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-rw-r--r--code/qcommon/vm_interpreted.c122
1 files changed, 57 insertions, 65 deletions
diff --git a/code/qcommon/vm_interpreted.c b/code/qcommon/vm_interpreted.c
index 6b303d8..d348ee6 100644
--- a/code/qcommon/vm_interpreted.c
+++ b/code/qcommon/vm_interpreted.c
@@ -169,7 +169,8 @@ VM_PrepareInterpreter
*/
void VM_PrepareInterpreter( vm_t *vm, vmHeader_t *header ) {
int op;
- int pc;
+ int byte_pc;
+ int int_pc;
byte *code;
int instruction;
int *codeBase;
@@ -179,22 +180,24 @@ void VM_PrepareInterpreter( vm_t *vm, vmHeader_t *header ) {
// we don't need to translate the instructions, but we still need
// to find each instructions starting point for jumps
- pc = 0;
+ int_pc = byte_pc = 0;
instruction = 0;
code = (byte *)header + header->codeOffset;
codeBase = (int *)vm->codeBase;
+ // Copy and expand instructions to words while building instruction table
while ( instruction < header->instructionCount ) {
- vm->instructionPointers[ instruction ] = pc;
+ vm->instructionPointers[ instruction ] = int_pc;
instruction++;
- op = code[ pc ];
- codeBase[pc] = op;
- if ( pc > header->codeLength ) {
+ op = (int)code[ byte_pc ];
+ codeBase[int_pc] = op;
+ if ( byte_pc > header->codeLength ) {
Com_Error( ERR_FATAL, "VM_PrepareInterpreter: pc > header->codeLength" );
}
- pc++;
+ byte_pc++;
+ int_pc++;
// these are the only opcodes that aren't a single byte
switch ( op ) {
@@ -219,32 +222,33 @@ void VM_PrepareInterpreter( vm_t *vm, vmHeader_t *header ) {
case OP_GTF:
case OP_GEF:
case OP_BLOCK_COPY:
- codeBase[pc+0] = loadWord(&code[pc]);
- pc += 4;
+ codeBase[int_pc] = loadWord(&code[byte_pc]);
+ byte_pc += 4;
+ int_pc++;
break;
case OP_ARG:
- codeBase[pc+0] = code[pc];
- pc += 1;
+ codeBase[int_pc] = (int)code[byte_pc];
+ byte_pc++;
+ int_pc++;
break;
default:
break;
}
}
- pc = 0;
+ int_pc = 0;
instruction = 0;
code = (byte *)header + header->codeOffset;
- codeBase = (int *)vm->codeBase;
-
+
+ // Now that the code has been expanded to int-sized opcodes, we'll translate instruction index
+ //into an index into codeBase[], which contains opcodes and operands.
while ( instruction < header->instructionCount ) {
- op = code[ pc ];
+ op = codeBase[ int_pc ];
instruction++;
- pc++;
+ int_pc++;
+
switch ( op ) {
- case OP_ENTER:
- case OP_CONST:
- case OP_LOCAL:
- case OP_LEAVE:
+ // These ops need to translate addresses in jumps from instruction index to int index
case OP_EQ:
case OP_NE:
case OP_LTI:
@@ -261,34 +265,22 @@ void VM_PrepareInterpreter( vm_t *vm, vmHeader_t *header ) {
case OP_LEF:
case OP_GTF:
case OP_GEF:
- case OP_BLOCK_COPY:
- switch(op) {
- case OP_EQ:
- case OP_NE:
- case OP_LTI:
- case OP_LEI:
- case OP_GTI:
- case OP_GEI:
- case OP_LTU:
- case OP_LEU:
- case OP_GTU:
- case OP_GEU:
- case OP_EQF:
- case OP_NEF:
- case OP_LTF:
- case OP_LEF:
- case OP_GTF:
- case OP_GEF:
- codeBase[pc] = vm->instructionPointers[codeBase[pc]];
- break;
- default:
- break;
- }
- pc += 4;
+ // codeBase[pc] is the instruction index. Convert that into an offset into
+ //the int-aligned codeBase[] by the lookup table.
+ codeBase[int_pc] = vm->instructionPointers[codeBase[int_pc]];
+ int_pc++;
break;
+
+ // These opcodes have an operand that isn't an instruction index
+ case OP_ENTER:
+ case OP_CONST:
+ case OP_LOCAL:
+ case OP_LEAVE:
+ case OP_BLOCK_COPY:
case OP_ARG:
- pc += 1;
+ int_pc++;
break;
+
default:
break;
}
@@ -432,14 +424,14 @@ nextInstruction2:
r1 = r0;
r0 = *opStack = r2;
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction2;
case OP_LOCAL:
opStack++;
r1 = r0;
r0 = *opStack = r2+programStack;
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction2;
case OP_LOAD4:
@@ -493,7 +485,7 @@ nextInstruction2:
dest = (int *)&image[ desti ];
memcpy(dest, src, count);
- programCounter += 4;
+ programCounter += 1;
opStack -= 2;
}
goto nextInstruction;
@@ -578,7 +570,7 @@ nextInstruction2:
// get size of stack frame
v1 = r2;
- programCounter += 4;
+ programCounter += 1;
programStack -= v1;
#ifdef DEBUG_VM
// save old stack frame for debugging traces
@@ -636,7 +628,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -646,7 +638,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -656,7 +648,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -666,7 +658,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -676,7 +668,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -686,7 +678,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -696,7 +688,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -706,7 +698,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -716,7 +708,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -726,7 +718,7 @@ nextInstruction2:
programCounter = r2; //vm->instructionPointers[r2];
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
goto nextInstruction;
}
@@ -736,7 +728,7 @@ nextInstruction2:
opStack -= 2;
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
opStack -= 2;
goto nextInstruction;
}
@@ -747,7 +739,7 @@ nextInstruction2:
opStack -= 2;
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
opStack -= 2;
goto nextInstruction;
}
@@ -758,7 +750,7 @@ nextInstruction2:
opStack -= 2;
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
opStack -= 2;
goto nextInstruction;
}
@@ -769,7 +761,7 @@ nextInstruction2:
opStack -= 2;
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
opStack -= 2;
goto nextInstruction;
}
@@ -780,7 +772,7 @@ nextInstruction2:
opStack -= 2;
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
opStack -= 2;
goto nextInstruction;
}
@@ -791,7 +783,7 @@ nextInstruction2:
opStack -= 2;
goto nextInstruction;
} else {
- programCounter += 4;
+ programCounter += 1;
opStack -= 2;
goto nextInstruction;
}
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 22:02:01 +0000