allow omission of location in reductions

There is code in here for omission of location and data in reductions.
Unfortunately we cannot enable the omission of data unless we make changes to
the backtracking. In the current implementation we push the token data with an
mcopy from the data in the token.

1 files changed, 108 insertions, 10 deletions

diff --git a/src/reduce.cc b/src/reduce.cc
index fc6ef4b4..7088e3ed 100644
--- a/src/reduce.cc
+++ b/src/reduce.cc
@@ -50,11 +50,17 @@ void Compiler::writeCommitStub()
 		"}\n"
 		"\n"
 		"long commit_union_sz( int reducer ) { return 0; }\n"
+		"void init_need() {}\n"
+		"int reducer_need_tok( program_t *prg, "
+				"struct pda_run *pda_run, int id ) { return COLM_RN_BOTH; }\n"
+		"int reducer_need_ign( program_t *prg, "
+				"struct pda_run *pda_run ) { return COLM_RN_BOTH; }\n"
 		"\n";
 	;
 }
 
-void Compiler::loadRefs( Production *production, const ReduceTextItemList &list )
+void Compiler::loadRefs( Reduction *reduction, Production *production,
+		const ReduceTextItemList &list )
 {
 	ObjectDef *objectDef = production->prodName->objectDef;
 	Vector<ProdEl*> rhsUsed;
@@ -107,7 +113,8 @@ void Compiler::loadRefs( Production *production, const ReduceTextItemList &list
 	}
 
 	/*
-	 * In the first pass we 
+	 * In the first pass we load using a parse tree cursor. This is for
+	 * nonterms.
 	 */
 	bool useCursor = false;
 	for ( Vector<ProdEl*>::Iter rhs = rhsUsed; rhs.lte(); rhs++ ) {
@@ -153,6 +160,10 @@ void Compiler::loadRefs( Production *production, const ReduceTextItemList &list
 		}
 	}
 
+	/* In the second pass we load using a tree cursor. This is for token data
+	 * and locations.
+	 */
+
 	useCursor = false;
 	for ( Vector<ProdEl*>::Iter rhs = rhsUsed; rhs.lte(); rhs++ ) {
 		if ( *rhs != 0 && (*rhs)->production == production &&
@@ -180,20 +191,23 @@ void Compiler::loadRefs( Production *production, const ReduceTextItemList &list
 		Vector<ProdEl*>::Iter loc = locUsed;
 		
 		for ( ; rhs.lte(); rhs++, loc++ ) {
-			ProdEl *prodEl = *rhs;
-			if ( prodEl != 0 ) {
-				while ( cursorPos < rhs.pos() ) {
-					*outStream <<
-						"	_tree_cursor = _tree_cursor->next;\n";
-					cursorPos += 1;
-				}
 
+			ProdEl *prodEl = *rhs;
 
+			if ( prodEl != 0 ) {
 				if ( prodEl->production == production ) {
 					if ( prodEl->langEl->type == LangEl::Term ) {
+
+			while ( cursorPos < rhs.pos() ) {
+				*outStream <<
+					"	_tree_cursor = _tree_cursor->next;\n";
+				cursorPos += 1;
+			}
 						*outStream <<
 							"	colm_data *_rhs" << rhs.pos() << " = "
 								"_tree_cursor->tree->tokdata;\n";
+
+						reduction->needData[prodEl->langEl->id] = true;
 					}
 				}
 
@@ -202,9 +216,18 @@ void Compiler::loadRefs( Production *production, const ReduceTextItemList &list
 			ProdEl *locEl = *loc;
 			if ( locEl != 0 ) {
 				if ( locEl->production == production ) {
+
+			while ( cursorPos < rhs.pos() ) {
+				*outStream <<
+					"	_tree_cursor = _tree_cursor->next;\n";
+				cursorPos += 1;
+			}
+
 					*outStream <<
 						"	colm_location *_loc" << loc.pos() << " = "
 							"colm_find_location( prg, _tree_cursor->tree );\n";
+
+					reduction->needLoc[locEl->langEl->id] = true;
 				}
 			}
 		}
@@ -300,6 +323,78 @@ struct CmpReduceAction
 	}
 };
 
