Matt Arsenault [Wed, 3 Apr 2019 01:58:57 +0000 (01:58 +0000)]
AMDGPU: Assume ECC is enabled by default if supported
The test should really be checking for the property directly in the
code object headers, but there are problems with this. I don't see
this directly represented in the text form, and for the binary
emission this is depending on a function level subtarget feature to
emit a global flag.
[WebAssembly] Add Emscripten OS definition + small_printf
The Emscripten OS provides a definition of __EMSCRIPTEN__, and also that it
supports iprintf optimizations.
Also define small_printf optimizations, which is a printf with float support
but not long double (which in wasm can be useful since long doubles are 128
bit and force linking of float128 emulation code). This part is based on
sunfish's https://reviews.llvm.org/D57620 (which can't land yet since
the WASI integration isn't ready yet).
This change is in preparation for the addition of new target
operand flags for new relocation types. Have a symbol type as part
of the flag set makes it harder to use and AFAICT these are serving
no purpose.
Matt Arsenault [Wed, 3 Apr 2019 00:01:03 +0000 (00:01 +0000)]
AMDGPU: Fix names for generation features
We should overall stop using these, but the uppercase name didn't
work. Any feature string is converted to lowercase, so these
could never be found in the table.
[COFF] Reduce the size of Chunk and SectionChunk, NFC
Summary:
Reorder the fields in both to use padding more efficiently, and add more
comments on the purpose of the fields.
Replace `std::vector<SectionChunk*> AssociativeChildren` with a
singly-linked list. This avoids the separate vector allocation to list
associative children, and shrinks the 3 pointers used for the typically
empty vector down to 1.
In the end, this reduces the sum of heap allocations used to link
browser_tests.exe with NO PDB by 13.10%, going from 2,248,728 KB to
1,954,071 KB of heap. These numbers exclude memory mapped files, which
are of course a significant factor in LLD's memory usage.
[X86] Mark the default case of the X86InstrInfo::convertToThreeAddress switch as unreachable.
This function should only be called with instructions that are really convertible. And all
convertible instructions need to be handled by the switch. So nothing should use the default.
[X86] Check MI.isConvertibleTo3Addr() before calling convertToThreeAddress in X86FixupLEAs.
X86FixupLEAs just assumes convertToThreeAddress will return nullptr for any instruction that isn't convertible.
But the code in convertToThreeAddress for X86 assumes that any instruction coming in has at least 2 operands and that the second one is a register. But those properties aren't guaranteed of all instructions. We should check the instruction property first.
[TableGen] Properly calculate the minimum size needed or ConvertFn in GenAsmmatcher.inc files
We were using the number of Matchables rather than the number of rows in the converter table.
This only matters for a few of the targets where the number of matchables is more than 255, but the number of converters is less than 255. Many of the targets have more than 256 converters. So already required a uint16_t.
This adds partial instruction selection support for llvm.aarch64.stlxr. It also
factors out selection for G_INTRINSIC_W_SIDE_EFFECTS into its own function. The
new function removes the restriction that the intrinsic ID on the
G_INTRINSIC_W_SIDE_EFFECTS be on operand 0.
Also add a test, and add a GISel line to arm64-ldxr-stxr.ll.
In the bug test case the debug location was missing for the cmp instruction in
the "middle block" BB. This patch fixes the bug by copying the debug location
from the cmp of the scalar loop's terminator branch, if it exists.
The patch also fixes the debug location on the subsequent branch instruction.
It was previously using the location of the of the original loop's pre-header
block terminator. Both of these instructions will now map to the source line of
the conditional branch in the original loop.
A regression test has been added that covers these issues.
Stefan Pintilie [Tue, 2 Apr 2019 16:56:01 +0000 (16:56 +0000)]
[PowerPC] Fix reversed bit issue in DCMX mask for "xvtstdcdp" and "xvtstdcsp" P9 implementation
Did experiments on power 9 machine, checked the outputs for NaN & Infinity+
cases with corresponding DCMX bit set. Confirmed the DCMX mask bit for NaN and
infinity+ are reversed.
Philip Reames [Tue, 2 Apr 2019 16:51:43 +0000 (16:51 +0000)]
[WideableCond] Fix a nasty bug in detection of "explicit guards"
The code was failing to actually check for the presence of the call to widenable_condition. The whole point of specifying the widenable_condition intrinsic was allowing widening transforms. A normal branch is not widenable. A normal branch leading to a deopt is not widenable (in general).
