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| author | Alon Zakai <azakai@google.com> | 2020-10-21 09:03:56 -0700 |
|---|---|---|
| committer | GitHub <noreply@github.com> | 2020-10-21 09:03:56 -0700 |
| commit | b7c452ea1bf0ebce9f8da19e8124c20b4373a009 (patch) | |
| tree | 575bc5ede60ffdad8fc3c71cda5c1478ae74279b /src/tools/fuzzing.h | |
| parent | fd4cfd180db4d8c9b2b99dca18e31763399b4702 (diff) | |
| download | binaryen-b7c452ea1bf0ebce9f8da19e8124c20b4373a009.tar.gz binaryen-b7c452ea1bf0ebce9f8da19e8124c20b4373a009.tar.bz2 binaryen-b7c452ea1bf0ebce9f8da19e8124c20b4373a009.zip | |
Fuzzer: Tweak constants during mutation as well (#3272)
Move the tweak function to an outer location, and call it from mutate() with
some probability.
Diffstat (limited to 'src/tools/fuzzing.h')
| -rw-r--r-- | src/tools/fuzzing.h | 80 |
1 files changed, 47 insertions, 33 deletions
diff --git a/src/tools/fuzzing.h b/src/tools/fuzzing.h index d2cdb7a7f..36cf1fb42 100644 --- a/src/tools/fuzzing.h +++ b/src/tools/fuzzing.h @@ -675,7 +675,16 @@ private: void visitExpression(Expression* curr) { if (parent.oneIn(10)) { - // Replace it! + // For constants, perform only a small tweaking in some cases. + if (auto* c = curr->dynCast<Const>()) { + if (parent.oneIn(2)) { + c->value = parent.tweak(c->value); + return; + } + } + // TODO: more minor tweaks to immediates, like making a load atomic or + // not, changing an offset, etc. + // Perform a general replacement. // (This is not always valid due to nesting of labels, but // we'll fix that up later.) replaceCurrent(parent.make(curr->type)); @@ -1536,6 +1545,43 @@ private: return store; } + // Makes a small change to a constant value. + Literal tweak(Literal value) { + auto type = value.type; + if (type.isVector()) { + // TODO: tweak each lane? + return value; + } + // +- 1 + switch (upTo(5)) { + case 0: + value = value.add(Literal::makeNegOne(type)); + break; + case 1: + value = value.add(Literal::makeOne(type)); + break; + default: { + } + } + // For floats, optionally add a non-integer adjustment in +- [-1, 1] + if (type.isFloat() && oneIn(2)) { + const int RANGE = 1000; + auto RANGE_LITERAL = Literal::makeFromInt32(RANGE, type); + // adjustment -> [0, 2 * RANGE] + auto adjustment = Literal::makeFromInt32(upTo(2 * RANGE + 1), type); + // adjustment -> [-RANGE, RANGE] + adjustment = adjustment.sub(RANGE_LITERAL); + // adjustment -> [-1, 1] + adjustment = adjustment.div(RANGE_LITERAL); + value = value.add(adjustment); + } + // Flip sign. + if (oneIn(2)) { + value = value.mul(Literal::makeNegOne(type)); + } + return value; + } + Literal makeLiteral(Type type) { if (type == Type::v128) { // generate each lane individually for random lane interpretation @@ -1587,38 +1633,6 @@ private: } } - // Optional tweaking of the value by a small adjustment. - auto tweak = [this, type](Literal value) { - // +- 1 - switch (upTo(5)) { - case 0: - value = value.add(Literal::makeNegOne(type)); - break; - case 1: - value = value.add(Literal::makeOne(type)); - break; - default: { - } - } - // For floats, optionally add a non-integer adjustment in +- [-1, 1] - if (type.isFloat() && oneIn(2)) { - const int RANGE = 1000; - auto RANGE_LITERAL = Literal::makeFromInt32(RANGE, type); - // adjustment -> [0, 2 * RANGE] - auto adjustment = Literal::makeFromInt32(upTo(2 * RANGE + 1), type); - // adjustment -> [-RANGE, RANGE] - adjustment = adjustment.sub(RANGE_LITERAL); - // adjustment -> [-1, 1] - adjustment = adjustment.div(RANGE_LITERAL); - value = value.add(adjustment); - } - // Flip sign. - if (oneIn(2)) { - value = value.mul(Literal::makeNegOne(type)); - } - return value; - }; - switch (upTo(4)) { case 0: { // totally random, entire range |