diff options
Diffstat (limited to 'src/runtime.js')
| -rw-r--r-- | src/runtime.js | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/src/runtime.js b/src/runtime.js index 8e5238da..39aed12c 100644 --- a/src/runtime.js +++ b/src/runtime.js @@ -118,6 +118,41 @@ var Runtime = { INT_TYPES: set('i1', 'i8', 'i16', 'i32', 'i64'), FLOAT_TYPES: set('float', 'double'), + // Mirrors processMathop's treatment of constants (which we optimize directly) + bitshift64: function(value, op, bits) { + var ander = Math.pow(2, bits)-1; + if (bits < 32) { + switch (op) { + case 'shl': + return [value[0] << bits, (value[1] << bits) | ((value[0]&(ander << (32 - bits))) >>> (32 - bits))]; + case 'ashr': + return [(((value[0] >>> bits ) | ((value[1]&ander) << (32 - bits))) >> 0) >>> 0, (value[1] >> bits) >>> 0]; + case 'lshr': + return [((value[0] >>> bits) | ((value[1]&ander) << (32 - bits))) >>> 0, value[1] >>> bits]; + } + } else if (bits == 32) { + switch (op) { + case 'shl': + return [0, value[0]]; + case 'ashr': + return [value[1], (value[1]|0) < 0 ? ander : 0]; + case 'lshr': + return [value[1], 0]; + } + } else { // bits > 32 + switch (op) { + case 'shl': + return [0, value[0] << (bits - 32)]; + case 'ashr': + return [(value[1] >> (bits - 32)) >>> 0, (value[1]|0) < 0 ? ander : 0]; + case 'lshr': + return [value[1] >>> (bits - 32) , 0]; + } + } + abort('unknown bitshift64 op: ' + [value, op, bits]); + }, + + // Imprecise bitops utilities or64: function(x, y) { var l = (x | 0) | (y | 0); var h = (Math.round(x / 4294967296) | Math.round(y / 4294967296)) * 4294967296; |