I added a test case via LoopPredication, but GuardWidening has an analogous bug. Those are the only two passes actually using this utility just yet. Noticed while working on LoopPredication for non-widenable branches; POC in D60111.
[llvm-objcopy] Change SHT_NOBITS to SHT_PROBITS for some --set-section-flags
Summary:
Some flags accepted by --set-section-flags and --rename-section can change a SHT_NOBITS section to a SHT_PROGBITS section. Note that none of them can change a SHT_PROGBITS to SHT_NOBITS.
The full list (found via experimentation of individually setting each flag) that does this is: contents, load, noload, code, data, rom, and debug.
This was found by testing llvm-objcopy with the gnu binutils test suite, specifically this test case: https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob;f=binutils/testsuite/binutils-all/copy-1.d;h=f2b0d9e90df738c2891b4d5c7b62f62894b556ca;hb=HEAD
When we're cross-compiling, build and use a native llvm-nm instead of
attempting to use the one from the target's build tree.
A nice follow-up would be to add a cache variable to allow specifying a
path to an external native llvm-nm instead of building one ourselves,
similar to LLVM_TABLEGEN and LLVM_CONFIG_PATH.
Instead of duplicating functionality for building native versions of
tblgen and llvm-config, add a function to set up a native tool build.
This will also be used for llvm-nm in a follow-up.
This should be NFC for tblgen, besides the slightly different COMMENT
for the custom command (it'll display the tablegen target name instead
of always saying TableGen). For the native llvm-config, it's a behavior
change in that we'll use llvm_ExternalProject_BuildCmd instead of
constructing the build command manually, always build in Release, and
reference the correct binary path for multi-config generators. I believe
all of these changes to be bug fixes.
Summary:
When inserting an `unreachable` after a noreturn call, we must ensure
that it's not a musttail call to avoid breaking the IR invariants for
musttail calls.
[SampleProfile] Repeat indirect call promotion only when the target is actually hot.
Summary: It is possible that multiple indirect call targets have been promoted for a single callsite from the profiled binary. Current implementation repeats promotion for all these targets as far as the callsite itself is hot (the callsite is assumed to be hot if any one of these targets was "hot" during the profiling). However, even when one of the ICPed target is hot other targets may not, and we should not repeat promotion for "cold" targets.
Summary:
When inserting an `unreachable` after a noreturn call, we must ensure
that it's not a musttail call to avoid breaking the IR invariants for
musttail calls.
Jonas Paulsson [Tue, 2 Apr 2019 15:36:30 +0000 (15:36 +0000)]
[SystemZ] Improve instruction selection of 64 bit shifts and rotates.
For shift and rotate instructions that only use the last 6 bits of the shift
amount, a shift amount of (x*64-s) can be substituted with (-s). This saves
one instruction and a register:
Brian Gesiak [Tue, 2 Apr 2019 14:57:56 +0000 (14:57 +0000)]
[Transforms] Redundant getValueOperand (NFC)
`StoreInst::getValueOperand` is identical to `getOperand(0)`, so the call to
`getOperand(0)` can be replaced. Further, `SI->getValueOperand` is redundantly
called just a few lines down, despite its return value being stored in variable
`DV`. No functional change.
James Henderson [Tue, 2 Apr 2019 14:11:13 +0000 (14:11 +0000)]
[llvm-objcopy]Allow llvm-objcopy to be used on an ELF file with no section headers
This patch fixes https://bugs.llvm.org/show_bug.cgi?id=41293 and
https://bugs.llvm.org/show_bug.cgi?id=41045. llvm-objcopy assumed that
it could always read a section header string table. This isn't the case
when the sections were previously all stripped, and the e_shstrndx field
was set to 0. This patch fixes this. It also fixes a double space in an
error message relating to this issue, and prevents llvm-objcopy from
adding extra space for non-existent section headers, meaning that
--strip-sections on the output of a previous --strip-sections run
produces identical output, simplifying the test.
Simon Atanasyan [Tue, 2 Apr 2019 13:57:32 +0000 (13:57 +0000)]
[mips] Use AltOrders to prevent using odd FP-registers
To disable using of odd floating-point registers (O32 ABI and
-mno-odd-spreg command line option) such registers and their
super-registers added to the set of reserved registers. In general, it
works. But there is at least one problem - in case of enabled machine
verifier pass some floating-point tests failed because live ranges of
register units that are reserved is not empty and verification pass
failed with "Live segment doesn't end at a valid instruction" error
message.
