added some pointer arithmetic optimizations but not stable yet so not

[fw/sdcc] / src / SDCCptropt.c

diff --git a/src/SDCCptropt.c b/src/SDCCptropt.c
index 1db821d69461db02fb32afc0944fd9ba9c378880..3660bb7f1631b88a4edf09fa6a3a35ee36f0425f 100644 (file)
--- a/src/SDCCptropt.c
+++ b/src/SDCCptropt.c
@@ -173,7 +173,6 @@ static int pattern2 (iCode *sic)
        pgs->next = sh;
        sh->prev = pgs;
        return 1;
-       return 1;
 }
 
 /*-----------------------------------------------------------------------*/
@@ -186,3 +185,36 @@ ptrPostIncDecOpt (iCode * sic)
        if (pattern1(sic)) return ;
        pattern2(sic);
 }
+
+/*-----------------------------------------------------------------------*/
+/* addPattern1 - transform addition to pointer of variables              */
+/*-----------------------------------------------------------------------*/
+static int addPattern1(iCode *ic)
+{
+       iCode *dic;
+       operand *tmp;
+       /* transform :
+          iTempAA = iTempBB + iTempCC
+          iTempDD = iTempAA + CONST
+          to
+          iTempAA = iTempBB + CONST
+          iTempDD = iTempAA + iTempCC
+       */
+       if (!isOperandLiteral(IC_RIGHT(ic))) return 0;
+       if ((dic=findBackwardDef(IC_LEFT(ic),ic->prev)) == NULL) return 0;
+       if (bitVectnBitsOn(OP_SYMBOL(IC_RESULT(dic))->uses) > 1) return 0;
+       if (dic->op != '+') return 0;
+       tmp = IC_RIGHT(ic);
+       IC_RIGHT(ic) = IC_RIGHT(dic);
+       IC_RIGHT(dic) = tmp;
+       return 1;
+}
+
+/*-----------------------------------------------------------------------*/
+/* ptrAddition - optimize pointer additions                              */
+/*-----------------------------------------------------------------------*/
+int ptrAddition (iCode *sic)
+{
+       if (addPattern1(sic)) return 1;
+       return 0;
+}