16912

[mehdi_amini]

LGTM

include/llvm-c/Core.h

  */
 LLVMBasicBlockRef LLVMGetSwitchDefaultDest(LLVMValueRef SwitchInstr);
 
 /**
  * @}
  */
 
 /**
+ * @defgroup LLVMCCoreValueInstructionAlloca Allocas
+ *
+ * Functions in this group only apply to instructions that map to
+ * llvm::Alloca instances.
+ *
+ * @{
+ */
+
+/**
+ * Obtain the type that is being allocated by the alloca instruction.
+ */
+LLVMTypeRef LLVMGetAllocatedType(LLVMValueRef Alloca);
+
+/**
+ * @}
+ */
+
+/**
  * @defgroup LLVMCCoreValueInstructionPHINode PHI Nodes
  *
  * Functions in this group only apply to instructions that map to
  * llvm::PHINode instances.
  *
  * @{
  */
 

lib/IR/Core.cpp

 }
 
 /*--.. Operations on switch instructions (only) ............................--*/
 
 LLVMBasicBlockRef LLVMGetSwitchDefaultDest(LLVMValueRef Switch) {
   return wrap(unwrap<SwitchInst>(Switch)->getDefaultDest());
 }
 
+/*--.. Operations on alloca instructions (only) ............................--*/
+
+LLVMTypeRef LLVMGetAllocatedType(LLVMValueRef Alloca) {
+  return wrap(unwrap<AllocaInst>(Alloca)->getAllocatedType());
+}
+
 /*--.. Operations on phi nodes .............................................--*/
 
 void LLVMAddIncoming(LLVMValueRef PhiNode, LLVMValueRef *IncomingValues,
                      LLVMBasicBlockRef *IncomingBlocks, unsigned Count) {
   PHINode *PhiVal = unwrap<PHINode>(PhiNode);
   for (unsigned I = 0; I != Count; ++I)
     PhiVal->addIncoming(unwrap(IncomingValues[I]), unwrap(IncomingBlocks[I]));
 }

tools/llvm-c-test/echo.cpp

switch(Op) {
       }
       case LLVMXor: {
         LLVMValueRef LHS = CloneValue(LLVMGetOperand(Src, 0), Builder);
         LLVMValueRef RHS = CloneValue(LLVMGetOperand(Src, 1), Builder);
         Dst = LLVMBuildXor(Builder, LHS, RHS, Name);
         break;
       }
       case LLVMAlloca: {
-        LLVMTypeRef Ty = LLVMGetElementType(LLVMTypeOf(Src));
+        LLVMContextRef Ctx = LLVMGetModuleContext(get_module(Builder));
+        LLVMTypeRef Ty = clone_type(LLVMGetAllocatedType(Src), Ctx);
         Dst = LLVMBuildAlloca(Builder, Ty, Name);
         break;
       }
       case LLVMCall: {
         int ArgCount = LLVMGetNumOperands(Src) - 1;
         SmallVector<LLVMValueRef, 8> Args;
         for (int i = 0; i < ArgCount; i++)
           Args.push_back(CloneValue(LLVMGetOperand(Src, i), Builder));