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Add more peephole optimisations

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This commit is contained in:
Steven Flintham 2017-07-28 23:03:44 +01:00
parent 7ad91aa9e3
commit e9c4e062c3
1 changed files with 73 additions and 0 deletions
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73
src/toolsrc/codegen.c
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@ -995,6 +995,17 @@ int crunch_seq(t_opseq **seq)
freeops = 1;
}
break;
case NE_CODE:
if (!op->val)
freeops = -2; // Remove ZERO:ISNE
break;
case EQ_CODE:
if (!op->val)
{
op->code = LOGIC_NOT_CODE;
freeops = 1;
}
break;
case CONST_CODE: // Collapse constant operation
if ((opnextnext = opnext->nextop))
switch (opnextnext->code)
@ -1173,6 +1184,38 @@ int crunch_seq(t_opseq **seq)
break;
}
break; // GADDR_CODE
case LLW_CODE:
// LLW [n]:CB 8:SHR -> LLB [n+1]
if ((opnext->code == CONST_CODE) && (opnext->val == 8))
{
if ((opnextnext = opnext->nextop))
{
if (opnextnext->code == SHR_CODE)
{
op->code = LLB_CODE;
op->offsz++;
freeops = 2;
break;
}
}
}
break; // LLW_CODE
case LAW_CODE:
// LAW x:CB 8:SHR -> LAB x+1
if ((opnext->code == CONST_CODE) && (opnext->val == 8))
{
if ((opnextnext = opnext->nextop))
{
if (opnextnext->code == SHR_CODE)
{
op->code = LAB_CODE;
op->offsz++;
freeops = 2;
break;
}
}
}
break; // LAW_CODE
case LOGIC_NOT_CODE:
switch (opnext->code)
{
@ -1188,6 +1231,36 @@ int crunch_seq(t_opseq **seq)
break;
}
break; // LOGIC_NOT_CODE
case SLB_CODE:
if ((opnext->code == LLB_CODE) && (op->offsz == opnext->offsz))
{
op->code = DLB_CODE;
freeops = 1;
}
break; // SLB_CODE
case SLW_CODE:
if ((opnext->code == LLW_CODE) && (op->offsz == opnext->offsz))
{
op->code = DLW_CODE;
freeops = 1;
}
break; // SLW_CODE
case SAB_CODE:
if ((opnext->code == LAB_CODE) && (op->tag == opnext->tag) &&
(op->offsz == opnext->offsz) && (op->type == opnext->type))
{
op->code = DAB_CODE;
freeops = 1;
}
break; // SAB_CODE
case SAW_CODE:
if ((opnext->code == LAW_CODE) && (op->tag == opnext->tag) &&
(op->offsz == opnext->offsz) && (op->type == opnext->type))
{
op->code = DAW_CODE;
freeops = 1;
}
break; // SAW_CODE
}
//
// Free up crunched ops. If freeops is positive we free up that many ops