There is D35985 patch which tries to solve the problem by explicit
removing of register units. This solution did not get approval.
I would like to use another approach for prevent using odd floating
point registers - define `AltOrders` and `AltOrderSelect` for MIPS
floating point register classes. Such `AltOrders` contains reduced set
of registers. At first glance, such solution does not break any test
cases and allows enabling machine instruction verification for all MIPS
test cases.
Pavel Labath [Tue, 2 Apr 2019 11:58:37 +0000 (11:58 +0000)]
Add minidump support to obj2yaml
Summary:
This patch adds the code needed to parse a minidump file into the
MinidumpYAML model, and the necessary glue code so that obj2yaml can
recognise the minidump files and process them.
There are various places in LLVM where the definition of StackID is not
properly honoured, for example in PEI where objects with a StackID > 0 are
allocated on the default stack (StackID0). This patch enforces that PEI
only considers allocating objects to StackID 0.
Hans Wennborg [Tue, 2 Apr 2019 08:01:38 +0000 (08:01 +0000)]
SimplifyCFG SinkCommonCodeFromPredecessors: Also sink function calls without used results (PR41259)
The code was previously checking that candidates for sinking had exactly
one use or were a store instruction (which can't have uses). This meant
we could sink call instructions only if they had a use.
That limitation seemed a bit arbitrary, so this patch changes it to
"instruction has zero or one use" which seems more natural and removes
the need to special-case stores.
The code doesn't actually need any of the information about the widenable condition at this level. The only thing we need is to ensure the WC call is the last thing anded in, and even that is a quirk we should really look to remove.
Eli Friedman [Tue, 2 Apr 2019 00:01:23 +0000 (00:01 +0000)]
[ARM] Optimize expressions like "return x != 0;" for Thumb1.
There's an existing optimization for x != C, but somehow it was missing
a special case for 0.
While I'm here, also cleaned up the code/comments a bit: the second
value produced by the MERGE_VALUES was actually dead, since a CMOV only
produces one result.
Eli Friedman [Mon, 1 Apr 2019 23:55:57 +0000 (23:55 +0000)]
[ARM] Don't try to create "push {r12, lr}" in Thumb1 at -Oz.
It's a little tricky to make this issue show up because
prologue/epilogue emission normally likes to push at least two
registers... but it doesn't when lr is force-spilled due to function
length. Not sure if that really makes sense, but I decided not to touch
it for now.
[X86] Classify the AVX512 rounding control operand as X86::OPERAND_ROUNDING_CONTROL instead of MCOI::OPERAND_IMMEDIATE. Add an assert on legal values of rounding control in the encoder and remove an explicit mask.
This should allow llvm-exegesis to intelligently constrain the rounding mode.
The mask in the encoder shouldn't be necessary any more. We used to allow codegen to use 8-11 for rounding mode and the assembler would use 0-3 to mean the same thing so we masked here and in the printer. Codegen now matches the assembler and the printer was updated, but I forgot to update the encoder.
Philip Reames [Mon, 1 Apr 2019 16:26:08 +0000 (16:26 +0000)]
[LoopPred] Be uniform about proving generated conditions
We'd been optimizing the case where the predicate was obviously true, do the same for the false case. Mostly just for completeness sake, but also may improve compile time in loops which will exit through the guard. Such loops are presumed rare in fastpath code, but may be present down untaken paths, so optimizing for them is still useful.
Summary:
Previously, we translate llvm.round to PTX cvt.rni, which rounds to the
even interger when the source is equidistant between two integers. This
is not correct as llvm.round should round away from zero. This change
replaces llvm.round with a round away from zero implementation through
target specific custom lowering.
Modify a few affected tests to not check for cvt.rni. Instead, we check
for the use of a few constants used in implementing round. We are also
adding CUDA runnable tests to check for the values produced by
llvm.round to test-suites/External/CUDA.
Philip Reames [Mon, 1 Apr 2019 16:05:15 +0000 (16:05 +0000)]
[LoopPred] Delete the old condition expressions if unused
LoopPredication was replacing the original condition, but leaving the instructions to compute the old conditions around. This would get cleaned up by other passes of course, but we might as well do it eagerly. That also makes the test output less confusing.
