- Disable incremental linking by default. /INCREMENTAL adds extra thunks in the EXE, which makes execution slower.
- Set /MT (static CRT lib) by default instead of CMake's default /MD (dll CRT lib). The previous default /MD makes all DLL functions to be thunked, thus making execution slower (memcmp, memset, etc.)
- Adds LLVM_ENABLE_INCREMENTAL_LINK which is set to OFF by default.
Differential revision: https://reviews.llvm.org/D55056
llvm-svn: 349517
Summary: This the initial code change to facilitate managing FMF flags from Instructions to MI wrt Intrinsics in Global Isel. Eventually the GlobalObserver interface will be added as well, where FMF additions can be tracked for the builder and CSE.
Reviewers: aditya_nandakumar, bogner
Reviewed By: bogner
Subscribers: rovka, kristof.beyls, javed.absar
Differential Revision: https://reviews.llvm.org/D55668
llvm-svn: 349514
Rename:
NoUnrolling to InterleaveOnlyWhenForced
and
AlwaysVectorize to !VectorizeOnlyWhenForced
Contrary to what the name 'AlwaysVectorize' suggests, it does not
unconditionally vectorize all loops, but applies a cost model to
determine whether vectorization is profitable to all loops. Hence,
passing false will disable the cost model, except when a loop is marked
with llvm.loop.vectorize.enable. The 'OnlyWhenForced' suffix (suggested
by @hfinkel in D55716) better matches this behavior.
Similarly, 'NoUnrolling' disables the profitability cost model for
interleaving (a term to distinguish it from unrolling by the
LoopUnrollPass); rename it for consistency.
Differential Revision: https://reviews.llvm.org/D55785
llvm-svn: 349513
When using clang with `-fno-unroll-loops` (implicitly added with `-O1`),
the LoopUnrollPass is not not added to the (legacy) pass pipeline. This
also means that it will not process any loop metadata such as
llvm.loop.unroll.enable (which is generated by #pragma unroll or
WarnMissedTransformationsPass emits a warning that a forced
transformation has not been applied (see
https://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20181210/610833.html).
Such explicit transformations should take precedence over disabling
heuristics.
This patch unconditionally adds LoopUnrollPass to the optimizing
pipeline (that is, it is still not added with `-O0`), but passes a flag
indicating whether automatic unrolling is dis-/enabled. This is the same
approach as LoopVectorize uses.
The new pass manager's pipeline builder has no option to disable
unrolling, hence the problem does not apply.
Differential Revision: https://reviews.llvm.org/D55716
llvm-svn: 349509
Add support for s64 libcalls for G_SDIV, G_UDIV, G_SREM and G_UREM
and use integer type of correct size when creating arguments for
CLI.lowerCall.
Select G_SDIV, G_UDIV, G_SREM and G_UREM for types s8, s16, s32 and s64
on MIPS32.
Differential Revision: https://reviews.llvm.org/D55651
llvm-svn: 349499
Also add build files for deps DebugInfo/Symbolize, ToolDrivers/dll-tool.
Also add gn/build/libs/xar (needed by llvm-objdump).
Also delete an incorrect part of the symlink description in //BUILD.gn (it used
to be true before I made the symlink step write a stamp file; now it's no
longer true).
These are all binaries needed by check-lld that need symlinks.
Differential Revision: https://reviews.llvm.org/D55743
llvm-svn: 349486
Replace the X86ISD opcodes ADDUS and SUBUS with generic ISD opcodes
UADDSAT and USUBSAT. As a side-effect, this also makes codegen for
the @llvm.uadd.sat and @llvm.usub.sat intrinsics reasonable.
This only replaces use in the X86 backend, and does not move any of
the ADDUS/SUBUS X86 specific combines into generic codegen.
Differential Revision: https://reviews.llvm.org/D55787
llvm-svn: 349481
Some recent experience on llvm-dev pointed out some errors in the document:
- Assumption of ninja
- Use of --march rather than -march
- Problems with host include files when a multiarch setup was used
- Insufficient target information passed to assembler
- Instructions on using the cmake cache file BaremetalARM.cmake were
incomplete
There was also insufficient guidance on what to do when various stages
failed due to misconfiguration or missing steps.
