Inline +, *, - and /

1 files changed, 33 insertions, 35 deletions

diff --git a/sjit_c.c b/sjit_c.c
index 325de47..caae10f 100644
--- a/sjit_c.c
+++ b/sjit_c.c
@@ -16,10 +16,10 @@ enum instr {
 	Ret,
 	Halt,
 
-	IAddRet,
-	IMulRet,
-	ISubRet,
-	IDivRet
+	IAdd,
+	IMul,
+	ISub,
+	IDiv
 };
 
 static inline uint32_t instr_size(enum instr instr) {
@@ -35,10 +35,10 @@ static inline uint32_t instr_size(enum instr instr) {
 		case Ret:     return 1;
 		case Halt:    return 1+1;
 
-		case IAddRet:
-		case ISubRet: return 5+5+3+5+1;
-		case IMulRet: return 5+5+4+5+1;
-		case IDivRet: return 5+5+3+3+5+1;
+		case IAdd:
+		case ISub:    return 1+4+3+4;
+		case IMul:    return 1+4+4+4;
+		case IDiv:    return 1+4+3+3+4;
 
 		default:
 			fprintf(stderr,"unknown instruction %d\n",instr);
@@ -160,45 +160,43 @@ static inline void gen_instr(char *full_code, char **code_p, uint64_t **pgm_p, u
 			code+=2;
 			break;
 
-		case IAddRet:
-		case IMulRet:
-		case ISubRet:
-		case IDivRet:
+		case IAdd:
+		case IMul:
+		case ISub:
+		case IDiv:
 #ifdef DEBUG_JIT_INSTRUCTIONS
-			fprintf(stderr,"I<Op>Ret\n");
+			fprintf(stderr,"I<Op>\n");
 #endif
-			/* mov rax,[rsp+8] */
-			code[0]='\x48'; code[1]='\x8b'; code[2]='\x44'; code[3]='\x24'; code[4]='\x08';
-			/* mov rcx,[rsp+16] */
-			code[5]='\x48'; code[6]='\x8b'; code[7]='\x4c'; code[8]='\x24'; code[9]='\x10';
+			/* pop rax */
+			code[0]='\x58';
+			/* mov rcx,[rsp] */
+			code[1]='\x48'; code[2]='\x8b'; code[3]='\x0c'; code[4]='\x24';
 			switch (*pgm) {
-				case IAddRet:
-				case ISubRet:
+				case IAdd:
+				case ISub:
 					/* {add,sub} rax,rcx */
-					code[10]='\x48';
-					code[11]=*pgm==IAddRet ? '\x01' : '\x29';
-					code[12]='\xc8';
-					code+=13;
+					code[5]='\x48';
+					code[6]=*pgm==IAdd ? '\x01' : '\x29';
+					code[7]='\xc8';
+					code+=8;
 					break;
-				case IMulRet:
+				case IMul:
 					/* imul rax,rcx */
-					code[10]='\x48'; code[11]='\x0f'; code[12]='\xaf'; code[13]='\xc1';
-					code+=14;
+					code[5]='\x48'; code[6]='\x0f'; code[7]='\xaf'; code[8]='\xc1';
+					code+=9;
 					break;
-				case IDivRet:
+				case IDiv:
 					/* xor rdx,rdx */
-					code[10]='\x48'; code[11]='\x31'; code[12]='\xd2';
+					code[5]='\x48'; code[6]='\x31'; code[7]='\xd2';
 					/* idiv rcx */
-					code[13]='\x48'; code[14]='\xf7'; code[15]='\xf9';
-					code+=16;
+					code[8]='\x48'; code[9]='\xf7'; code[10]='\xf9';
+					code+=11;
 					break;
 			}
-			/* mov [rsp+16],rax */
-			code[0]='\x48'; code[1]='\x89'; code[2]='\x44'; code[3]='\x24'; code[4]='\x10';
-			/* retq */
-			code[5]='\xc3';
+			/* mov [rsp],rax */
+			code[0]='\x48'; code[1]='\x89'; code[2]='\x04'; code[3]='\x24';
 			pgm++;
-			code+=6;
+			code+=4;
 			break;
 
 		default: