This expands the lookup table statically and avoids routing through methods that
contain asserts (like StringRef/std::string element accessors and drop_front)
such that performance is more predictable across compilation environments. This
was primarily driven by slow debug mode performance but has a large benefit in
release builds as well.
```
ssd_mobilenet_v2_face_float (42MB .mlir)
Debug/MSVC (old): 5.22s
Debug/MSVC (new): 0.16s
Release/MSVC (old): 0.81s
Release/MSVC (new): 0.02s
huggingface_minilm (536MB .mlir)
Debug/MSVC (old): 65.31s
Debug/MSVC (new): 2.03s
Release/MSVC (old): 9.93s
Release/MSVC (new): 0.27s
```
Now in debug the time is split evenly between lexString, tryGetFromHex, and
element attrs hashing, with the next step to making it faster being to combine
the work (incremental hashing during conversion, etc) - but this is at least in
the right order of magnitude and retains the original API surface.
I have not profiled a build with clang but this is strictly less code and simpler
data structures so I'd expect improvements there as well.
This also fixes a bug where 0xFF bytes in the input would read out of bounds.
Reviewed By: dblaikie, stellaraccident
Differential Revision: https://reviews.llvm.org/D112105
Optimize the iterator comparison logic to compare Current.data()
pointers. Use std::tie for assignments from std::pair. Replace
the custom class with a function returning iterator_range.
Differential Revision: https://reviews.llvm.org/D110535
Add a llvm::Split() implementation that can be used via range-for loop,
e.g.:
for (StringRef x : llvm::Split("foo,bar,baz", ','))
...
The implementation uses an additional SplittingIterator class that
uses StringRef::split() internally.
Differential Revision: https://reviews.llvm.org/D110496
<string> is currently the highest impact header in a clang+llvm build:
https://commondatastorage.googleapis.com/chromium-browser-clang/llvm-include-analysis.html
One of the most common places this is being included is the APInt.h header, which needs it for an old toString() implementation that returns std::string - an inefficient method compared to the SmallString versions that it actually wraps.
This patch replaces these APInt/APSInt methods with a pair of llvm::toString() helpers inside StringExtras.h, adjusts users accordingly and removes the <string> from APInt.h - I was hoping that more of these users could be converted to use the SmallString methods, but it appears that most end up creating a std::string anyhow. I avoided trying to use the raw_ostream << operators as well as I didn't want to lose having the integer radix explicit in the code.
Differential Revision: https://reviews.llvm.org/D103888
This patch introduces a helper class SubsequentDelim to simplify loops
that generate a comma-separated lists.
For example, consider the following loop, taken from
llvm/lib/CodeGen/MachineBasicBlock.cpp:
for (auto I = pred_begin(), E = pred_end(); I != E; ++I) {
if (I != pred_begin())
OS << ", ";
OS << printMBBReference(**I);
}
The new class allows us to rewrite the loop as:
SubsequentDelim SD;
for (auto I = pred_begin(), E = pred_end(); I != E; ++I)
OS << SD << printMBBReference(**I);
where SD evaluates to the empty string for the first time and ", " for
subsequent iterations.
Unlike interleaveComma, defined in llvm/include/llvm/ADT/STLExtras.h,
SubsequentDelim can accommodate a wider variety of loops, including:
- those that conditionally skip certain items,
- those that need iterators to call getSuccProbability(I), and
- those that iterate over integer ranges.
As an example, this patch cleans up MachineBasicBlock::print.
Differential Revision: https://reviews.llvm.org/D94377
This revision adds a fail-able/checked version of `fromHex` that fails when the input string contains a non-hex character. This removes the need for users to have a separate check for if the string contains all hex digits. This becomes very costly for large hex strings given that checking if a string contains only hex digits is effectively the same as just converting it in the first place.
Context: In MLIR we use hex strings to represent very large constants in the textual format of the IR. These changes lead to a large decrease in compile time when parsing these constants (2 seconds -> 1 second).
Differential Revision: https://reviews.llvm.org/D90265
Summary:
This revision adds two utilities currently present in MLIR to LLVM StringExtras:
* convertToSnakeFromCamelCase
Convert a string from a camel case naming scheme, to a snake case scheme
* convertToCamelFromSnakeCase
Convert a string from a snake case naming scheme, to a camel case scheme
Differential Revision: https://reviews.llvm.org/D78167
This improves readability of Windows path string literals in LLVM IR.
The LLVM assembler has supported \\ in IR strings for a long time, but
the lexer doesn't tolerate escaped quotes, so they have to be printed as
\22 for now.
llvm-svn: 374415
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
The standard library functions ::isprint/std::isprint have platform-
and locale-dependent behavior which makes LLVM's output less
predictable. In particular, regression tests my fail depending on the
implementation of these functions.
Implement llvm::isPrint in StringExtras.h with a standard behavior and
replace all uses of ::isprint/std::isprint by a call it llvm::isPrint.
The function is inlined and does not look up language settings so it
should perform better than the standard library's version.
Such a replacement has already been done for isdigit, isalpha, isxdigit
in r314883. gtest does the same in gtest-printers.cc using the following
justification:
// Returns true if c is a printable ASCII character. We test the
// value of c directly instead of calling isprint(), which is buggy on
// Windows Mobile.
inline bool IsPrintableAscii(wchar_t c) {
return 0x20 <= c && c <= 0x7E;
}
Similar issues have also been encountered by Julia:
https://github.com/JuliaLang/julia/issues/7416
I noticed the problem myself when on Windows isprint('\t') started to
evaluate to true (see https://stackoverflow.com/questions/51435249) and
thus caused several unit tests to fail. The result of isprint doesn't
seem to be well-defined even for ASCII characters. Therefore I suggest
to replace isprint by a platform-independent version.
Differential Revision: https://reviews.llvm.org/D49680
llvm-svn: 338034
As noted by Adrian on llvm-commits, PrintHTMLEscaped and PrintEscaped in
StringExtras did not conform to the LLVM coding guidelines. This commit
rectifies that.
llvm-svn: 333669
Summary:
The function matches the interface of llvm::to_integer, but as we are
calling out to a C library function, I let it take a Twine argument, so
we can avoid a string copy at least in some cases.
I add a test and replace a couple of existing uses of strtod with this
function.
Reviewers: zturner
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34518
llvm-svn: 306096
We already have a function toHex that will convert a string like
"\xFF\xFF" to the string "FFFF", but we do not have one that goes
the other way - i.e. to convert a textual string representing a
sequence of hexadecimal characters into the corresponding actual
bytes. This patch adds such a function.
llvm-svn: 301356
llvm::join_items is similar to llvm::join, which produces a string
by concatenating a sequence of values together separated by a
given separator. But it differs in that the arguments to
llvm::join() are same-type members of a container, whereas the
arguments to llvm::join_items are arbitrary types passed into
a variadic template. The only requirement on parameters to
llvm::join_items (including for the separator themselves) is
that they be implicitly convertible to std::string or have
an overload of std::string::operator+
Differential Revision: https://reviews.llvm.org/D24880
llvm-svn: 282502
Yuanfang Chen