Piotr Padlewski [Mon, 23 Jan 2017 16:38:10 +0000 (16:38 +0000)]
[MemorySSA] Add new tests for invariant.groups
Summary:
Next round of extra tests for MSSA.
I have a prototype invariant.group handling implementation
that fixes all the FIXMEs, and I think it will be
easier to see what is the difference if I firstly
post this, and then only fix fixits.
Jonas Paulsson [Mon, 23 Jan 2017 14:09:58 +0000 (14:09 +0000)]
[SystemZ] Mark vector immediate load instructions with useful flags.
Vector immediate load instructions should have the isAsCheapAsAMove, isMoveImm
and isReMaterializable flags set. With them, these instruction will get
hoisted out of loops.
Chandler Carruth [Mon, 23 Jan 2017 08:33:29 +0000 (08:33 +0000)]
This test apparently requires an x86 target and is failing on numerous
bots ever since d0k fixed the CHECK lines so that it did something at
all.
It isn't actually testing SCEV directly but LSR, so move it into LSR and
the x86-specific tree of tests that already exists there. Target
dependence is common and unavoidable with the current design of LSR.
Chandler Carruth [Mon, 23 Jan 2017 08:33:24 +0000 (08:33 +0000)]
[PM] Replace the hard invalidate in JumpThreading for LVI with correct
invalidation of deleted functions in GlobalDCE.
This was always testing a bug really triggered in GlobalDCE. Right now
we have analyses with asserting value handles into IR. As long as those
remain, when *deleting* an IR unit, we cannot wait for the normal
invalidation scheme to kick in even though it was designed to work
correctly in the face of these kinds of deletions. Instead, the pass
needs to directly handle invalidating the analysis results pointing at
that IR unit.
I've tought the Inliner about this and this patch teaches GlobalDCE.
This will handle the asserting VH case in the existing test as well as
other issues of the same fundamental variety. I've moved the test into
the GlobalDCE directory and added a comment explaining what is going on.
Note that we cannot simply require LVI here because LVI is too lazy.
Chandler Carruth [Mon, 23 Jan 2017 07:53:20 +0000 (07:53 +0000)]
[PM] Add a dedicated test case for the issue fixed in r292770.
While this is covered by a clang test case, we should have something
locally to LLVM that immediately checks the inliner doesn't leave
analyses to dangling IR bodies.
Chandler Carruth [Mon, 23 Jan 2017 07:03:41 +0000 (07:03 +0000)]
[PM] Clear any analyses for a dead function after inlining it and before
clearing its body. This is essential to avoid triggering asserting value
handles in analyses on the function's body.
I'm working on a test case for this behavior in LLVM, but Clang has
a great one that managed to trigger this on all of the bots already.
Add the `--strip-underscore` option to llvm-cxxfilt to strip the leading
underscore. This is useful for when dealing with targets which add a
leading underscore.
Chandler Carruth [Sun, 22 Jan 2017 10:34:01 +0000 (10:34 +0000)]
[PM] Fix a really nasty bug introduced when adding PGO support to the
new PM's inliner.
The bug happens when we refine an SCC after having computed a proxy for
the FunctionAnalysisManager, and then proceed to compute fresh analyses
for functions in the *new* SCC using the manager provided by the old
SCC's proxy. *And* when we manage to mutate a function in this new SCC
in a way that invalidates those analyses. This can be... challenging to
reproduce.
I've managed to contrive a set of functions that trigger this and added
a test case, but it is a bit brittle. I've directly checked that the
passes run in the expected ways to help avoid the test just becoming
silently irrelevant.
This gets the new PM back to passing the LLVM test suite after the PGO
improvements landed.
Craig Topper [Sun, 22 Jan 2017 06:53:07 +0000 (06:53 +0000)]
[IR] Add LLVM_READONLY to BasicBlock::getTerminator.
I noticed that this function got called twice in compiled code to create succ_begin and succ_end iterators. Adding this directive helps the compiler share the call.
Ideally we'd just make this method available for inlining since its quite simple, but the current header file arrangements don't allow that.
Marcos Pividori [Sun, 22 Jan 2017 02:28:08 +0000 (02:28 +0000)]
[libFuzzer] Fix test with shared libraries on Windows.
We need to set BINARY_DIR to: ${CMAKE_BINARY_DIR}/lib/Fuzzer/test , so the dll
is placed in the same directory than the test LLVMFuzzer-DSOTest, and is found
when executing that test.
As we are using CMAKE_CXX_CREATE_SHARED_LIBRARY to link the dll, we can't modify
the output directory for the import library. It will be created in the same
directory than the dll (in BINARY_DIR), no matter which value we set to
LIBRARY_DIR. So, if we set LIBRARY_DIR to a different directory than BINARY_DIR,
when linking LLVMFuzzer-DSOTest, cmake will look for the import library
LLVMFuzzer-DSO1.lib in LIBRARY_DIR, and won't find it, since it was created in
BINARY_DIR. So, for Windows, we need that LIBRARY_DIR and BINARY_DIR are the
same directory.
