Craig Topper [Wed, 19 Oct 2016 04:44:17 +0000 (04:44 +0000)]
[AVX-512] Teach isel lowering that a subvector broadcast being inserted into both halves of a 512-bit vector can be combined into a larger subvector broadcast.
Summary:
This allows us to create broadcasts of 128-bit vector loads into 512-bit vectors.
New patterns added to support 8-bit and 16-bit vector types and v2f64/v2i64->v8f64/v8i64 without DQI instructions.
There also fallback patterns when the load can't be folded. These patterns are a little complex as we first need to insert the lower 128-bits into the second 128-bits using a zmm subvector insert instruction. We need to use a zmm insert in case VLX isn't available. Then use another zmm sub vector insert to take those 256-bits and insert them into the upper bits. Since we used a zmm insert to create the 256-bits we also need to do a extract_subreg to get just the lower 256-bits to pass to the second insert.
The outer insert for the fallback patterns should have its type correct because eventually we should also supported masked operations here too. So we need a DQI and a NoDQI version of the v16f32/v16i32 patterns.
[libFuzzer] extend -print_coverage to also print uncovered lines, functions, and files.
Example of output:
COVERAGE:
COVERED: in DSO2(int) /pathto/DSO2.cpp:6
COVERED: in DSO2(int) /pathto/DSO2.cpp:8
COVERED: in DSO1(int) /pathto/DSO1.cpp:6
COVERED: in DSO1(int) /pathto/DSO1.cpp:8
COVERED: in LLVMFuzzerTestOneInput /pathto/DSOTestMain.cpp:16
COVERED: in LLVMFuzzerTestOneInput /pathto/DSOTestMain.cpp:19
COVERED: in LLVMFuzzerTestOneInput /pathto/DSOTestMain.cpp:25
COVERED: in LLVMFuzzerTestOneInput /pathto/DSOTestMain.cpp:26
MODULE_WITH_COVERAGE: /pathto/libLLVMFuzzer-DSO1.so
UNCOVERED_LINE: in DSO1(int) /pathto/DSO1.cpp:9
UNCOVERED_FUNC: in Uncovered1()
MODULE_WITH_COVERAGE: /pathto/libLLVMFuzzer-DSO2.so
UNCOVERED_LINE: in DSO2(int) /pathto/DSO2.cpp:9
UNCOVERED_FUNC: in Uncovered2()
MODULE_WITH_COVERAGE: /pathto/LLVMFuzzer-DSOTest
UNCOVERED_LINE: in LLVMFuzzerTestOneInput /pathto/DSOTestMain.cpp:21
UNCOVERED_LINE: in LLVMFuzzerTestOneInput /pathto/DSOTestMain.cpp:27
UNCOVERED_FILE: /pathto/DSOTestExtra.cpp
Several things are not perfect here:
* we are using objdump+awk instead of sancov because sancov does not support DSOs yet.
* this breaks in the presence of ASAN_OPTIONS=strip_path_prefix=...
(need to implement another API to get the module name by PC)
Dehao Chen [Tue, 18 Oct 2016 23:24:02 +0000 (23:24 +0000)]
Using branch probability to guide critical edge splitting.
Summary:
The original heuristic to break critical edge during machine sink is relatively conservertive: when there is only one instruction sinkable to the critical edge, it is likely that the machine sink pass will not break the critical edge. This leads to many speculative instructions executed at runtime. However, with profile info, we could model the splitting benefits: if the critical edge has 50% taken rate, it would always be beneficial to split the critical edge to avoid the speculated runtime instructions. This patch uses profile to guide critical edge splitting in machine sink pass.
The performance impact on speccpu2006 on Intel sandybridge machines:
Rong Xu [Tue, 18 Oct 2016 21:36:27 +0000 (21:36 +0000)]
Conditionally eliminate library calls where the result value is not used
Summary:
This pass shrink-wraps a condition to some library calls where the call
result is not used. For example:
sqrt(val);
is transformed to
if (val < 0)
sqrt(val);
Even if the result of library call is not being used, the compiler cannot
safely delete the call because the function can set errno on error
conditions.