Summary of changes:
- Fixed problems above
- Added a troubleshooting section with common errors.
- Cleared up one "at time of writing" that is no longer a problem.
Differential Revision: https://reviews.llvm.org/D55709
llvm-svn: 349477
This is https://bugs.llvm.org/show_bug.cgi?id=39992,
If we have the following code (test.cpp):
thread_local int tdata = 24;
and build an .o file with debug information:
clang --target=x86_64-pc-linux -c bar.cpp -g
Then object produced may have R_X86_64_DTPOFF64/R_X86_64_DTPOFF32 relocations.
(clang emits R_X86_64_DTPOFF64 and gcc emits R_X86_64_DTPOFF32 for the code above for me)
Currently, llvm-dwarfdump fails to compute this TLS relocation when dumping
object and reports an
error:
failed to compute relocation: R_X86_64_DTPOFF64, Invalid data was encountered while parsing the file
This relocation represents the offset in the TLS block and resolved by the linker,
but this info is unavailable at the
point when the object file is dumped by this tool.
The patch adds the simple evaluation for such relocations to avoid emitting errors.
Resulting behavior seems to be equal to GNU dwarfdump.
Differential revision: https://reviews.llvm.org/D55762
llvm-svn: 349476
Add narrowScalar for G_AND and G_XOR.
Legalize G_AND G_OR and G_XOR for types other then s32
with clampScalar on MIPS32.
Differential Revision: https://reviews.llvm.org/D55362
llvm-svn: 349475
- Reapply changes intially introduced in r343089
- The archtecture info is no longer loaded whenever a DWARFContext is created
- The runtimes libraries (santiziers) make use of the dwarf context classes but
do not intialise the target info
- The architecture of the object can be obtained without loading the target info
- Adding a method to the dwarf context to get this information and multiplex the
string printing later on
Differential Revision: https://reviews.llvm.org/D55774
llvm-svn: 349472
This modifies the IPO pass so that it respects any explicit function
address space specified in the data layout.
In targets with nonzero program address spaces, all functions should, by
default, be placed into the default program address space.
This is required for Harvard architectures like AVR. Without this, the
functions will be marked as residing in data space, and thus not be
callable.
This has no effect to any in-tree official backends, as none use an
explicit program address space in their data layouts.
Patch by Tim Neumann.
llvm-svn: 349469
For opcodes not covered by SimplifyDemandedVectorElts, SimplifyDemandedBits might be able to help now that it supports demanded elts as well.
llvm-svn: 349466
When splitting up an alloca's uses we were dropping any explicit
alignment tags, which means they default to the ABI-required default
alignment and this can cause miscompiles if the real value was smaller.
Also refactor the TBAA metadata into a parent class since it's shared by
both children anyway.
llvm-svn: 349465
(VSRAI (VSHLI X, C1), C1) --> X iff NumSignBits(X) > C1
This works better as part of SimplifyDemandedBits than part of the general combine.
llvm-svn: 349462
This fold was incredibly specific - replace with a SimplifyDemandedBits fold to remove a VSRAI if only the original sign bit is demanded (its guaranteed to stay the same).
Test change is merely a rescheduling.
llvm-svn: 349459
The pass implements tracking of control flow miss-speculation into a "taint"
register. That taint register can then be used to mask off registers with
sensitive data when executing under miss-speculation, a.k.a. "transient
execution".
This pass is aimed at mitigating against SpectreV1-style vulnarabilities.
At the moment, it implements the tracking of miss-speculation of control
flow into a taint register, but doesn't implement a mechanism yet to then
use that taint register to mask off vulnerable data in registers (something
for a follow-on improvement). Possible strategies to mask out vulnerable
data that can be implemented on top of this are:
- speculative load hardening to automatically mask of data loaded
in registers.
- using intrinsics to mask of data in registers as indicated by the
programmer (see https://lwn.net/Articles/759423/).
For AArch64, the following implementation choices are made.
