From: Ulya Trofimovich <skvadrik@gmail.com>
Date: Tue, 27 Sep 2016 14:11:05 +0000 (+0100)
Subject: Use explicit constant 'ZERO_TAGS' instead of 0.
X-Git-Tag: 1.0~39^2~276
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=5cf0a227c58204ddfbe879af5ef72990346533ad;p=re2c

Use explicit constant 'ZERO_TAGS' instead of 0.
---

diff --git a/re2c/src/codegen/bitmap.cc b/re2c/src/codegen/bitmap.cc
index aa8c841d..b4c3e21d 100644
--- a/re2c/src/codegen/bitmap.cc
+++ b/re2c/src/codegen/bitmap.cc
@@ -160,8 +160,8 @@ bool matches(const Span * b1, uint32_t n1, const State * s1, const Span * b2, ui
 		// might go to the same state, but have different tag sets
 		if (lb1 != lb2
 			|| b1->ub != b2->ub
-			|| b1->tags != 0
-			|| b2->tags != 0)
+			|| b1->tags != ZERO_TAGS
+			|| b2->tags != ZERO_TAGS)
 		{
 			return false;
 		}
diff --git a/re2c/src/codegen/emit_action.cc b/re2c/src/codegen/emit_action.cc
index bc42965b..a29ca408 100644
--- a/re2c/src/codegen/emit_action.cc
+++ b/re2c/src/codegen/emit_action.cc
@@ -319,7 +319,7 @@ void genSetState(OutputFile &o, uint32_t ind, uint32_t fillIndex)
 void gen_goto_case(OutputFile &o, uint32_t ind, bool &readCh,
 	const State *to, const DFA &dfa, size_t tags)
 {
-	const bool multiline = readCh || (tags != 0);
+	const bool multiline = readCh || (tags != ZERO_TAGS);
 
 	if (multiline) {
 		o.ws("\n");
@@ -333,7 +333,7 @@ void gen_goto_if(OutputFile &o, uint32_t ind, bool &readCh,
 	const State *to, const DFA &dfa, size_t tags)
 {
 	const int32_t linecount = (readCh && to != NULL)
-		+ (tags != 0)
+		+ (tags != ZERO_TAGS)
 		+ (to != NULL);
 
 	if (linecount > 1) {
@@ -364,7 +364,7 @@ void gen_goto(OutputFile &o, uint32_t ind, bool &readCh,
 
 void gen_settags(OutputFile &o, uint32_t ind, const DFA &dfa, size_t tags)
 {
-	if (tags != 0) {
+	if (tags != ZERO_TAGS) {
 		if (dfa.basetag) {
 			o.wstring(opts->input_api.stmt_dist(ind,
 				dfa.tagpool[tags], dfa.tags));
diff --git a/re2c/src/codegen/go.h b/re2c/src/codegen/go.h
index 1cd15e00..defa6a18 100644
--- a/re2c/src/codegen/go.h
+++ b/re2c/src/codegen/go.h
@@ -6,6 +6,7 @@
 #include <vector>
 
 #include "src/codegen/output.h"
+#include "src/ir/tagpool.h"
 #include "src/util/c99_stdint.h"
 #include "src/util/forbid_copy.h"
 
@@ -33,7 +34,7 @@ struct Case
 	size_t tags;
 
 	void emit(OutputFile &o, uint32_t ind) const;
-	inline Case(): ranges(), to(NULL), tags(0) {}
+	inline Case(): ranges(), to(NULL), tags(ZERO_TAGS) {}
 	FORBID_COPY(Case);
 };
 
@@ -78,7 +79,7 @@ struct Linear
 		const State *to;
 		size_t tags;
 
