mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-07-21 02:29:22 +00:00
792202d090
within a single bit-width of vectors. This is particularly useful for when you know you have bugs in a certain area and want to find simpler test cases than those produced by an open-ended fuzzing that ends up legalizing the vector in addition to shuffling it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@215056 91177308-0d34-0410-b5e6-96231b3b80d8
185 lines
6.4 KiB
Python
Executable File
185 lines
6.4 KiB
Python
Executable File
#!/usr/bin/env python
|
|
|
|
"""A shuffle vector fuzz tester.
|
|
|
|
This is a python program to fuzz test the LLVM shufflevector instruction. It
|
|
generates a function with a random sequnece of shufflevectors, maintaining the
|
|
element mapping accumulated across the function. It then generates a main
|
|
function which calls it with a different value in each element and checks that
|
|
the result matches the expected mapping.
|
|
|
|
Take the output IR printed to stdout, compile it to an executable using whatever
|
|
set of transforms you want to test, and run the program. If it crashes, it found
|
|
a bug.
|
|
"""
|
|
|
|
import argparse
|
|
import itertools
|
|
import random
|
|
import sys
|
|
|
|
def main():
|
|
parser = argparse.ArgumentParser(description=__doc__)
|
|
parser.add_argument('seed',
|
|
help='A string used to seed the RNG')
|
|
parser.add_argument('-v', '--verbose', action='store_true',
|
|
help='Show verbose output')
|
|
parser.add_argument('--fixed-num-shuffles', type=int,
|
|
help='Specify a fixed number of shuffles to test')
|
|
parser.add_argument('--fixed-bit-width', type=int, choices=[128, 256],
|
|
help='Specify a fixed bit width of vector to test')
|
|
parser.add_argument('--triple',
|
|
help='Specify a triple string to include in the IR')
|
|
args = parser.parse_args()
|
|
|
|
random.seed(args.seed)
|
|
|
|
if args.fixed_bit_width is not None:
|
|
if args.fixed_bit_width == 128:
|
|
(width, element_type) = random.choice(
|
|
[(2, 'i64'), (4, 'i32'), (8, 'i16'), (16, 'i8'),
|
|
(2, 'f64'), (4, 'f32')])
|
|
elif args.fixed_bit_width == 256:
|
|
(width, element_type) = random.choice([
|
|
(4, 'i64'), (8, 'i32'), (16, 'i16'), (32, 'i8'),
|
|
(4, 'f64'), (8, 'f32')])
|
|
else:
|
|
sys.exit(1) # Checked above by argument parsing.
|
|
else:
|
|
width = random.choice([2, 4, 8, 16, 32, 64])
|
|
element_type = random.choice(['i8', 'i16', 'i32', 'i64', 'f32', 'f64'])
|
|
|
|
# FIXME: Support blends.
|
|
shuffle_indices = [-1] + range(width)
|
|
|
|
if args.fixed_num_shuffles is not None:
|
|
num_shuffles = args.fixed_num_shuffles
|
|
else:
|
|
num_shuffles = random.randint(0, 16)
|
|
|
|
shuffles = [[random.choice(shuffle_indices)
|
|
for _ in itertools.repeat(None, width)]
|
|
for _ in itertools.repeat(None, num_shuffles)]
|
|
|
|
if args.verbose:
|
|
# Print out the shuffle sequence in a compact form.
|
|
print >>sys.stderr, 'Testing shuffle sequence:'
|
|
for s in shuffles:
|
|
print >>sys.stderr, ' v%d%s: %s' % (width, element_type, s)
|
|
print >>sys.stderr, ''
|
|
|
|
# Compute a round-trip of the shuffle.
|
|
result = range(1, width + 1)
|
|
for s in shuffles:
|
|
result = [result[i] if i != -1 else -1 for i in s]
|
|
|
|
if args.verbose:
|
|
print >>sys.stderr, 'Which transforms:'
|
|
print >>sys.stderr, ' from: %s' % (range(1, width + 1),)
|
|
print >>sys.stderr, ' into: %s' % (result,)
|
|
print >>sys.stderr, ''
|
|
|
|
# The IR uses silly names for floating point types. We also need a same-size
|
|
# integer type.
|
|
integral_element_type = element_type
|
|
if element_type == 'f32':
|
|
integral_element_type = 'i32'
|
|
element_type = 'float'
|
|
elif element_type == 'f64':
|
|
integral_element_type = 'i64'
|
|
element_type = 'double'