Marcos Pividori [Sun, 22 Jan 2017 01:58:59 +0000 (01:58 +0000)]
[libFuzzer] AlrmHandler is executed in a different thread for Windows.
Don't check for InFuzzingThread() on Windows, since the AlarmHandler() is
always executed by a different thread from a thread pool.
If we don't add these changes, the alarm handler will never execute.
Note that we decided to ignore possible problem in the synchronization.
Marcos Pividori [Sun, 22 Jan 2017 01:58:50 +0000 (01:58 +0000)]
[libFuzzer] Fix OutOfMemory tests to work on 32 bits.
I add 2 changes to make the tests work on 32 bits and on 64 bits.
I change the size allocated to 0x20000000 and add the flag: -rss_limit_mb=300.
Otherwise the output for 32 bits and 64 bits is different.
For 64 bits the value 0xff000000 doesn't exceed kMaxAllowedMallocSize.
For 32 bits, kMaxAllowedMallocSize is set to 0xc0000000, so the call to
Allocate() will fail earlier printing "WARNING: AddressSanitizer failed to
allocate ..." , and wont't call malloc hooks.
So, we need to consider a size smaller than 2GB (so malloc doesn't fail on
32bits) and greater that the value provided by -rss_limit_mb.
Because of that I use: 0x20000000.
Marcos Pividori [Sun, 22 Jan 2017 01:58:45 +0000 (01:58 +0000)]
[libFuzzer] Avoid undefined behavior, properly discard output to stdout/stderr.
Fix libFuzzer when setting -close_fd_mask to a non-zero value.
In previous implementation, libFuzzer closes the file descriptors for
stdout/stderr. This has some disavantages:
For `fuzzer-fdmask.test`, we write directly to stdout and stderr using the
file streams stdout and stderr, after the file descriptors are closed, which is
undefined behavior. In Windows, in particular, this was making the test fail.
Also, if we close stdout and we open a new file in libFuzzer, we get the file
descriptor 1, which could generate problem if some code assumes file descriptors
refers to stdout and works directly writing to the file descriptor 1, but it
will be writing to the opened file (for example using std::cout).
Instead of closing the file descriptors, I redirect the output to /dev/null on
linux and nul on Windows.
Marcos Pividori [Sun, 22 Jan 2017 01:58:36 +0000 (01:58 +0000)]
[libFuzzer] Fix ListFilesInDirRecursive() to do the same for Posix and Windows.
Update `ListFilesInDirRecursive` implementation on Windows to have the same
behavior than for Posix, when the directory doesn't exists and when it is empty.
Marcos Pividori [Sun, 22 Jan 2017 01:58:26 +0000 (01:58 +0000)]
[libFuzzer] Portably disassemble and find calls to sanitizer_cov_trace_pc_guard.
Instead of directly using objdump, which is not present on Windows, we consider
different tools depending on the platform.
For Windows, we consider dumpbin and llvm-objdump.
Marcos Pividori [Sun, 22 Jan 2017 01:27:42 +0000 (01:27 +0000)]
[libFuzzer] Remove optimization flags for tests.
We need to build all the tests with -O0, otherwise optimizations may merge some
basic blocks and the tests will fail.
In this diff, I simplify the cmake implementation and I remove the flags for
Windows too (/O[123s]).
Marcos Pividori [Sun, 22 Jan 2017 01:27:34 +0000 (01:27 +0000)]
[libFuzzer] Remove dependencies for tests on Windows.
Remove dependency on FileCheck, sancov and not for tests on Windows.
If LLVM_USE_SANITIZER=Address and LLVM_USE_SANITIZE_COVERAGE=YES, this will
trigger the building of dependencies with sanitizer instrumentation.
This will fail in Windows, since cmake will use link.exe for linking and won't
include compiler-rt libraries.
Sanjay Patel [Sat, 21 Jan 2017 17:51:25 +0000 (17:51 +0000)]
[ValueTracking] tighten up matchMinMax(); NFCI
This is similar to what the caller (matchSelectPattern()) does. In all
cases where we succeed in matching a min/max pattern, the values in
that pattern will be the values of the 'select', so hoist that and
remove a bunch of duplicated code.
Chandler Carruth [Sat, 21 Jan 2017 04:16:53 +0000 (04:16 +0000)]
[PM] Sink an LCSSA preservation assert from the LoopSimplify pass into
the library routine shared with the new PM and other code.
This assert checks that when LCSSA preservation is requested we start in
LCSSA form. Without this early assert, given *very* complex test cases
we can hit an assert or crash much later on when trying to preserve
LCSSA.
