# Written in the form (<search>, <replace>) where <search> is an expression
# and <replace> is either an expression or a value. An expression is
-# defined as a tuple of the form (<op>, <src0>, <src1>, <src2>, <src3>)
+# defined as a tuple of the form ([~]<op>, <src0>, <src1>, <src2>, <src3>)
# where each source is either an expression or a value. A value can be
# either a numeric constant or a string representing a variable name.
#
+# If the opcode in a search expression is prefixed by a '~' character, this
+# indicates that the operation is inexact. Such operations will only get
+# applied to SSA values that do not have the exact bit set. This should be
+# used by by any optimizations that are not bit-for-bit exact. It should not,
+# however, be used for backend-requested lowering operations as those need to
+# happen regardless of precision.
+#
# Variable names are specified as "[#]name[@type]" where "#" inicates that
# the given variable will only match constants and the type indicates that
# the given variable will only match values from ALU instructions with the
(('fabs', ('fneg', a)), ('fabs', a)),
(('iabs', ('iabs', a)), ('iabs', a)),
(('iabs', ('ineg', a)), ('iabs', a)),
- (('fadd', a, 0.0), a),
+ (('~fadd', a, 0.0), a),
(('iadd', a, 0), a),
(('usadd_4x8', a, 0), a),
(('usadd_4x8', a, ~0), ~0),
- (('fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
+ (('~fadd', ('fmul', a, b), ('fmul', a, c)), ('fmul', a, ('fadd', b, c))),
(('iadd', ('imul', a, b), ('imul', a, c)), ('imul', a, ('iadd', b, c))),
- (('fadd', ('fneg', a), a), 0.0),
+ (('~fadd', ('fneg', a), a), 0.0),
(('iadd', ('ineg', a), a), 0),
(('iadd', ('ineg', a), ('iadd', a, b)), b),
(('iadd', a, ('iadd', ('ineg', a), b)), b),
- (('fadd', ('fneg', a), ('fadd', a, b)), b),
- (('fadd', a, ('fadd', ('fneg', a), b)), b),
- (('fmul', a, 0.0), 0.0),
+ (('~fadd', ('fneg', a), ('fadd', a, b)), b),
+ (('~fadd', a, ('fadd', ('fneg', a), b)), b),
+ (('~fmul', a, 0.0), 0.0),
(('imul', a, 0), 0),
(('umul_unorm_4x8', a, 0), 0),
(('umul_unorm_4x8', a, ~0), a),
(('imul', a, 1), a),
(('fmul', a, -1.0), ('fneg', a)),
(('imul', a, -1), ('ineg', a)),
- (('ffma', 0.0, a, b), b),
- (('ffma', a, 0.0, b), b),
- (('ffma', a, b, 0.0), ('fmul', a, b)),
+ (('~ffma', 0.0, a, b), b),
+ (('~ffma', a, 0.0, b), b),
+ (('~ffma', a, b, 0.0), ('fmul', a, b)),
(('ffma', a, 1.0, b), ('fadd', a, b)),
(('ffma', 1.0, a, b), ('fadd', a, b)),
- (('flrp', a, b, 0.0), a),
- (('flrp', a, b, 1.0), b),
- (('flrp', a, a, b), a),
- (('flrp', 0.0, a, b), ('fmul', a, b)),
+ (('~flrp', a, b, 0.0), a),
+ (('~flrp', a, b, 1.0), b),
+ (('~flrp', a, a, b), a),
+ (('~flrp', 0.0, a, b), ('fmul', a, b)),
+ (('~flrp', a, b, ('b2f', c)), ('bcsel', c, b, a), 'options->lower_flrp'),
(('flrp', a, b, c), ('fadd', ('fmul', c, ('fsub', b, a)), a), 'options->lower_flrp'),
(('ffract', a), ('fsub', a, ('ffloor', a)), 'options->lower_ffract'),
- (('fadd', ('fmul', a, ('fadd', 1.0, ('fneg', c))), ('fmul', b, c)), ('flrp', a, b, c), '!options->lower_flrp'),
- (('fadd', a, ('fmul', c, ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp'),
+ (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', ('b2f', c)))), ('fmul', b, ('b2f', c))), ('bcsel', c, b, a), 'options->lower_flrp'),
+ (('~fadd', ('fmul', a, ('fadd', 1.0, ('fneg', c ))), ('fmul', b, c )), ('flrp', a, b, c), '!options->lower_flrp'),