-		Branch(): cond(NULL), to(NULL), tags(0) {}
+		Branch(): cond(NULL), to(NULL), tags(ZERO_TAGS) {}
 		void init(const Cond *c, const State *s, size_t ts)
 		{
 			cond = c;
diff --git a/re2c/src/codegen/go_construct.cc b/re2c/src/codegen/go_construct.cc
index 0da2b52d..e602e5ea 100644
--- a/re2c/src/codegen/go_construct.cc
+++ b/re2c/src/codegen/go_construct.cc
@@ -186,7 +186,7 @@ Dot::Dot (const Span * sp, uint32_t nsp, const State * s)
 Go::Go ()
 	: nSpans (0)
 	, span (NULL)
-	, tags (0)
+	, tags (ZERO_TAGS)
 	, type (EMPTY)
 	, info ()
 {}
@@ -213,7 +213,7 @@ void Go::init (const State * from)
 
 	bool low_spans_have_tags = false;
 	for (uint32_t i = 0; i < nSpans - hSpans; ++i) {
-		if (span[i].tags != 0) {
+		if (span[i].tags != ZERO_TAGS) {
 			low_spans_have_tags = true;
 			break;
 		}
diff --git a/re2c/src/ir/adfa/prepare.cc b/re2c/src/ir/adfa/prepare.cc
index 92dafc2a..517568ea 100644
--- a/re2c/src/ir/adfa/prepare.cc
+++ b/re2c/src/ir/adfa/prepare.cc
@@ -25,7 +25,7 @@ void DFA::split(State *s)
 	s->go.span = allocate<Span> (1);
 	s->go.span[0].ub = ubChar;
 	s->go.span[0].to = move;
-	s->go.span[0].tags = 0;
+	s->go.span[0].tags = ZERO_TAGS;
 }
 
 static uint32_t merge(Span *x, State *fg, State *bg)
@@ -39,7 +39,7 @@ static uint32_t merge(Span *x, State *fg, State *bg)
 	for (;!(f == fe && b == be);) {
 		if (f->to == b->to && f->tags == b->tags) {
 			x->to = bg;
-			x->tags = 0;
+			x->tags = ZERO_TAGS;
 		} else {
 			x->to = f->to;
 			x->tags = f->tags;
@@ -214,14 +214,14 @@ void DFA::hoist_tags()
 		if (nsp > 0) {
 			Span *sp = s->go.span;
 			const size_t tags0 = sp[0].tags;
-			bool common_tags = tags0 != 0;
+			bool common_tags = tags0 != ZERO_TAGS;
 			for (uint32_t i = 1; common_tags && i < nsp; ++i) {
 				common_tags &= sp[i].tags == tags0;
 			}
 			if (common_tags) {
 				s->go.tags = tags0;
 				for (uint32_t i = 0; i < nsp; ++i) {
-					sp[i].tags = 0;
+					sp[i].tags = ZERO_TAGS;
 				}
 			}
 		}
diff --git a/re2c/src/ir/dfa/determinization.cc b/re2c/src/ir/dfa/determinization.cc
index a3c7f8d5..548ac58c 100644
--- a/re2c/src/ir/dfa/determinization.cc
+++ b/re2c/src/ir/dfa/determinization.cc
@@ -75,7 +75,7 @@ dfa_t::dfa_t(const nfa_t &nfa,
 	bool *mask = new bool[ntags];
 	bool *fin = new bool[nrules];
 
-	clos1.push_back(clos_t(nfa.root, static_cast<size_t>(0)));
+	clos1.push_back(clos_t(nfa.root, ZERO_TAGS));
 	closure(clos1, clos2, ktags, badtags, ntags);
 	find_state(clos2, clospool, tagpool);
 
