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Differential D50484

[libFuzzer] Increase the iteration limit in shrink.test
ClosedPublic

Authored by george.karpenkov on Aug 8 2018, 5:39 PM.

Details

Reviewers
kcc
morehouse
vitalybuka
Commits
rG8389196dd978: Merging r339303: --------------------------------------------------------------…
rG67d858d5e46b: [libFuzzer] Increase the iteration limit in shrink.test
rL339315: Merging r339303:
rCRT339303: [libFuzzer] Increase the iteration limit in shrink.test
rL339303: [libFuzzer] Increase the iteration limit in shrink.test
Summary

After https://reviews.llvm.org/D48800, shrink.test started failing on x86_64h architecture.
Looking into this, the optimization pass is too eager to unroll the loop on x86_64h, possibly leading to worse coverage data.

Alternative solutions include not unrolling the loop when fuzzing, or disabling this test on that architecture.

Diff Detail

Repository
rL LLVM

Event Timeline

george.karpenkov created this revision.Aug 8 2018, 5:39 PM
Herald added a subscriber: dmgreen. · View Herald TranscriptAug 8 2018, 5:39 PM
morehouse accepted this revision.Aug 8 2018, 5:40 PM
This revision is now accepted and ready to land.Aug 8 2018, 5:40 PM
Closed by commit rL339303: [libFuzzer] Increase the iteration limit in shrink.test (authored by george.karpenkov). · Explain WhyAug 8 2018, 5:42 PM
This revision was automatically updated to reflect the committed changes.
Herald added subscribers: llvm-commits, delcypher. · View Herald TranscriptAug 8 2018, 5:42 PM

Revision Contents

PathSize
compiler-rt/
trunk/
test/
fuzzer/
2 lines

Diff 159837

compiler-rt/trunk/test/fuzzer/shrink.test

RUN: %cpp_compiler %S/ShrinkControlFlowTest.cpp -o %t-ShrinkControlFlowTest RUN: %cpp_compiler %S/ShrinkControlFlowTest.cpp -o %t-ShrinkControlFlowTest
RUN: %cpp_compiler %S/ShrinkValueProfileTest.cpp -o %t-ShrinkValueProfileTest RUN: %cpp_compiler %S/ShrinkValueProfileTest.cpp -o %t-ShrinkValueProfileTest
RUN: %run %t-ShrinkControlFlowTest -seed=1 -exit_on_item=0eb8e4ed029b774d80f2b66408203801cb982a60 -runs=1000000 -shrink=1 -reduce_inputs=0 2>&1 | FileCheck %s --check-prefix=SHRINK1 RUN: %run %t-ShrinkControlFlowTest -seed=1 -exit_on_item=0eb8e4ed029b774d80f2b66408203801cb982a60 -runs=2000000 -shrink=1 -reduce_inputs=0 2>&1 | FileCheck %s --check-prefix=SHRINK1
# Limit max_len to run this negative test faster. # Limit max_len to run this negative test faster.
RUN: %run %t-ShrinkControlFlowTest -seed=1 -exit_on_item=0eb8e4ed029b774d80f2b66408203801cb982a60 -runs=1000000 -shrink=0 -reduce_inputs=0 -max_len=64 2>&1 | FileCheck %s --check-prefix=SHRINK0 RUN: %run %t-ShrinkControlFlowTest -seed=1 -exit_on_item=0eb8e4ed029b774d80f2b66408203801cb982a60 -runs=1000000 -shrink=0 -reduce_inputs=0 -max_len=64 2>&1 | FileCheck %s --check-prefix=SHRINK0
RUN: %run %t-ShrinkValueProfileTest -seed=1 -exit_on_item=aea2e3923af219a8956f626558ef32f30a914ebc -runs=100000 -shrink=1 -reduce_inputs=0 -use_value_profile=1 2>&1 | FileCheck %s --check-prefix=SHRINK1_VP RUN: %run %t-ShrinkValueProfileTest -seed=1 -exit_on_item=aea2e3923af219a8956f626558ef32f30a914ebc -runs=100000 -shrink=1 -reduce_inputs=0 -use_value_profile=1 2>&1 | FileCheck %s --check-prefix=SHRINK1_VP
SHRINK0: Done 1000000 runs in SHRINK0: Done 1000000 runs in
SHRINK1: INFO: found item with checksum '0eb8e4ed029b774d80f2b66408203801cb982a60', exiting. SHRINK1: INFO: found item with checksum '0eb8e4ed029b774d80f2b66408203801cb982a60', exiting.
SHRINK1_VP: INFO: found item with checksum 'aea2e3923af219a8956f626558ef32f30a914ebc', exiting SHRINK1_VP: INFO: found item with checksum 'aea2e3923af219a8956f626558ef32f30a914ebc', exiting