The new PM's loop simplify doesn't need to (and indeed can't) preserve
LCSSA as the new PM doesn't deal in transforms in the dependency graph.
But we asked the library to and shockingly, this didn't work very well!
Stop doing that. Now the assert will tell us immediately with existing
test cases. Before this, it took a pretty convoluted input to trigger
this.
However, sinking the assert also found a bug in LoopUnroll where we
asked simplifyLoop to preserve LCSSA *right before we reform it*. That's
kinda silly and unsurprising that it wasn't available. =D Stop doing
that too.
We also would assert that the unrolled loop was in LCSSA even if
preserving LCSSA was never requested! I don't have a test case or
anything here. I spotted it by inspection and it seems quite obvious. No
logic change anyways, that's just avoiding a spurrious assert.
Chandler Carruth [Sat, 21 Jan 2017 03:48:51 +0000 (03:48 +0000)]
[PM] Teach the loop PM to run LoopSimplify prior to the loop pipeline.
This adds the last remaining core feature of the loop pass pipeline in
the new PM and removes the last of the really egregious hacks in the
LICM tests.
Sadly, this requires really substantial changes in the unittests in
order to provide and maintain simplified loops. This is particularly
hard because for example LoopSimplify will try to fold undef branches to
an ideal direction and simplify the loop accordingly.
This is a stub implementation of the `-s` or `--format` option that
allows the user to specify the demangling style. Since we only support
the Itanium (GNU) style demangling, auto is synonymous with `gnu`.
Simply swallow the option to permit some level of commandline
compatibility.
MergeFunctions: Preserve debug info in thunks, under option -mergefunc-preserve-debug-info
Summary:
Under option -mergefunc-preserve-debug-info we:
- Do not create a new function for a thunk.
- Retain the debug info for a thunk's parameters (and associated
instructions for the debug info) from the entry block.
Note: -debug will display the algorithm at work.
- Create debug-info for the call (to the shared implementation) made by
a thunk and its return value.
- Erase the rest of the function, retaining the (minimally sized) entry
block to create a thunk.
- Preserve a thunk's call site to point to the thunk even when both occur
within the same translation unit, to aid debugability. Note that this
behaviour differs from the underlying -mergefunc implementation which
modifies the thunk's call site to point to the shared implementation
when both occur within the same translation unit.
Justin Lebar [Sat, 21 Jan 2017 00:59:57 +0000 (00:59 +0000)]
[ConstantFolding] Constant-fold llvm.sqrt(x) like other intrinsics.
Summary:
Currently we return undef, but we're in the process of changing the
LangRef so that llvm.sqrt behaves like the other math intrinsics,
matching the return value of the standard libcall but not setting errno.
This change is legal even without the LangRef change because currently
calling llvm.sqrt(x) where x is negative is spec'ed to be UB. But in
practice it's also safe because we're simply constant-folding fewer
inputs: Inputs >= -0 get constant-folded as before, but inputs < -0 now
aren't constant-folded, because ConstantFoldFP aborts if the host math
function raises an fp exception.
Guozhi Wei [Fri, 20 Jan 2017 23:35:27 +0000 (23:35 +0000)]
[PPC] Give unaligned memory access lower cost on processor that supports it
Newer ppc supports unaligned memory access, it reduces the cost of unaligned memory access significantly. This patch handles this case in PPCTTIImpl::getMemoryOpCost.
Davide Italiano [Fri, 20 Jan 2017 23:29:28 +0000 (23:29 +0000)]
[NewGVN] Optimize processing for instructions found trivially dead.
Don't call `isTriviallyDeadInstructions()` once we discover that
an instruction is dead. Instead, set DFS number zero (as suggested
by Danny) and forget about it (this also speeds up things as we
won't try to reprocess that block).
Tim Northover [Fri, 20 Jan 2017 23:25:17 +0000 (23:25 +0000)]
GlobalISel: prevent heap use-after-free when looking up VReg.
Translating the constant can create more VRegs, which can invalidate the
reference into the DenseMap. So we have to look up the value again after all
that's happened.
Marcos Pividori [Fri, 20 Jan 2017 22:49:08 +0000 (22:49 +0000)]
[libFuzzer] Use clang as linker on Windows, to properly include sanitizer libraries.
In order to use sanitizers on Windows, we need to link against many runtime
libraries which will depend on the target being created (executable or dll) and
the c runtime library used (MT/MD).
By default, cmake uses link.exe for linking, which fails because we don't
specify the appropiate dependencies. As we don't want to consider all of that
possible situations which depends on the implementation of the compiler-rt, the
simplest option is to change the rules for linking executables and shared
libraries, using the compiler instead of link.exe.
Clang driver will consider the sanitizer flags, and automatically provide the
required libraries to the linker.