codea: weitere optimierung fuer sub/add

diff --git a/codea/code.bfe b/codea/code.bfe
index e88f2eb2ec87603f03b18a2a432921a2af0cbdd1..654d669ba1afafef1d9a0860c2f28eeca94d4cfb 100644 (file)
--- a/codea/code.bfe
+++ b/codea/code.bfe
@@ -39,6 +39,14 @@ void gen_e_eno(struct treenode *bnode, char *instr)
        printf("\t%s %%%s, %%%s\n", instr, KID_REG(1), KID_REG(0));
 }
 
+void gen_id_eno(struct treenode *bnode)
+{
+       printf("\t//gen_id_eno\n");
+       KIDKIDREG2PARM(1,0);
+       printf("\taddq %%%s, %%%s\n", KIDKID_REG(1,0), KIDKID_REG(1,1));
+       printf("\tsubq %%%s, %%%s\n", KIDKID_REG(1,1), BN_REG);
+}
+
 void gen_e_field(struct treenode *bnode, char *instr)
 {
        printf("\t//gen_e_field(%s)\n", instr);
@@ -193,6 +201,8 @@ expr: O_SUB(expr,imm)           # 1 # gen_e_imm(bnode, "subq");
 expr: O_SUB(expr,O_SUB(O_ID,expr)) # 2 # gen_subspecial(bnode, 0);
 expr: O_SUB(expr,O_SUB(imm,expr))  # 2 # gen_subspecial(bnode, 1);
 
+expr: O_SUB(expr, O_ADD(O_ID,expr))    # 1 # gen_id_eno(bnode);
+
 expr: O_SUB(expr,O_MUL(O_MONE,expr))   # 1 # gen_lea(bnode,0);
 expr: O_SUB(expr,O_MUL(O_MTWO,expr))   # 1 # gen_lea(bnode,0);
 expr: O_SUB(expr,O_MUL(O_MFOUR,expr))  # 1 # gen_lea(bnode,0);