Note in many functions, the error condition solely depends on the incoming
parameter. In this optimization, we can generate the condition can lead to
the errno to shrink-wrap the call. Since the chances of hitting the error
condition is low, the runtime call is effectively eliminated.
These partially dead calls are usually results of C++ abstraction penalty
exposed by inlining. This optimization hits 108 times in 19 C/C++ programs
in SPEC2006.
Dehao Chen [Tue, 18 Oct 2016 21:36:11 +0000 (21:36 +0000)]
Using branch probability to guide critical edge splitting.
Summary:
The original heuristic to break critical edge during machine sink is relatively conservertive: when there is only one instruction sinkable to the critical edge, it is likely that the machine sink pass will not break the critical edge. This leads to many speculative instructions executed at runtime. However, with profile info, we could model the splitting benefits: if the critical edge has 50% taken rate, it would always be beneficial to split the critical edge to avoid the speculated runtime instructions. This patch uses profile to guide critical edge splitting in machine sink pass.
The performance impact on speccpu2006 on Intel sandybridge machines:
David Blaikie [Tue, 18 Oct 2016 21:09:48 +0000 (21:09 +0000)]
dwarfdump: -summarize-types: print a short summary (unqualified type name, hash, length) of type units rather than dumping contents
This is just a quick utility handy for getting rough summaries of types
in a given object or dwo file. I've been using it to investigate the
amount of type info redundancy across a project build, for example.
Dehao Chen [Tue, 18 Oct 2016 20:42:47 +0000 (20:42 +0000)]
Use profile info to set function section prefix to group hot/cold functions.
Summary:
The original implementation is in r261607, which was reverted in r269726 to accomendate the ProfileSummaryInfo analysis pass. The new implementation:
1. add a new metadata for function section prefix
2. query against ProfileSummaryInfo in CGP to set the correct section prefix for each function
3. output the section prefix set by CGP
Evandro Menezes [Tue, 18 Oct 2016 20:37:35 +0000 (20:37 +0000)]
[AArch64] Avoid materializing 0.0 when generating FP SELECT
Transform `a == 0.0 ? 0.0 : x` to `a == 0.0 ? a : x` and `a != 0.0 ? x : 0.0`
to `a != 0.0 ? x : a` to avoid materializing 0.0 for FCSEL, since it does not
have to be materialized beforehand for FCMP, as it has a form that has 0.0
as an implicit operand.
Kevin Enderby [Tue, 18 Oct 2016 20:24:12 +0000 (20:24 +0000)]
One more additional error check for invalid Mach-O files for a
load command that use the MachO:: linkedit_data_command
type but is not used in llvm libObject code but used in llvm tool code.
Tim Northover [Tue, 18 Oct 2016 20:03:48 +0000 (20:03 +0000)]
GlobalISel: select small binary operations on AArch64.
AArch64 actually supports many 8-bit operations under the definition used by
GlobalISel: the designated information-carrying bits of a GPR32 get the right
value if you just use the normal 32-bit instruction.
Simon Pilgrim [Tue, 18 Oct 2016 19:28:12 +0000 (19:28 +0000)]
[X86][SSE] Added vector lshr/shl combine tests
This doesn't cover all combines in DAGCombiner::visitSRL/visitSHL yet, but identifies several cases where we fail to combine vectors (or non-splatted) vectors
Kevin Enderby [Tue, 18 Oct 2016 17:54:17 +0000 (17:54 +0000)]
Next set of additional error checks for invalid Mach-O files for the
load commands that use the MachO::routines_command and
and MachO::routines_command_64 types but are not used in llvm
libObject code but used in llvm tool code.
This includes the LC_ROUTINES and LC_ROUTINES_64
load commands.
Teresa Johnson [Tue, 18 Oct 2016 17:17:37 +0000 (17:17 +0000)]
[docs] Increase minimum supported GCC version for building LLVM to 4.8
Summary:
The RFC proposal sent to increase the minimum required GCC version
to 4.8 received a lot of support. See the following thread:
http://lists.llvm.org/pipermail/llvm-dev/2016-October/105955.html,
This patch implements that by updating the docs. I believe the
references to libstdc++ 4.7 issues can be removed as well, please
let me know if that is not the case or if they should be updated
a different way.