+ (('~fadd', a, ('fmul', ('b2f', c), ('fadd', b, ('fneg', a)))), ('bcsel', c, b, a), 'options->lower_flrp'),
+ (('~fadd', a, ('fmul', c , ('fadd', b, ('fneg', a)))), ('flrp', a, b, c), '!options->lower_flrp'),
(('ffma', a, b, c), ('fadd', ('fmul', a, b), c), 'options->lower_ffma'),
- (('fadd', ('fmul', a, b), c), ('ffma', a, b, c), '!options->lower_ffma'),
+ (('~fadd', ('fmul', a, b), c), ('ffma', a, b, c), '!options->lower_ffma'),
# Comparison simplifications
- (('inot', ('flt', a, b)), ('fge', a, b)),
- (('inot', ('fge', a, b)), ('flt', a, b)),
- (('inot', ('feq', a, b)), ('fne', a, b)),
- (('inot', ('fne', a, b)), ('feq', a, b)),
+ (('~inot', ('flt', a, b)), ('fge', a, b)),
+ (('~inot', ('fge', a, b)), ('flt', a, b)),
+ (('~inot', ('feq', a, b)), ('fne', a, b)),
+ (('~inot', ('fne', a, b)), ('feq', a, b)),
(('inot', ('ilt', a, b)), ('ige', a, b)),
(('inot', ('ige', a, b)), ('ilt', a, b)),
(('inot', ('ieq', a, b)), ('ine', a, b)),
(('inot', ('ine', a, b)), ('ieq', a, b)),
+
+ # 0.0 >= b2f(a)
+ # b2f(a) <= 0.0
+ # b2f(a) == 0.0 because b2f(a) can only be 0 or 1
+ # inot(a)
+ (('fge', 0.0, ('b2f', a)), ('inot', a)),
+
+ # 0.0 < fabs(a)
+ # fabs(a) > 0.0
+ # fabs(a) != 0.0 because fabs(a) must be >= 0
+ # a != 0.0
+ (('flt', 0.0, ('fabs', a)), ('fne', a, 0.0)),
+
(('fge', ('fneg', ('fabs', a)), 0.0), ('feq', a, 0.0)),
- (('bcsel', ('flt', a, b), a, b), ('fmin', a, b)),
+ (('bcsel', ('flt', b, a), b, a), ('fmin', a, b)),
(('bcsel', ('flt', a, b), b, a), ('fmax', a, b)),
(('bcsel', ('inot', 'a@bool'), b, c), ('bcsel', a, c, b)),
(('bcsel', a, ('bcsel', a, b, c), d), ('bcsel', a, b, d)),
+ (('bcsel', a, True, 'b@bool'), ('ior', a, b)),
(('fmin', a, a), a),
(('fmax', a, a), a),
(('imin', a, a), a),
(('imax', a, a), a),
(('umin', a, a), a),
(('umax', a, a), a),
- (('fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
- (('fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
+ (('~fmin', ('fmax', a, 0.0), 1.0), ('fsat', a), '!options->lower_fsat'),
+ (('~fmax', ('fmin', a, 1.0), 0.0), ('fsat', a), '!options->lower_fsat'),
(('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
(('fsat', ('fsat', a)), ('fsat', a)),
- (('fmin', ('fmax', ('fmin', ('fmax', a, 0.0), 1.0), 0.0), 1.0), ('fmin', ('fmax', a, 0.0), 1.0)),
- (('ior', ('flt', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
- (('ior', ('flt', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
- (('ior', ('fge', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
- (('ior', ('fge', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
+ (('fmin', ('fmax', ('fmin', ('fmax', a, b), c), b), c), ('fmin', ('fmax', a, b), c)),
+ (('imin', ('imax', ('imin', ('imax', a, b), c), b), c), ('imin', ('imax', a, b), c)),
+ (('umin', ('umax', ('umin', ('umax', a, b), c), b), c), ('umin', ('umax', a, b), c)),
+ (('extract_u8', ('imin', ('imax', a, 0), 0xff), 0), ('imin', ('imax', a, 0), 0xff)),
+ (('~ior', ('flt', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
+ (('~ior', ('flt', a, c), ('flt', b, c)), ('flt', ('fmin', a, b), c)),
+ (('~ior', ('fge', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
+ (('~ior', ('fge', a, c), ('fge', b, c)), ('fge', ('fmax', a, b), c)),
+ (('fabs', ('slt', a, b)), ('slt', a, b)),
+ (('fabs', ('sge', a, b)), ('sge', a, b)),
+ (('fabs', ('seq', a, b)), ('seq', a, b)),
+ (('fabs', ('sne', a, b)), ('sne', a, b)),
(('slt', a, b), ('b2f', ('flt', a, b)), 'options->lower_scmp'),
