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Avoid optimizations around jsr and pla

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This commit is contained in:
Jason Turner
2021-05-19 22:34:21 -06:00
parent 61e3609f47
commit 8894f4b1cf
2 changed files with 20 additions and 6 deletions
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9
include/optimizer.hpp
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@ -64,6 +64,10 @@ bool optimize(std::vector<mos6502> &instructions, const Personality &personality
// someone just loaded lda with a different value, so we need to abort!
break;
}
// abort at pla
if (instructions[next_op].opcode == mos6502::OpCode::pla) { break; }
// abort at jsr
if (instructions[next_op].opcode == mos6502::OpCode::jsr) { break; }
// abort at label
if (instructions[next_op].type == ASMLine::Type::Label) { break; }
@ -141,7 +145,8 @@ bool optimize(std::vector<mos6502> &instructions, const Personality &personality
if (instructions[op].opcode == mos6502::OpCode::ldy && instructions[op].op.type == Operand::Type::literal) {
auto op2 = op + 1;
while (op2 < instructions.size() && (instructions[op2].type != ASMLine::Type::Label)) {
while (op2 < instructions.size() && (instructions[op2].type != ASMLine::Type::Label)
&& (instructions[op2].opcode == mos6502::OpCode::jsr)) {
// while inside this label
if (instructions[op2].opcode == mos6502::OpCode::ldy) {
@ -163,7 +168,7 @@ bool optimize(std::vector<mos6502> &instructions, const Personality &personality
for (size_t op = 0; op < instructions.size() - 1; ++op) {
if (instructions[op].opcode == mos6502::OpCode::lda && instructions[op].op.type == Operand::Type::literal) {
const auto operand = instructions[op].op;
auto op2 = op + 1;
auto op2 = op + 1;
// look for multiple stores of the same value
while (
op2 < instructions.size()