This is a follow-up to D24816 - where we changed reciprocal estimates to be function attributes
rather than TargetOptions.
This patch is intended to be a structural, but not functional change. By moving all of the
TargetRecip functionality into TargetLowering, we can remove all of the reciprocal estimate
state, shield the callers from the string format implementation, and simplify/localize the
logic needed for a target to enable this.
If a function has a "reciprocal-estimates" attribute, those settings may override the target's
default reciprocal preferences for whatever operation and data type we're trying to optimize.
If there's no attribute string or specific setting for the op/type pair, just use the target
default settings.
As noted earlier, a better solution would be to move the reciprocal estimate settings to IR
instructions and SDNodes rather than function attributes, but that's a multi-step job that
requires infrastructure improvements. I intend to work on that, but it's not clear how long
it will take to get all the pieces in place.
Adrian Prantl [Tue, 18 Oct 2016 16:24:43 +0000 (16:24 +0000)]
Disable fatal errors in the Verifier instantiated by bugpoint's crash
debugger.
When bugpoint hacks at a testcase it may at one point create illegal
debug info metadata that won't even pass the Verifier. A bugpoint
*driver* built with assertions should not assert on it, but reject the
malformed intermediate step and continue to do its job.
Simon Dardis [Tue, 18 Oct 2016 15:17:17 +0000 (15:17 +0000)]
[mips][ias] Handle more complicated expressions for memory operands
This patch teaches ias for mips to handle expressions such as
(8*4)+(8*31)($sp). Such expression typically occur from the expansion
of multiple macro definitions.
Simon Dardis [Tue, 18 Oct 2016 14:42:13 +0000 (14:42 +0000)]
[mips] Fix sync instruction definition
The 'sync' instruction for MIPS was defined in MIPS-II as taking no operands.
MIPS32 extended the define of 'sync' as taking an optional unsigned 5 bit
immediate.
This patch correct the definition of sync so that it is accepted with an
operand of 0 or no operand for MIPS-II to MIPS-V, and a 5 bit unsigned
immediate for MIPS32 and later revisions.
Additionally a clear error is given when the MIPS32 version of sync is
used when targeting pre MIPS32.
This partially resolves PR/30714.
Thanks to Daniel Sanders for reporting this issue!
Victor Leschuk [Tue, 18 Oct 2016 14:31:22 +0000 (14:31 +0000)]
DebugInfo: change alignment type from uint64_t to uint32_t to save space.
In futher patches we shall have alignment field added to DIVariable family
and switching from uint64_t to uint32_t will save 4 bytes per variable.
Simon Dardis [Tue, 18 Oct 2016 14:28:00 +0000 (14:28 +0000)]
[mips] Macro expansion for ld, sd for O32
ld and sd when assembled for the O32 ABI expand to a pair of 32 bit word loads
or stores using the specified source or destination register and the next
register.
This patch does not add support for the cases where the offset is greater than
a 16 bit signed immediate as that would lead to a wrong/misleading error
message as the assembler would report "instruction requires a CPU feature
not currently enabled" for ld & sd for MIPS64 when their offset is not a signed
16 bit number.
[x86][inline-asm][avx512] allow swapping of '{k<num>}' & '{z}' marks
Committing on behalf of Coby Tayree: After check-all and LGTM
Desc:
AVX512 allows dest operand to be followed by an op-mask register specifier ('{k<num>}', which in turn may be followed by a merging/zeroing specifier ('{z}')
Currently, the following forms are allowed:
{k<num>}
{k<num>}{z}
This patch allows the following forms:
{z}{k<num>}
[mips][FastISel] Instantiate the MipsFastISel class only for targets that support FastISel.
Summary:
Instead of instantiating the MipsFastISel class and checking if the
target is supported in the overriden methods, we should perform that
check before creating the class. This allows us to enable FastISel *only*
for targets that truly support it, ie. MIPS32 to MIPS32R5.
John Brawn [Tue, 18 Oct 2016 10:10:53 +0000 (10:10 +0000)]
[SCEV] More accurate calculation of max backedge count of some less-than loops
In loops that look something like
i = n;
do {
...