(('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'),
(('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'),
(('ior', a, 0), a),
(('fxor', a, a), 0.0),
(('ixor', a, a), 0),
- (('fxor', a, 0.0), a),
(('ixor', a, 0), a),
(('inot', ('inot', a)), a),
# DeMorgan's Laws
(('ishr', a, 0), a),
(('ushr', 0, a), 0),
(('ushr', a, 0), a),
+ (('iand', 0xff, ('ushr', a, 24)), ('ushr', a, 24)),
+ (('iand', 0xffff, ('ushr', a, 16)), ('ushr', a, 16)),
# Exponential/logarithmic identities
- (('fexp2', ('flog2', a)), a), # 2^lg2(a) = a
- (('flog2', ('fexp2', a)), a), # lg2(2^a) = a
+ (('~fexp2', ('flog2', a)), a), # 2^lg2(a) = a
+ (('~flog2', ('fexp2', a)), a), # lg2(2^a) = a
(('fpow', a, b), ('fexp2', ('fmul', ('flog2', a), b)), 'options->lower_fpow'), # a^b = 2^(lg2(a)*b)
- (('fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
- (('fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
- ('fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
- (('fpow', a, 1.0), a),
- (('fpow', a, 2.0), ('fmul', a, a)),
- (('fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
- (('fpow', 2.0, a), ('fexp2', a)),
- (('fpow', ('fpow', a, 2.2), 0.454545), a),
- (('fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
- (('fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
- (('frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
- (('frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
- (('flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
- (('flog2', ('frcp', a)), ('fneg', ('flog2', a))),
- (('flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
- (('flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
- (('fadd', ('flog2', a), ('flog2', b)), ('flog2', ('fmul', a, b))),
- (('fadd', ('flog2', a), ('fneg', ('flog2', b))), ('flog2', ('fdiv', a, b))),
- (('fmul', ('fexp2', a), ('fexp2', b)), ('fexp2', ('fadd', a, b))),
+ (('~fexp2', ('fmul', ('flog2', a), b)), ('fpow', a, b), '!options->lower_fpow'), # 2^(lg2(a)*b) = a^b
+ (('~fexp2', ('fadd', ('fmul', ('flog2', a), b), ('fmul', ('flog2', c), d))),
+ ('~fmul', ('fpow', a, b), ('fpow', c, d)), '!options->lower_fpow'), # 2^(lg2(a) * b + lg2(c) + d) = a^b * c^d
+ (('~fpow', a, 1.0), a),
+ (('~fpow', a, 2.0), ('fmul', a, a)),
+ (('~fpow', a, 4.0), ('fmul', ('fmul', a, a), ('fmul', a, a))),
+ (('~fpow', 2.0, a), ('fexp2', a)),
+ (('~fpow', ('fpow', a, 2.2), 0.454545), a),
+ (('~fpow', ('fabs', ('fpow', a, 2.2)), 0.454545), ('fabs', a)),
+ (('~fsqrt', ('fexp2', a)), ('fexp2', ('fmul', 0.5, a))),
+ (('~frcp', ('fexp2', a)), ('fexp2', ('fneg', a))),
+ (('~frsq', ('fexp2', a)), ('fexp2', ('fmul', -0.5, a))),
+ (('~flog2', ('fsqrt', a)), ('fmul', 0.5, ('flog2', a))),
+ (('~flog2', ('frcp', a)), ('fneg', ('flog2', a))),
+ (('~flog2', ('frsq', a)), ('fmul', -0.5, ('flog2', a))),
+ (('~flog2', ('fpow', a, b)), ('fmul', b, ('flog2', a))),
+ (('~fadd', ('flog2', a), ('flog2', b)), ('flog2', ('fmul', a, b))),
+ (('~fadd', ('flog2', a), ('fneg', ('flog2', b))), ('flog2', ('fdiv', a, b))),
+ (('~fmul', ('fexp2', a), ('fexp2', b)), ('fexp2', ('fadd', a, b))),
# Division and reciprocal
- (('fdiv', 1.0, a), ('frcp', a)),
+ (('~fdiv', 1.0, a), ('frcp', a)),
(('fdiv', a, b), ('fmul', a, ('frcp', b)), 'options->lower_fdiv'),
- (('frcp', ('frcp', a)), a),
- (('frcp', ('fsqrt', a)), ('frsq', a)),
+ (('~frcp', ('frcp', a)), a),
+ (('~frcp', ('fsqrt', a)), ('frsq', a)),
(('fsqrt', a), ('frcp', ('frsq', a)), 'options->lower_fsqrt'),
