enable custoim safe pass in order to remove bitcast instructions

Change-Id: I65240f5b09205bcc3f2c2bac9c77d3d1c853e9d4

Author: traoux1

IGC/Compiler/CISACodeGen/ShaderCodeGen.cpp

@@ -1142,9 +1142,9 @@ void OptimizeIR(CodeGenContext* pContext)
         mpm.add(new BreakConstantExpr());
         mpm.add(new IGCConstProp(!pContext->m_DriverInfo.SupportsPreciseMath()));
 
+        mpm.add(new CustomSafeOptPass());
         if(!pContext->m_DriverInfo.WADisableCustomPass())
         {
-            mpm.add(new CustomSafeOptPass());
             mpm.add(new CustomUnsafeOptPass());
         }
 
@@ -1300,9 +1300,9 @@ void OptimizeIR(CodeGenContext* pContext)
                 mpm.add(CreateEarlyOutPatternsPass());
                 mpm.add(createBlendToDiscardPass());
             }
+            mpm.add(new CustomSafeOptPass());
             if (!pContext->m_DriverInfo.WADisableCustomPass())
             {
-                mpm.add(new CustomSafeOptPass());
                 mpm.add(new CustomUnsafeOptPass());
             }
         }

IGC/Compiler/CustomSafeOptPass.cpp

@@ -186,7 +186,7 @@ void CustomSafeOptPass::visitAllocaInst(AllocaInst &I)
         if (GetElementPtrInst *pGEP = llvm::dyn_cast<GetElementPtrInst>(*it))
         {
             ConstantInt *C0 = dyn_cast<ConstantInt>(pGEP->getOperand(1));
-            if (!C0 || !C0->isZero())
+            if (!C0 || !C0->isZero() || pGEP->getNumOperands() != 3)
             {
                 return;
             }