diff --git a/re2c/src/ir/dfa/dfa.h b/re2c/src/ir/dfa/dfa.h
index a0eda8d4..839df748 100644
--- a/re2c/src/ir/dfa/dfa.h
+++ b/re2c/src/ir/dfa/dfa.h
@@ -28,7 +28,7 @@ struct dfa_state_t
 		: arcs(new size_t[nchars])
 		, tags(new size_t[nchars])
 		, rule(Rule::NONE)
-		, rule_tags(0)
+		, rule_tags(ZERO_TAGS)
 		, fallback(false)
 	{}
 	~dfa_state_t()
diff --git a/re2c/src/ir/dfa/tag_deduplication.cc b/re2c/src/ir/dfa/tag_deduplication.cc
index 9d67a19b..dbba1954 100644
--- a/re2c/src/ir/dfa/tag_deduplication.cc
+++ b/re2c/src/ir/dfa/tag_deduplication.cc
@@ -244,7 +244,7 @@ static void patch_tags(dfa_t &dfa, const size_t *represent)
 static size_t fallback_tags(const dfa_t &dfa)
 {
 	const size_t nstates = dfa.states.size();
-	size_t tags = 0;
+	size_t tags = ZERO_TAGS;
 	for (size_t i = 0; i < nstates; ++i) {
 		const dfa_state_t *s = dfa.states[i];
 		if (s->fallback) { // see note [fallback states]
diff --git a/re2c/src/ir/rule.h b/re2c/src/ir/rule.h
index e6fda6bd..35a3098b 100644
--- a/re2c/src/ir/rule.h
+++ b/re2c/src/ir/rule.h
@@ -6,6 +6,7 @@
 #include <vector>
 
 #include "src/ir/tag.h"
+#include "src/ir/tagpool.h"
 #include "src/parse/code.h"
 #include "src/parse/loc.h"
 #include "src/util/forbid_copy.h"
@@ -46,7 +47,7 @@ struct Rule
 		, ltag(0)
 		, htag(0)
 		, trail(Tag::NONE)
-		, tags(0)
+		, tags(ZERO_TAGS)
 		, shadow()
 	{}
 
diff --git a/re2c/src/ir/tagpool.cc b/re2c/src/ir/tagpool.cc
index fbebe8c6..0f05fe9f 100644
--- a/re2c/src/ir/tagpool.cc
+++ b/re2c/src/ir/tagpool.cc
@@ -1,3 +1,5 @@
+#include <assert.h>
+
 #include "src/ir/tagpool.h"
 #include "src/util/hash32.h"
 
@@ -9,8 +11,8 @@ Tagpool::Tagpool(size_t n)
 	, lookup()
 	, buff(new bool[ntags]())
 {
-	// all-no tag set must have number 0
-	insert(buff);
+	// all-zero tag configuration must have static number zero
+	assert(ZERO_TAGS == insert(buff));
 }
 
 Tagpool::~Tagpool()
@@ -47,7 +49,7 @@ size_t Tagpool::orl(size_t t, size_t o)
 {
 	if (t == o || o == 0) {
 		return t;
-	} else if (t == 0) {
+	} else if (t == ZERO_TAGS) {
 		return o;
 	}
 
@@ -63,8 +65,8 @@ size_t Tagpool::andl(size_t t, size_t a)
 {
 	if (t == a) {
 		return t;
-	} else if (t == 0 || a == 0) {
-		return 0;
+	} else if (t == ZERO_TAGS || a == ZERO_TAGS) {
+		return ZERO_TAGS;
 	}
 
 	const bool *tags = operator[](t);
@@ -77,10 +79,10 @@ size_t Tagpool::andl(size_t t, size_t a)
 
 size_t Tagpool::andlinv(size_t t, size_t a)
 {
-	if (a == 0) {
+	if (a == ZERO_TAGS) {
 		return t;
-	} else if (t == 0 || t == a) {
-		return 0;
+	} else if (t == ZERO_TAGS || t == a) {
+		return ZERO_TAGS;
 	}
 
 	const bool *tags = operator[](t);
diff --git a/re2c/src/ir/tagpool.h b/re2c/src/ir/tagpool.h
index 2dd12b9b..b3ef37d0 100644
--- a/re2c/src/ir/tagpool.h
+++ b/re2c/src/ir/tagpool.h
@@ -10,6 +10,8 @@
 namespace re2c
 {
 
+static const size_t ZERO_TAGS = 0;
+
 struct eqtag_t
 {
 	size_t ntags;