Some of these are different than the implementation choices made in
the similar pass implemented in X86SpeculativeLoadHardening.cpp, as
the instruction set characteristics result in different trade-offs.
- The speculation hardening is done after register allocation. With a
relative abundance of registers, one register is reserved (X16) to be
the taint register. X16 is expected to not clash with other register
reservation mechanisms with very high probability because:
. The AArch64 ABI doesn't guarantee X16 to be retained across any call.
. The only way to request X16 to be used as a programmer is through
inline assembly. In the rare case a function explicitly demands to
use X16/W16, this pass falls back to hardening against speculation
by inserting a DSB SYS/ISB barrier pair which will prevent control
flow speculation.
- It is easy to insert mask operations at this late stage as we have
mask operations available that don't set flags.
- The taint variable contains all-ones when no miss-speculation is detected,
and contains all-zeros when miss-speculation is detected. Therefore, when
masking, an AND instruction (which only changes the register to be masked,
no other side effects) can easily be inserted anywhere that's needed.
- The tracking of miss-speculation is done by using a data-flow conditional
select instruction (CSEL) to evaluate the flags that were also used to
make conditional branch direction decisions. Speculation of the CSEL
instruction can be limited with a CSDB instruction - so the combination of
CSEL + a later CSDB gives the guarantee that the flags as used in the CSEL
aren't speculated. When conditional branch direction gets miss-speculated,
the semantics of the inserted CSEL instruction is such that the taint
register will contain all zero bits.
One key requirement for this to work is that the conditional branch is
followed by an execution of the CSEL instruction, where the CSEL
instruction needs to use the same flags status as the conditional branch.
This means that the conditional branches must not be implemented as one
of the AArch64 conditional branches that do not use the flags as input
(CB(N)Z and TB(N)Z). This is implemented by ensuring in the instruction
selectors to not produce these instructions when speculation hardening
is enabled. This pass will assert if it does encounter such an instruction.
- On function call boundaries, the miss-speculation state is transferred from
the taint register X16 to be encoded in the SP register as value 0.
Future extensions/improvements could be:
- Implement this functionality using full speculation barriers, akin to the
x86-slh-lfence option. This may be more useful for the intrinsics-based
approach than for the SLH approach to masking.
Note that this pass already inserts the full speculation barriers if the
function for some niche reason makes use of X16/W16.
- no indirect branch misprediction gets protected/instrumented; but this
could be done for some indirect branches, such as switch jump tables.
Differential Revision: https://reviews.llvm.org/D54896
llvm-svn: 349456
The default still is dwarf, but SEH exceptions can now be enabled
optionally for the MinGW target.
Differential Revision: https://reviews.llvm.org/D55748
llvm-svn: 349451
Power9 VABSDU* instructions can be exploited for some special vselect sequences.
Check in the orignal test case here, later the exploitation patch will update this
and reviewers can check the differences easily.
llvm-svn: 349446
This is a follow up for rL347910. In the original patch I somehow forgot to pass
the limit from wrappers to the function which actually does the job.
llvm-svn: 349438
Improve the current vec_abs support on P9, generate ISD::ABS node for vector types,
combine ABS node to VABSD node for some special cases to make use of P9 VABSD* insns,
do custom lowering to vsub(vneg later)+vmax if it has no combination opportunity.
Differential Revision: https://reviews.llvm.org/D54783
llvm-svn: 349437
In PDBs, symbol records must be aligned to four bytes. However, in the
object file, symbol records may not be aligned. MSVC does not pad out
symbol records to make sure they are aligned. That means the linker has
to do extra work to insert the padding. Currently, LLD calculates the
required space with alignment, and copies each record one at a time
while padding them out to the correct size. It has a fast path that
avoids this copy when the records are already aligned.
This change fixes a bug in that codepath so that the copy is actually
saved, and tweaks LLVM's symbol record emission to align symbol records.