Philip Reames [Mon, 1 Apr 2019 15:32:07 +0000 (15:32 +0000)]
[Tests] Add tests for a possible loop predication transform variant
As highlighted by tests, if one of the operands is loop variant, but guaranteed to have the same value on all iterations, we have a missed oppurtunity.
Neil Henning [Mon, 1 Apr 2019 15:19:52 +0000 (15:19 +0000)]
[AMDGPU] Pre-allocate WWM registers to reduce VGPR pressure.
This change incorporates an effort by Connor Abbot to change how we deal
with WWM operations potentially trashing valid values in inactive lanes.
Previously, the SIFixWWMLiveness pass would work out which registers
were being trashed within WWM regions, and ensure that the register
allocator did not have any values it was depending on resident in those
registers if the WWM section would trash them. This worked perfectly
well, but would cause sometimes severe register pressure when the WWM
section resided before divergent control flow (or at least that is where
I mostly observed it).
This fix instead runs through the WWM sections and pre allocates some
registers for WWM. It then reserves these registers so that the register
allocator cannot use them. This results in a significant register
saving on some WWM shaders I'm working with (130 -> 104 VGPRs, with just
this change!).
Alex Bradbury [Mon, 1 Apr 2019 14:53:17 +0000 (14:53 +0000)]
[RISCV] Attach VK_RISCV_CALL to symbols upon creation
This patch replaces the addition of VK_RISCV_CALL in RISCVMCCodeEmitter by
creating the RISCVMCExpr when tail/call are parsed, or in the codegen case
when the callee symbols are created.
This required adding a new CallSymbol operand to allow only adding
VK_RISCV_CALL to tail/call instructions.
This patch will allow further expansion of parsing and codegen to easily
include PLT symbols which must generate the R_RISCV_CALL_PLT relocation.
Differential Revision: https://reviews.llvm.org/D55560
Patch by Lewis Revill.
The STGV/LDGV instructions were replaced with
STGM/LDGM. The encodings remain the same but there
is no longer writeback so there are no unpredictable
encodings to check for.
The specfication can be found here:
https://developer.arm.com/docs/ddi0596/c
Alex Bradbury [Mon, 1 Apr 2019 14:42:56 +0000 (14:42 +0000)]
[RISCV] Generate address sequences suitable for mcmodel=medium
This patch adds an implementation of a PC-relative addressing sequence to be
used when -mcmodel=medium is specified. With absolute addressing, a 'medium'
codemodel may cause addresses to be out of range. This is because while
'medium' implies a 2 GiB addressing range, this 2 GiB can be at any offset as
opposed to 'small', which implies the first 2 GiB only.
Note that LLVM/Clang currently specifies code models differently to GCC, where
small and medium imply the same functionality as GCC's medlow and medany
respectively.
Differential Revision: https://reviews.llvm.org/D54143
Patch by Lewis Revill.
The latest version of the MTE spec added a system
register 'GMID_EL1'. It contains the block size used
by the LDGM and STGM instructions and is read only.
The specification can be found here:
https://developer.arm.com/docs/ddi0596/c
Mikael Holmen [Mon, 1 Apr 2019 14:10:10 +0000 (14:10 +0000)]
[InstCombine] Handle vector gep with scalar argument in evaluateInDifferentElementOrder
Summary:
This fixes PR41270.
The recursive function evaluateInDifferentElementOrder expects to be called
on a vector Value, so when we call it on a vector GEP's arguments, we must
first check that the argument is indeed a vector.
Mikael Holmen [Mon, 1 Apr 2019 13:48:56 +0000 (13:48 +0000)]
[InstCombine] Handle vector gep with scalar argument in evaluateInDifferentElementOrder
This fixes PR41270.
The recursive function evaluateInDifferentElementOrder expects to be called
on a vector Value, so when we call it on a vector GEP's arguments, we must
first check that the argument is indeed a vector.
PR41304:
https://bugs.llvm.org/show_bug.cgi?id=41304
...is currently titled as an SLP enhancement, but at least for the
given example, we can reduce that in instcombine because we are just
eliminating shuffles.
As noted in the TODO, this could be generalized, but I haven't thought
through those patterns completely, so this is limited to what appears
to be always safe.