diff options
Diffstat (limited to 'cpu_dsl.py')
| -rwxr-xr-x | cpu_dsl.py | 34 |
1 files changed, 26 insertions, 8 deletions
@@ -242,7 +242,7 @@ class Op: decl = '' if needsCarry or needsOflow or needsHalf: size = prog.paramSize(rawParams[2]) - if needsCarry: + if needsCarry and op != 'lsr': size *= 2 decl,name = prog.getTemp(size) dst = prog.carryFlowDst = name @@ -325,9 +325,13 @@ def _updateFlagsCImpl(prog, params, rawParams): if calc == 'sign': resultBit = prog.paramSize(prog.lastDst) - 1 elif calc == 'carry': - resultBit = prog.paramSize(prog.lastDst) - if prog.lastOp.op == 'ror': - resultBit -= 1 + if prog.lastOp.op in ('asr', 'lsr'): + resultBit = 0 + myRes = prog.lastA + else: + resultBit = prog.paramSize(prog.lastDst) + if prog.lastOp.op == 'ror': + resultBit -= 1 elif calc == 'half': resultBit = prog.paramSize(prog.lastDst) - 4 myRes = '({a} ^ {b} ^ {res})'.format(a = prog.lastA, b = prog.lastB, res = lastDst) @@ -453,10 +457,24 @@ def _cmpCImpl(prog, params, rawParams, flagUpdates): prog.lastDst = rawParams[1] return '\n\t{var} = {b} - {a};'.format(var = tmpvar, a = params[0], b = params[1]) -def _asrCImpl(prog, params, rawParams): - shiftSize = prog.paramSize(rawParams[0]) - mask = 1 << (shiftSize - 1) - return '\n\t{dst} = ({a} >> {b}) | ({a} & {mask});'.format(a = params[0], b = params[1], dst = params[2], mask = mask) +def _asrCImpl(prog, params, rawParams, flagUpdates): + needsCarry = False + if flagUpdates: + for flag in flagUpdates: + calc = prog.flags.flagCalc[flag] + if calc == 'carry': + needsCarry = True + decl = '' + size = prog.paramSize(rawParams[2]) + if needsCarry: + decl,name = prog.getTemp(size * 2) + dst = prog.carryFlowDst = name + prog.lastA = params[0] + else: + dst = params[2] + mask = 1 << (size - 1) + return decl + '\n\t{dst} = ({a} >> {b}) | ({a} & {mask} ? 0xFFFFFFFFU << ({size} - {b}) : 0);'.format( + a = params[0], b = params[1], dst = dst, mask = mask, size=size) def _sext(size, src): if size == 16: |