Add comparisons; tak example

1 files changed, 77 insertions, 41 deletions

diff --git a/sjit_c.c b/sjit_c.c
index caae10f..21a4b70 100644
--- a/sjit_c.c
+++ b/sjit_c.c
@@ -12,18 +12,27 @@ enum instr {
 
 	Call,
 	Jmp,
-	JmpTrue,
+	JmpCond,
 	Ret,
 	Halt,
 
-	IAdd,
-	IMul,
-	ISub,
-	IDiv
+	Op
 };
 
-static inline uint32_t instr_size(enum instr instr) {
-	switch (instr) {
+enum op {
+	OAdd, OMul,
+	OSub, ODiv
+};
+
+enum cond {
+	CEq, CNe,
+	CLt, CLe,
+	CGt, CGe,
+	CTrue
+};
+
+static inline uint32_t instr_size(uint64_t *pgm) {
+	switch (*pgm) {
 		case PushRef: return 5+1;
 		case PushI:   return 7+1;
 		case Put:     return 1+5;
@@ -31,17 +40,25 @@ static inline uint32_t instr_size(enum instr instr) {
 
 		case Call:    return 5;
 		case Jmp:     return 5;
-		case JmpTrue: return 1+3+6;
+		case JmpCond: switch (pgm[1]) {
+			case CTrue: return 1+3+6;
+			default:    return 1+1+3+6;
+		}
 		case Ret:     return 1;
 		case Halt:    return 1+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;
+		case Op: switch (pgm[1]) {
+			case OAdd:
+			case OSub: return 1+4+3+4;
+			case OMul: return 1+4+4+4;
+			case ODiv: return 1+4+3+3+4;
+			default:
+				fprintf(stderr,"unknown operator %d\n",(int)pgm[1]);
+				exit(1);
+		}
 
 		default:
-			fprintf(stderr,"unknown instruction %d\n",instr);
+			fprintf(stderr,"unknown instruction %d\n",(int)*pgm);
 			exit(1);
 	}
 }
@@ -127,21 +144,41 @@ static inline void gen_instr(char *full_code, char **code_p, uint64_t **pgm_p, u
 			pgm+=2;
 			code+=5;
 			break;
-		case JmpTrue:
-			arg=pgm[1];
+		case JmpCond:
+		{
+			enum cond cond=pgm[1];
+			arg=pgm[2];
 #ifdef DEBUG_JIT_INSTRUCTIONS
-			fprintf(stderr,"JmpTrue %lu -> %d\n",arg,mapping[arg]-(uint32_t)(&code[10]-full_code));
+			fprintf(stderr,"JmpCond %d %lu -> %d\n",(int)cond,arg,mapping[arg]-(uint32_t)(&code[10]-full_code));
 #endif
 			code[0]='\x59'; /* pop rcx */
-			code[1]='\x48'; /* test rcx,rcx */
-			code[2]='\x85';
-			code[3]='\xc9';
-			code[4]='\x0f'; /* jne ARG */
-			code[5]='\x85';
-			*(uint32_t*)&code[6]=mapping[arg]-(&code[10]-full_code);
-			pgm+=2;
-			code+=10;
+			if (cond==CTrue) {
+				code[1]='\x48'; /* test rcx,rcx */
+				code[2]='\x85';
+				code[3]='\xc9';
+				code+=4;
+			} else {
+				code[1]='\x58'; /* pop rax */
+				code[2]='\x48'; /* cmp rax,rcx */
+				code[3]='\x3b';
+				code[4]='\xc1';
+				code+=5;
+			}
+			code[0]='\x0f'; /* jcc */
+			switch (cond) {
+				case CEq: code[1]='\x84'; break;
+				case CTrue:
+				case CNe: code[1]='\x85'; break;
+				case CLt: code[1]='\x8c'; break;
+				case CLe: code[1]='\x8e'; break;
+				case CGt: code[1]='\x8f'; break;
+				case CGe: code[1]='\x8d'; break;
+			}
+			*(uint32_t*)&code[2]=mapping[arg]-(&code[6]-full_code);
+			pgm+=3;
+			code+=6;
 			break;
+		}
 		case Ret:
 #ifdef DEBUG_JIT_INSTRUCTIONS
 			fprintf(stderr,"Ret\n");
@@ -160,32 +197,30 @@ static inline void gen_instr(char *full_code, char **code_p, uint64_t **pgm_p, u
 			code+=2;
 			break;
 
-		case IAdd:
-		case IMul:
-		case ISub:
-		case IDiv:
+		case Op:
+			arg=pgm[1];
 #ifdef DEBUG_JIT_INSTRUCTIONS
-			fprintf(stderr,"I<Op>\n");
+			fprintf(stderr,"Op %d\n",(int)arg);
 #endif
 			/* pop rax */
 			code[0]='\x58';
 			/* mov rcx,[rsp] */
 			code[1]='\x48'; code[2]='\x8b'; code[3]='\x0c'; code[4]='\x24';
-			switch (*pgm) {
-				case IAdd:
-				case ISub:
+			switch (arg) {
+				case OAdd:
+				case OSub:
 					/* {add,sub} rax,rcx */
 					code[5]='\x48';
-					code[6]=*pgm==IAdd ? '\x01' : '\x29';
+					code[6]=arg==OAdd ? '\x01' : '\x29';
 					code[7]='\xc8';
 					code+=8;
 					break;
-				case IMul:
+				case OMul:
 					/* imul rax,rcx */
 					code[5]='\x48'; code[6]='\x0f'; code[7]='\xaf'; code[8]='\xc1';
 					code+=9;
 					break;
-				case IDiv:
+				case ODiv:
 					/* xor rdx,rdx */
 					code[5]='\x48'; code[6]='\x31'; code[7]='\xd2';
 					/* idiv rcx */
@@ -195,7 +230,7 @@ static inline void gen_instr(char *full_code, char **code_p, uint64_t **pgm_p, u
 			}
 			/* mov [rsp],rax */
 			code[0]='\x48'; code[1]='\x89'; code[2]='\x04'; code[3]='\x24';
-			pgm++;
+			pgm+=2;
 			code+=4;
 			break;
 
@@ -222,19 +257,20 @@ char *jit_append(char *code_block, uint32_t code_len, char *code_ptr,
 
 	uint64_t *pgm_p=pgm;
 	for (i=n_instr; i<n_instr+len; i++) {
-		enum instr instr=(enum instr)*pgm_p;
-
 		mapping[i]=code_i;
-		code_i+=instr_size(instr);
+		code_i+=instr_size(pgm_p);
 
-		switch (instr) {
+		switch (*pgm_p) {
+			case JmpCond:
+				pgm_p+=3;
+				break;
 			case PushRef:
 			case PushI:
 			case Put:
 			case Pop:
 			case Call:
 			case Jmp:
-			case JmpTrue:
+			case Op:
 				pgm_p+=2;
 				break;
 			default: