expression simplification was sometimes leaving data on the stack.

This commit is contained in:
Kelvin Sherlock 2017-01-16 16:14:56 -05:00
parent 5db92377d6
commit 6b99d138a2
1 changed files with 17 additions and 2 deletions

View File

@ -2,6 +2,9 @@
#include <vector>
#include "obj816.h"
#include <sysexits.h>
#include <err.h>
/* a ** b */
uint32_t power(uint32_t a, uint32_t b) {
@ -21,6 +24,8 @@ bool unary_op(unsigned op, std::vector<expr> &v) {
case OP_NOT: a.value = !a.value; break;
case OP_NEG: a.value = -a.value; break;
case OP_FLP: a.value = ~a.value; break;
default:
errx(EX_SOFTWARE, "Unsupported unary op %02x", a.tag);
}
return true;
}
@ -54,6 +59,8 @@ bool binary_op(unsigned op, std::vector<expr> &v) {
case OP_LT: value = (int32_t)a.value < (int32_t)b.value; break;
case OP_UGT: value = a.value > b.value; break;
case OP_ULT: value = a.value < b.value; break;
default:
errx(EX_SOFTWARE, "Unsupported binary op %02x", a.tag);
}
v.pop_back();
v.back().value = value;
@ -86,8 +93,16 @@ bool binary_op(unsigned op, std::vector<expr> &v) {
// optimization... regardless of where it's located, shifting > 24 bits will result in 0...
if (a.tag == OP_LOC && b.tag == OP_VAL) {
switch(op) {
case OP_ADD: a.value += b.value; return true;
case OP_SUB: a.value -= b.value; return true;
case OP_ADD: {
a.value += b.value;
v.pop_back();
return true;
}
case OP_SUB: {
a.value -= b.value;
v.pop_back();
return true;
}
}
}