} while(i++ < n+k);
where k is a constant, the maximum backedge count is k (in fact the backedge
count will be either 0 or k, depending on whether n+k wraps). More generally
for LHS < RHS if RHS-(LHS of first comparison) is a constant then the loop will
iterate either 0 or that constant number of times.
This allows for more loop unrolling with the recent upper bound loop unrolling
changes, and I'm working on a patch that will let loop unrolling additionally
make use of the loop being executed either 0 or k times (we need to retain the
loop comparison only on the first unrolled iteration).
Simon Pilgrim [Tue, 18 Oct 2016 07:42:15 +0000 (07:42 +0000)]
[X86][SSE] Add lowering to cvttpd2dq/cvttps2dq for sitofp v2f64/2f32 to 2i32
As discussed on PR28461 we currently miss the chance to lower "fptosi <2 x double> %arg to <2 x i32>" to cvttpd2dq due to its use of illegal types.
This patch adds support for fptosi to 2i32 from both 2f64 and 2f32.
It also recognises that cvttpd2dq zeroes the upper 64-bits of the xmm result (similar to D23797) - we still don't do this for the cvttpd2dq/cvttps2dq intrinsics - this can be done in a future patch.
[XRay] Support for for tail calls for ARM no-Thumb
This patch adds simplified support for tail calls on ARM with XRay instrumentation.
Known issue: compiled with generic flags: `-O3 -g -fxray-instrument -Wall
-std=c++14 -ffunction-sections -fdata-sections` (this list doesn't include my
specific flags like --target=armv7-linux-gnueabihf etc.), the following program
// Avoid infinite recursion in case the logging function is instrumented (so calls logging
// function again).
[[clang::xray_never_instrument]] void simplyPrint(int32_t functionId, XRayEntryType xret)
{
printf("XRay: functionId=%d type=%d.\n", int(functionId), int(xret));
}
int main(int argc, char* argv[]) {
__xray_set_handler(simplyPrint);
Patching...
XRay: functionId=3 type=0.
In fA()
XRay: functionId=3 type=1.
XRay: functionId=2 type=0.
In fB()
XRay: functionId=2 type=1.
XRay: functionId=1 type=0.
XRay: functionId=1 type=1.
In fC()
Unpatching...
In fA()
In fB()
In fC()
So for function fC() the exit sled seems to be called too much before function
exit: before printing In fC().
Debugging shows that the above happens because printf from fC is also called as
a tail call. So first the exit sled of fC is executed, and only then printf is
jumped into. So it seems we can't do anything about this with the current
approach (i.e. within the simplification described in
https://reviews.llvm.org/D23988 ).
Craig Topper [Tue, 18 Oct 2016 05:44:04 +0000 (05:44 +0000)]
[AVX-512] Add test case to check shuffle decoding for masked vpermilps for r284450.
This is harder to do for vpermilpd as shuffle combining turns the constant vector into an immediate since all vpermilpd's inputs with constant vector can also be encoded with the immediate form.
Justin Bogner [Tue, 18 Oct 2016 05:17:23 +0000 (05:17 +0000)]
Object: Add a missing return in ObjectFile::createObjectFile
When Error was threaded through these APIs back in r265606 the
"return" was missed here, which triggers a warning if/when I add
LLVM_NODISCARD to the Error type.
Andrew Trick [Tue, 18 Oct 2016 04:17:44 +0000 (04:17 +0000)]
Improve tablegen gen-subtarget diagnostics for missing machine models.
-debug-only=subtarget-emitter prints a lot of machine model diagnostics.
This prunes the output so that the "No machine model for XXX on processor YYY"
only appears when there is definitely no machine model for that opcode.
Previously it was printing that error even if the opcode was covered by
a more general scheduling class.
<rdar://problem/15919845> [TableGen][CodeGenSchedule] Debug output does not help spotting the missing scheduling classes
Craig Topper [Tue, 18 Oct 2016 04:00:32 +0000 (04:00 +0000)]
[AVX-512] Fix DecodeVPERMV3Mask to handle cases where the constant pool entry has a different type than the shuffle itself.
