From 47b98470eb983227184cc61cdebd1d759b47278a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Marjam=C3=A4ki?= <daniel.marjamaki@gmail.com>
Date: Tue, 19 Nov 2013 18:07:12 +0100
Subject: [PATCH] Tokenizer: Simplify float casts of integer constants

---
 lib/tokenize.cpp      | 14 ++++++++++++++
 lib/tokenize.h        |  5 +++++
 test/testtokenize.cpp |  8 ++++++++
 3 files changed, 27 insertions(+)

diff --git a/lib/tokenize.cpp b/lib/tokenize.cpp
index 6ce67b1ac..0aa08544e 100644
--- a/lib/tokenize.cpp
+++ b/lib/tokenize.cpp
@@ -1994,6 +1994,9 @@ bool Tokenizer::tokenize(std::istream &code,
 
     simplifyVariableMultipleAssign();
 
+    // Simplify float casts (float)1 => 1.0
+    simplifyFloatCasts();
+
     // Remove redundant parentheses
     simplifyRedundantParentheses();
     for (Token *tok = list.front(); tok; tok = tok->next())
@@ -4789,6 +4792,17 @@ void Tokenizer::simplifyUndefinedSizeArray()
     }
 }
 
+void Tokenizer::simplifyFloatCasts()
+{
+    for (Token *tok = list.front(); tok; tok = tok->next()) {
+        if (Token::Match(tok->next(), "( float|double ) %num%") && MathLib::isInt(tok->strAt(4))) {
+            tok->deleteNext(3);
+            tok = tok->next();
+            tok->str(tok->str() + ".0");
+        }
+    }
+}
+
 void Tokenizer::simplifyCasts()
 {
     for (Token *tok = list.front(); tok; tok = tok->next()) {
diff --git a/lib/tokenize.h b/lib/tokenize.h
index a98bc8e1b..295d8ac06 100644
--- a/lib/tokenize.h
+++ b/lib/tokenize.h
@@ -325,6 +325,11 @@ public:
      */
     void simplifyTypedef();
 
+    /**
+     * Simplify float casts (float)1 => 1.0
+     */
+    void simplifyFloatCasts();
+
     /**
      * Simplify casts
      */
diff --git a/test/testtokenize.cpp b/test/testtokenize.cpp
index 87f84ad2d..3ff340586 100644
--- a/test/testtokenize.cpp
+++ b/test/testtokenize.cpp
@@ -97,6 +97,8 @@ private:
         TEST_CASE(removeCast12);
         TEST_CASE(removeCast13);
 
+        TEST_CASE(simplifyFloatCasts); // float casting a integer
+
         TEST_CASE(inlineasm);
 
         TEST_CASE(ifAddBraces1);
@@ -1123,6 +1125,12 @@ private:
                            tokenizeAndStringify("; float angle = (float) +tilt;", true));
     }
 
+    void simplifyFloatCasts() { // float casting integers
+        ASSERT_EQUALS("a = 1.0 ;", tokenizeAndStringify("a = (float)1;"));
+        ASSERT_EQUALS("a = 1.0 ;", tokenizeAndStringify("a = ((float)1);"));
+        ASSERT_EQUALS("a = 291.0 ;", tokenizeAndStringify("a = ((float)0x123);"));
+    }
+
     void inlineasm() {
         ASSERT_EQUALS("asm ( \"mov ax , bx\" ) ;", tokenizeAndStringify("asm { mov ax,bx };"));
         ASSERT_EQUALS("asm ( \"mov ax , bx\" ) ;", tokenizeAndStringify("_asm { mov ax,bx };"));