IGC constant folding works only on internal intrinsics

ConstantFolderIGC is introduced to assure availibility of constant folding functionality for IGC clients. The constant folder give a hand for the instructions that are not constant folded by llvm passes or its folder.

Change-Id: I6558ac720b8ed729d4c580f3c55618404a7d8d49

Author: krystian-andrzejewski

IGC/AdaptorOCL/DriverInfoOCL.hpp

@@ -38,8 +38,6 @@ namespace TC
 
         bool SupportsIEEEMinMax() const override { return true; }
 
-        bool SupportsPreciseMath() const override { return true; }
-
         bool NeedCheckContractionAllowed() const override { return true; }
 
         bool NeedI64BitDivRem() const override { return true; }

IGC/Compiler/CISACodeGen/DriverInfo.hpp

@@ -115,9 +115,6 @@ namespace IGC
         /// API supports IEEE min/max
         virtual bool SupportsIEEEMinMax() const { return false; }
 
-        /// Supports precise math
-        virtual bool SupportsPreciseMath() const { return false; }
-
         virtual bool NeedCountSROA() const { return false; }
 
         /// Can we always contract mul and add

IGC/Compiler/CISACodeGen/ShaderCodeGen.cpp

@@ -1411,7 +1411,7 @@ void OptimizeIR(CodeGenContext* const pContext)
         }
 
         mpm.add(new BreakConstantExpr());
-        mpm.add(new IGCConstProp(!pContext->m_DriverInfo.SupportsPreciseMath()));
+        mpm.add(new IGCConstProp());
 
         mpm.add(new CustomSafeOptPass());
         if (!pContext->m_DriverInfo.WADisableCustomPass())
@@ -1552,8 +1552,7 @@ void OptimizeIR(CodeGenContext* const pContext)
                 mpm.add(llvm::createAggressiveDCEPass());
 
             mpm.add(new BreakConstantExpr());
-            mpm.add(new IGCConstProp(!pContext->m_DriverInfo.SupportsPreciseMath(),
-                IGC_IS_FLAG_ENABLED(EnableSimplifyGEP)));
+            mpm.add(new IGCConstProp(IGC_IS_FLAG_ENABLED(EnableSimplifyGEP)));
 
             if (IGC_IS_FLAG_DISABLED(DisableImmConstantOpt))
             {