- (('frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
+ (('~frcp', ('frsq', a)), ('fsqrt', a), '!options->lower_fsqrt'),
# Boolean simplifications
(('ieq', 'a@bool', True), a),
(('ine', 'a@bool', True), ('inot', a)),
(('i2b', ('b2i', a)), a),
(('f2i', ('ftrunc', a)), ('f2i', a)),
(('f2u', ('ftrunc', a)), ('f2u', a)),
+ (('i2b', ('ineg', a)), ('i2b', a)),
+ (('i2b', ('iabs', a)), ('i2b', a)),
+ (('fabs', ('b2f', a)), ('b2f', a)),
+ (('iabs', ('b2i', a)), ('b2i', a)),
+
+ # Byte extraction
+ (('ushr', a, 24), ('extract_u8', a, 3), '!options->lower_extract_byte'),
+ (('iand', 0xff, ('ushr', a, 16)), ('extract_u8', a, 2), '!options->lower_extract_byte'),
+ (('iand', 0xff, ('ushr', a, 8)), ('extract_u8', a, 1), '!options->lower_extract_byte'),
+ (('iand', 0xff, a), ('extract_u8', a, 0), '!options->lower_extract_byte'),
+
+ # Word extraction
+ (('ushr', a, 16), ('extract_u16', a, 1), '!options->lower_extract_word'),
+ (('iand', 0xffff, a), ('extract_u16', a, 0), '!options->lower_extract_word'),
# Subtracts
- (('fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
+ (('~fsub', a, ('fsub', 0.0, b)), ('fadd', a, b)),
(('isub', a, ('isub', 0, b)), ('iadd', a, b)),
(('ussub_4x8', a, 0), a),
(('ussub_4x8', a, ~0), 0),
(('isub', a, b), ('iadd', a, ('ineg', b)), 'options->lower_sub'),
(('fneg', a), ('fsub', 0.0, a), 'options->lower_negate'),
(('ineg', a), ('isub', 0, a), 'options->lower_negate'),
- (('fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
+ (('~fadd', a, ('fsub', 0.0, b)), ('fsub', a, b)),
(('iadd', a, ('isub', 0, b)), ('isub', a, b)),
(('fabs', ('fsub', 0.0, a)), ('fabs', a)),
(('iabs', ('isub', 0, a)), ('iabs', a)),
+ # Propagate negation up multiplication chains
+ (('fmul', ('fneg', a), b), ('fneg', ('fmul', a, b))),
+ (('imul', ('ineg', a), b), ('ineg', ('imul', a, b))),
+
+ # Reassociate constants in add/mul chains so they can be folded together.
+ # For now, we only handle cases where the constants are separated by
+ # a single non-constant. We could do better eventually.
+ (('~fmul', '#a', ('fmul', b, '#c')), ('fmul', ('fmul', a, c), b)),
+ (('imul', '#a', ('imul', b, '#c')), ('imul', ('imul', a, c), b)),
+ (('~fadd', '#a', ('fadd', b, '#c')), ('fadd', ('fadd', a, c), b)),
+ (('iadd', '#a', ('iadd', b, '#c')), ('iadd', ('iadd', a, c), b)),
+
# Misc. lowering
(('fmod', a, b), ('fsub', a, ('fmul', b, ('ffloor', ('fdiv', a, b)))), 'options->lower_fmod'),
(('uadd_carry', a, b), ('b2i', ('ult', ('iadd', a, b), a)), 'options->lower_uadd_carry'),
# they help code generation but do not necessarily produce code that is
# more easily optimizable.
late_optimizations = [
+ # Most of these optimizations aren't quite safe when you get infinity or
+ # Nan involved but the first one should be fine.
(('flt', ('fadd', a, b), 0.0), ('flt', a, ('fneg', b))),
- (('fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
- (('feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
- (('fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
+ (('~fge', ('fadd', a, b), 0.0), ('fge', a, ('fneg', b))),
+ (('~feq', ('fadd', a, b), 0.0), ('feq', a, ('fneg', b))),
+ (('~fne', ('fadd', a, b), 0.0), ('fne', a, ('fneg', b))),
+
(('fdot2', a, b), ('fdot_replicated2', a, b), 'options->fdot_replicates'),
(('fdot3', a, b), ('fdot_replicated3', a, b), 'options->fdot_replicates'),
(('fdot4', a, b), ('fdot_replicated4', a, b), 'options->fdot_replicates'),