Changeset 4676

Timestamp:

Jul 15, 2015, 6:20:38 PM (4 years ago)

Author:

cameron

Message:

Simplify/unify conditional creation of explicit carry summary code and summary phi nodes.

Location:

icGREP/icgrep-devel/icgrep/pablo

Files:

• carry_data.cpp (modified) (1 diff)
• carry_data.h (modified) (1 diff)
• carry_manager.cpp (modified) (2 diffs)
• carry_manager.h (modified) (1 diff)
• pablo_compiler.cpp (modified) (2 diffs)

icGREP/icgrep-devel/icgrep/pablo/carry_data.cpp

@@ -112 +112 @@
     scopeCarryDataBits = nestedframePosition;
     
-    if ((ifDepth > 0) && (scopeCarryDataBits > BLOCK_SIZE)) {
+    if (explicitSummaryRequired()) {
         // Need extra space for the summary variable, always the last
         // entry within an if block.

icGREP/icgrep-devel/icgrep/pablo/carry_data.h

@@ -94 +94 @@
     bool blockHasCarries() const { return scopeCarryDataBits > 0;}
     
-    bool explicitSummaryRequired() const { return scopeCarryDataBits > BLOCK_SIZE;}
-    
-    bool summaryNeededInParentBlock() const {return (ifDepth > 0) && blockHasCarries();}
+    bool explicitSummaryRequired() const { return (ifDepth > 0) && (scopeCarryDataBits > BLOCK_SIZE);}
     
 private:

icGREP/icgrep-devel/icgrep/pablo/carry_manager.cpp

@@ -210 +210 @@
 }
 
-bool CarryManager::summaryNeededInParentBlock(){
-    return mCarryInfo->summaryNeededInParentBlock();
-} 
-
-void CarryManager::addSummaryPhi(BasicBlock * ifEntryBlock, BasicBlock * ifBodyFinalBlock) {
+void CarryManager::addSummaryPhiIfNeeded(BasicBlock * ifEntryBlock, BasicBlock * ifBodyFinalBlock) {
+    if ((mCarryInfo->getIfDepth() <= 1) || !mCarryInfo->blockHasCarries()){
+        // For ifDepth == 1, the parent does not need a summary as it is not itself within an if.
+        // Therefore, it doesn't need access to this block's summary in building its own.
+        return;
+    }
     const unsigned carrySummaryIndex = mCurrentScopeIndex + mCarryInfo->summaryCarryDataIndex();
     PHINode * summary_phi = mBuilder->CreatePHI(mBitBlockType, 2, "summary");
@@ -222 +223 @@
 }
 
-void CarryManager::generateCarryOutSummaryCode() {
+void CarryManager::generateCarryOutSummaryCodeIfNeeded() {
+    
+    if (!mCarryInfo->explicitSummaryRequired()) {
+        // An explicit summary may not be required, if there is a single carry
+        // operation within the block, or the carries are packed and all carry
+        // bits fit within a single pack.
+        return;
+    }
     
     const unsigned carrySummaryIndex = mCurrentScopeIndex + mCarryInfo->summaryCarryDataIndex();
-    
-    if (mCarryInfo->getScopeCarryDataSize() == 1) {
-        // If scopeCarryDataSize == 1, then we have one pack which serves as
-        // the summary.   It should already be stored.   
-        return;
-    }
     
     Value * carry_summary = mZeroInitializer;

icGREP/icgrep-devel/icgrep/pablo/carry_manager.h

@@ -76 +76 @@
     Value * getCarrySummaryExpr();
     
-    void generateCarryOutSummaryCode();
+    void generateCarryOutSummaryCodeIfNeeded();
     
-    bool summaryNeededInParentBlock();
-    
-    void addSummaryPhi(BasicBlock * ifEntryBlock, BasicBlock * ifBodyFinalBlock);
+    void addSummaryPhiIfNeeded(BasicBlock * ifEntryBlock, BasicBlock * ifBodyFinalBlock);
     
     /* Methods for load/store of carries for non-while blocks. */

icGREP/icgrep-devel/icgrep/pablo/pablo_compiler.cpp

@@ -462 +462 @@
     --mIfDepth;
     if (mCarryManager->blockHasCarries()) {
-        mCarryManager->generateCarryOutSummaryCode();
+        mCarryManager->generateCarryOutSummaryCodeIfNeeded();
     }
     BasicBlock * ifBodyFinalBlock = mBuilder->GetInsertBlock();
@@ -478 +478 @@
     }
     // Create the phi Node for the summary variable, if needed.
-    if (mCarryManager->summaryNeededInParentBlock()) {
-        mCarryManager->addSummaryPhi(ifEntryBlock, ifBodyFinalBlock);
-    }
+    mCarryManager->addSummaryPhiIfNeeded(ifEntryBlock, ifBodyFinalBlock);
     mCarryManager->leaveScope();
 }