Added RA heuristic to enable fail-safe RA with limited

addr taken spill size.

Change-Id: I101f42759c4a133d72ddaf7f2f7523d8037eb4de

Author: kychendev

visa/FlowGraph.h

@@ -1137,7 +1137,6 @@ class G4_Kernel
     const char* name;
     unsigned numRegTotal;
     unsigned int simdSize;
-    bool hasAddrTaken;
     Options *m_options;
 
 	RA_Type RAType;
@@ -1164,6 +1163,8 @@ class G4_Kernel
     uint32_t bank_ok_num;
     uint32_t bank_bad_num;
 
+	uint32_t maxAddrTakenSize;
+
     unsigned int callerSaveLastGRF;
 
 public:
@@ -1189,7 +1190,6 @@ class G4_Kernel
         numRegTotal = UNDEFINED_VAL;
         name = NULL;
         simdSize = 0;
-        hasAddrTaken = false;
         kernelDbgInfo = nullptr;
         if (options->getOption(vISAOptions::vISA_ReRAPostSchedule) ||
             options->getOption(vISAOptions::vISA_GetFreeGRFInfo))
@@ -1203,6 +1203,7 @@ class G4_Kernel
 
         unsigned int totalGRFs = options->getuInt32Option(vISA_TotalGRFNum);
         callerSaveLastGRF = ((totalGRFs - 8) / 2) - 1;
+		maxAddrTakenSize = 0;
     }
 
     ~G4_Kernel();
@@ -1264,8 +1265,11 @@ class G4_Kernel
     void calculateSimdSize();
     unsigned int getSimdSize() { return simdSize; }
 
-    void setHasAddrTaken(bool val) { hasAddrTaken = val; }
-    bool getHasAddrTaken() { return hasAddrTaken;  }
+	void setMaxAddrTakenSize(uint32_t val) { 
+		if (val > maxAddrTakenSize) 
+			maxAddrTakenSize = val; 
+	}
+	uint32_t getMaxAddrTakenSize() { return maxAddrTakenSize; }
 
     void setNumRegTotal(unsigned num)     {numRegTotal = num;}
     void setName(const char* n)                  {name = n;}

visa/GraphColor.cpp

@@ -47,6 +47,7 @@ using namespace std;
 using namespace vISA;
 
 #define FAIL_SAFE_RA_LIMIT 3
+#define ADDR_TAKE_SIZE_LIMIT 256
 
 #define MIN(x,y)	(((x)<(y))? (x):(y))
 #define MAX(x,y)	(((x)<(y))? (y):(x))
@@ -9689,7 +9690,7 @@ int GlobalRA::coloringRegAlloc()
         }
 
         bool allowAddrTaken = builder.getOption(vISA_FastSpill) ||
-            !kernel.getHasAddrTaken();
+            (kernel.getMaxAddrTakenSize() <= ADDR_TAKE_SIZE_LIMIT);
         bool reserveSpillReg = false;
         if (builder.getOption(vISA_FailSafeRA) &&
             kernel.getOptions()->getTarget() == VISA_3D &&

visa/VISAKernelImpl.cpp

@@ -1560,13 +1560,16 @@ int VISAKernelImpl::CreateVISAAddressOfOperandGeneric(VISA_VectorOpnd *&cisa_opn
         }
 #endif
         // set up to the top level dcl to be addressed
-        src0Dcl->setAddressed();
-        m_kernel->setHasAddrTaken(true);
-        G4_Declare *parentDcl = src0Dcl->getAliasDeclare();
-        while( parentDcl ){
+		src0Dcl->setAddressed();
+        G4_Declare *parentDcl = src0Dcl->getAliasDeclare(); 
+		G4_Declare *topDcl = src0Dcl;
+        while( parentDcl )
+		{
             parentDcl->setAddressed();
+			topDcl = parentDcl;
             parentDcl = parentDcl->getAliasDeclare();
         }
+		m_kernel->setMaxAddrTakenSize(topDcl->getByteSize());
         cisa_opnd->g4opnd = m_builder->createAddrExp(
             src0Dcl->getRegVar(),
             offset,