+void Compiler::initReductionNeeds( Reduction *reduction )
+{
+	reduction->needData = new bool[nextLelId];
+	reduction->needLoc = new bool[nextLelId];
+	memset( reduction->needData, 0, sizeof(bool)*nextLelId );
+	memset( reduction->needLoc, 0, sizeof(bool)*nextLelId );
+}
+
+void Compiler::writeNeeds()
+{
+	*outStream <<
+		"struct reduction_info\n"
+		"{\n"
+		"	unsigned char need_data[" << nextLelId << "];\n"
+		"	unsigned char need_loc[" << nextLelId << "];\n"
+		"};\n"
+		"\n";
+
+	*outStream <<
+		"struct reduction_info ri[" << rootNamespace->reductions.length() + 1 << "];\n"
+		"\n";
+
+	*outStream <<
+		"extern \"C\" void init_need()\n"
+		"{\n";
+	
+	for ( ReductionVect::Iter r = rootNamespace->reductions; r.lte(); r++ ) {
+		Reduction *reduction = *r;
+		*outStream <<
+			"	memset( ri[" << reduction->id << "]"
+					".need_data, 0, sizeof(unsigned char) * " << nextLelId << " );\n"
+			"	memset( ri[" << reduction->id << "]"
+					".need_loc, 0, sizeof(unsigned char) * " << nextLelId << " );\n";
+
+		for ( int i = 0; i < nextLelId; i++ ) {
+			if ( reduction->needData[i] ) {
+				*outStream <<
+					"	ri[" << reduction->id << "].need_data[" << i << "] = COLM_RN_DATA;\n";
+			}
+
+			if ( reduction->needLoc[i] ) {
+				*outStream <<
+					"	ri[" << reduction->id << "].need_loc[" << i << "] = COLM_RN_LOC;\n";
+			}
+		}
+	}
+
+	*outStream <<
+		"}\n";
+
+	*outStream <<
+		"extern \"C\" int reducer_need_tok( program_t *prg, "
+				"struct pda_run *pda_run, int id )\n"
+		"{\n"
+		"	if ( pda_run->reducer > 0 ) {\n"
+		/* Note we are forcing the reducer need for data. Enabling requires finding
+		 * a solution for backtracking push. */
+		"		return COLM_RN_DATA | ri[pda_run->reducer].need_data[id] | \n"
+		"			ri[pda_run->reducer].need_loc[id];\n"
+		"	}\n"
+		"	return COLM_RN_BOTH;\n"
+		"}\n"
+		"\n"
+		"extern \"C\" int reducer_need_ign( program_t *prg, struct pda_run *pda_run )\n"
+		"{\n"
+		// Using this requires finding a solution for backtracking push back.
+		//"	if ( pda_run->reducer > 0 )\n"
+		//"		return COLM_RN_NEITHER;\n"
+		"	return COLM_RN_BOTH;\n"
+		"}\n";
+}
+
 void Compiler::writeCommit()
 {
 	*outStream <<
@@ -386,6 +481,7 @@ void Compiler::writeCommit()
 
 	for ( ReductionVect::Iter r = rootNamespace->reductions; r.lte(); r++ ) {
 		Reduction *reduction = *r;
+		initReductionNeeds( reduction );
 
 		*outStream <<
 			"void " << reduction->name << "::commit_reduce_forward( program_t *prg, \n"
@@ -463,7 +559,7 @@ void Compiler::writeCommit()
 			*outStream << 
 				"			if ( kid->tree->prod_num == " << prodNum << " ) {\n";
 
-			loadRefs( action->production, action->itemList );
+			loadRefs( reduction, action->production, action->itemList );
 
 			*outStream <<
 				"#line " << action->loc.line << "\"" << action->loc.fileName << "\"\n";
@@ -496,4 +592,6 @@ void Compiler::writeCommit()
 			"}\n"
 			"\n";
 	}
+
+	writeNeeds();
 }