|
|
|
|
# Now we need to generate IR for the shuffle function.
|
|
subst = {'N': width, 'T': element_type, 'IT': integral_element_type}
|
|
print """
|
|
define internal <%(N)d x %(T)s> @test(<%(N)d x %(T)s> %%v) noinline nounwind {
|
|
entry:""" % subst
|
|
|
|
for i, s in enumerate(shuffles):
|
|
print """
|
|
%%s%(i)d = shufflevector <%(N)d x %(T)s> %(I)s, <%(N)d x %(T)s> undef, <%(N)d x i32> <%(S)s>
|
|
""".strip() % dict(subst,
|
|
i=i,
|
|
I=('%%s%d' % (i - 1)) if i != 0 else '%v',
|
|
S=', '.join(['i32 %s' % (str(si) if si != -1 else 'undef',)
|
|
for si in s]))
|
|
|
|
print """
|
|
ret <%(N)d x %(T)s> %%s%(i)d
|
|
}
|
|
""" % dict(subst, i=len(shuffles) - 1)
|
|
|
|
# Generate some string constants that we can use to report errors.
|
|
for i, r in enumerate(result):
|
|
if r != -1:
|
|
s = ('FAIL(%(seed)s): lane %(lane)d, expected %(result)d, found %%d\\0A' %
|
|
{'seed': args.seed, 'lane': i, 'result': r})
|
|
s += ''.join(['\\00' for _ in itertools.repeat(None, 64 - len(s) + 2)])
|
|
print """
|
|
@error.%(i)d = private unnamed_addr global [64 x i8] c"%(s)s"
|
|
""".strip() % {'i': i, 's': s}
|
|
|
|
# Finally, generate a main function which will trap if any lanes are mapped
|
|
# incorrectly (in an observable way).
|
|
print """
|
|
define i32 @main() optnone noinline {
|
|
entry:
|
|
; Create a scratch space to print error messages.
|
|
%%str = alloca [64 x i8]
|
|
%%str.ptr = getelementptr inbounds [64 x i8]* %%str, i32 0, i32 0
|
|
|
|
; Build the input vector and call the test function.
|
|
%%input = bitcast <%(N)d x %(IT)s> <%(input)s> to <%(N)d x %(T)s>
|
|
%%v = call <%(N)d x %(T)s> @test(<%(N)d x %(T)s> %%input)
|
|
; We need to cast this back to an integer type vector to easily check the
|
|
; result.
|
|
%%v.cast = bitcast <%(N)d x %(T)s> %%v to <%(N)d x %(IT)s>
|
|
br label %%test.0
|
|
""" % dict(subst,
|
|
input=', '.join(['%(IT)s %(i)s' % dict(subst, i=i)
|
|
for i in xrange(1, width + 1)]),
|
|
result=', '.join(['%(IT)s %(i)s' % dict(subst,
|
|
i=i if i != -1 else 'undef')
|
|
for i in result]))
|
|
|
|
# Test that each non-undef result lane contains the expected value.
|
|
for i, r in enumerate(result):
|
|
if r == -1:
|
|
print """
|
|
test.%(i)d:
|
|
; Skip this lane, its value is undef.
|
|
br label %%test.%(next_i)d
|
|
""" % dict(subst, i=i, next_i=i + 1)
|
|
else:
|
|
print """
|
|
test.%(i)d:
|
|
%%v.%(i)d = extractelement <%(N)d x %(IT)s> %%v.cast, i32 %(i)d
|
|
%%cmp.%(i)d = icmp ne %(IT)s %%v.%(i)d, %(r)d
|
|
br i1 %%cmp.%(i)d, label %%die.%(i)d, label %%test.%(next_i)d
|
|
|
|
die.%(i)d:
|
|
; Capture the actual value and print an error message.
|
|
%%tmp.%(i)d = zext %(IT)s %%v.%(i)d to i2048
|
|
%%bad.%(i)d = trunc i2048 %%tmp.%(i)d to i32
|
|
call i32 (i8*, i8*, ...)* @sprintf(i8* %%str.ptr, i8* getelementptr inbounds ([64 x i8]* @error.%(i)d, i32 0, i32 0), i32 %%bad.%(i)d)
|
|
%%length.%(i)d = call i32 @strlen(i8* %%str.ptr)
|
|
%%size.%(i)d = add i32 %%length.%(i)d, 1
|
|
call i32 @write(i32 2, i8* %%str.ptr, i32 %%size.%(i)d)
|
|
call void @llvm.trap()
|
|
unreachable
|
|
""" % dict(subst, i=i, next_i=i + 1, r=r)
|
|
|
|
print """
|
|
test.%d:
|
|
ret i32 0
|
|
}
|
|
|
|
declare i32 @strlen(i8*)
|
|
declare i32 @write(i32, i8*, i32)
|
|
declare i32 @sprintf(i8*, i8*, ...)
|
|
declare void @llvm.trap() noreturn nounwind
|
|
""" % (len(result),)
|
|
|
|
if __name__ == '__main__':
|
|
main()
|