Summary: This is especially important for 32-bit targets with 64-bit shuffle elements.This is similar to how PSHUFB and VPERMIL handle the same problem.
Zachary Turner [Mon, 17 Oct 2016 22:49:24 +0000 (22:49 +0000)]
Resubmit "Add support for advanced number formatting."
This resubmits commits 284425 and r284428, which were reverted
in r284429 due to some infinite recursion caused by an incorrect
selection of function overloads. Reproduced the failure on Linux
using GCC 4.8.4, and confirmed that with the new patch the tests
path on GCC as well as MSVC. So hopefully this fixes everything.
Kevin Enderby [Mon, 17 Oct 2016 22:09:25 +0000 (22:09 +0000)]
Next set of additional error checks for invalid Mach-O files for the
load commands that use the MachO::sub_framework_command,
MachO::sub_umbrella_command, MachO::sub_library_command
and MachO::sub_client_command types but are not used in llvm
libObject code but used in llvm tool code.
This includes the LC_SUB_FRAMEWORK, LC_SUB_UMBRELLA,
LC_SUB_LIBRARY and LC_SUB_CLIENT load commands.
Zachary Turner [Mon, 17 Oct 2016 20:57:45 +0000 (20:57 +0000)]
[Support] Add support for "advanced" number formatting.
raw_ostream has not afforded a lot of flexibility in terms of
how to format numbers when outputting. Wrap this all up into
a set of low level helper functions that can be used to output
numbers with arbitrary precision, alignment, format, etc and
then update raw_ostream to use these functions.
This will be useful for upcoming improvements to llvm's string
formatting libraries, but are still useful independently.
Sanjay Patel [Mon, 17 Oct 2016 20:26:46 +0000 (20:26 +0000)]
[DAG] make isConstOrConstSplat and isConstOrConstSplatFP more accessible; NFC
As noted in:
https://reviews.llvm.org/D25685
This is the next-to-smallest step needed to enable the ComputeNumSignBits fix in that patch.
In a minor attempt to keep some structure, we're pulling the FP helper over along with its
integer sibling, but clearly we can and should do more refactoring of the similar helper
functions in DAGCombiner and SelectionDAG to simplify and not duplicate functionality.
Davide Italiano [Mon, 17 Oct 2016 20:05:35 +0000 (20:05 +0000)]
[opt] Strip coverage if debug info is not present.
If -coverage is passed, but -g is not, clang populates the PassManager
pipeline with StripSymbols(debugOnly = true).
The stripSymbol pass therefore scans the list of named metadata,
drops !llvm.dbg.cu, but leaves !llvm.gcov and !0 (the compileUnit MD)
around. The verifier runs, and finds out that there's a CU not listed
in !llvm.dbg.cu (as it was previously dropped) -> crash.
When we strip debug info, so, check if there's coverage data,
and strip it as well, in order to avoid pending metadata left around.
Dehao Chen [Mon, 17 Oct 2016 19:28:44 +0000 (19:28 +0000)]
Ignore debug info when making optimization decisions in SimplifyCFG.
Summary: Debug info should *not* affect code generation. This patch properly handles debug info to make sure the generated code are the same with or without debug info.
Walter Erquinigo [Mon, 17 Oct 2016 18:56:18 +0000 (18:56 +0000)]
Handle relocations to thumb functions when dynamic linking COFF modules
Summary:
This adds the necessary logic to support relocations to thumb functions in the COFF dynamic linker.
The jumps to function addresses are mostly blx, which requires the ISA selection bit when jumping to a thumb function.
Note: I'm determining if the relocation requires the ISA bit when creating the relocation entries and not when resolving the relocation. I have to do that because I need the ObjectFile and the actual Symbol, which are available only when creating the entries. It would require a gross refactor if I do it otherwise, but I'm okay with doing it if you think it's better.
Teresa Johnson [Mon, 17 Oct 2016 14:56:53 +0000 (14:56 +0000)]
Rename interface for querying physical hardware concurrency
Based on post-commit review for D25585/r284180, rename
hardware_physical_concurrency to heavyweight_hardware_concurrency,
to better reflect what type of tasks it should be used for and
to enable other systems to map this to something other than the
number of physical cores.