diff options
| -rw-r--r-- | src/compiler/nir/nir_opt_algebraic.py | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py index b5d90b22606..f181044faf2 100644 --- a/src/compiler/nir/nir_opt_algebraic.py +++ b/src/compiler/nir/nir_opt_algebraic.py @@ -381,11 +381,16 @@ optimizations = [ 'options->lower_unpack_snorm_4x8'), ] -def fexp2i(exp): - # We assume that exp is already in the range [-126, 127]. - return ('ishl', ('iadd', exp, 127), 23) - -def ldexp32(f, exp): +def fexp2i(exp, bits): + # We assume that exp is already in the right range. + if bits == 32: + return ('ishl', ('iadd', exp, 127), 23) + elif bits == 64: + return ('pack_double_2x32_split', 0, ('ishl', ('iadd', exp, 1023), 20)) + else: + assert False + +def ldexp(f, exp, bits): # First, we clamp exp to a reasonable range. The maximum possible range # for a normal exponent is [-126, 127] and, throwing in denormals, you get # a maximum range of [-149, 127]. This means that we can potentially have @@ -396,7 +401,12 @@ def ldexp32(f, exp): # handles a range on exp of [-252, 254] which allows you to create any # value (including denorms if the hardware supports it) and to adjust the # exponent of any normal value to anything you want. - exp = ('imin', ('imax', exp, -252), 254) + if bits == 32: + exp = ('imin', ('imax', exp, -252), 254) + elif bits == 64: + exp = ('imin', ('imax', exp, -2044), 2046) + else: + assert False # Now we compute two powers of 2, one for exp/2 and one for exp-exp/2. # (We use ishr which isn't the same for -1, but the -1 case still works @@ -406,11 +416,14 @@ def ldexp32(f, exp): # that you can get with normalized values. Instead, we create two powers # of two and multiply by them each in turn. That way the effective range # of our exponent is doubled. - pow2_1 = fexp2i(('ishr', exp, 1)) - pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1))) + pow2_1 = fexp2i(('ishr', exp, 1), bits) + pow2_2 = fexp2i(('isub', exp, ('ishr', exp, 1)), bits) return ('fmul', ('fmul', f, pow2_1), pow2_2) -optimizations += [(('ldexp@32', 'x', 'exp'), ldexp32('x', 'exp'))] +optimizations += [ + (('ldexp@32', 'x', 'exp'), ldexp('x', 'exp', 32)), + (('ldexp@64', 'x', 'exp'), ldexp('x', 'exp', 64)), +] # Unreal Engine 4 demo applications open-codes bitfieldReverse() def bitfield_reverse(u): |