Here's how things compare when doing a plain clang Release+PDB build:
- objs are 0.65% bigger (negligible)
- link is 3.3% faster (negligible)
- saves allocating 441MB
- new LLD high water mark is ~1.05GB
llvm-svn: 349431
Mucking about simplifying a test case ( https://reviews.llvm.org/D55261 ) I stumbled across something I've hit before - that LLVM's (GCC's does too, FWIW) assembly output includes a hardcode length for a DWARF unit in its header. Instead we could emit a label difference - making the assembly easier to read/edit (though potentially at a slight (I haven't tried to observe it) performance cost of delaying/sinking the length computation into the MC layer).
Fix: Predicated all the changes (including creating the labels, even if they aren't used/needed) behind the NVPTX useSectionsAsReferences, avoiding emitting labels in NVPTX where ptxas can't parse them.
Reviewers: JDevlieghere, probinson, ABataev
Differential Revision: https://reviews.llvm.org/D55281
llvm-svn: 349430
Apply final suggestions from probinson for this patch series plus a
few more tweaks:
* Improve various docs, for MatchType in particular.
* Rename some members of MatchType. The main problem was that the
term "final match" became a misnomer when CHECK-COUNT-<N> was
created.
* Split InputStartLine, etc. declarations into multiple lines.
Differential Revision: https://reviews.llvm.org/D55738
Reviewed By: probinson
llvm-svn: 349425
This patch implements annotations for diagnostics reporting CHECK-NOT
failed matches. These diagnostics are enabled by -vv. As for
diagnostics reporting failed matches for other directives, these
annotations mark the search ranges using `X~~`. The difference here
is that failed matches for CHECK-NOT are successes not errors, so they
are green not red when colors are enabled.
For example:
```
$ FileCheck -dump-input=help
The following description was requested by -dump-input=help to
explain the input annotations printed by -dump-input=always and
-dump-input=fail:
- L: labels line number L of the input file
- T:L labels the only match result for a pattern of type T from line L of
the check file
- T:L'N labels the Nth match result for a pattern of type T from line L of
the check file
- ^~~ marks good match (reported if -v)
- !~~ marks bad match, such as:
- CHECK-NEXT on same line as previous match (error)
- CHECK-NOT found (error)
- CHECK-DAG overlapping match (discarded, reported if -vv)
- X~~ marks search range when no match is found, such as:
- CHECK-NEXT not found (error)
- CHECK-NOT not found (success, reported if -vv)
- CHECK-DAG not found after discarded matches (error)
- ? marks fuzzy match when no match is found
- colors success, error, fuzzy match, discarded match, unmatched input
If you are not seeing color above or in input dumps, try: -color
$ FileCheck -vv -dump-input=always check5 < input5 |& sed -n '/^<<<</,$p'
<<<<<<
1: abcdef
check:1 ^~~
not:2 X~~
2: ghijkl
not:2 ~~~
check:3 ^~~
3: mnopqr
not:4 X~~~~~
4: stuvwx
not:4 ~~~~~~
5:
eof:4 ^
>>>>>>
$ cat check5
CHECK: abc
CHECK-NOT: foobar
CHECK: jkl
CHECK-NOT: foobar
$ cat input5
abcdef
ghijkl
mnopqr
stuvwx
```
Reviewed By: george.karpenkov, probinson
Differential Revision: https://reviews.llvm.org/D53899
llvm-svn: 349424
This patch implements input annotations for diagnostics reporting
CHECK-DAG discarded matches. These diagnostics are enabled by -vv.
These annotations mark discarded match ranges using `!~~` because they
are bad matches even though they are not errors.
CHECK-DAG discarded matches create another case where there can be
multiple match results for the same directive.
For example:
```
$ FileCheck -dump-input=help
The following description was requested by -dump-input=help to
explain the input annotations printed by -dump-input=always and
-dump-input=fail:
- L: labels line number L of the input file
- T:L labels the only match result for a pattern of type T from line L of
the check file
- T:L'N labels the Nth match result for a pattern of type T from line L of
the check file
- ^~~ marks good match (reported if -v)
- !~~ marks bad match, such as:
- CHECK-NEXT on same line as previous match (error)
- CHECK-NOT found (error)
- CHECK-DAG overlapping match (discarded, reported if -vv)
- X~~ marks search range when no match is found, such as:
- CHECK-NEXT not found (error)
- CHECK-DAG not found after discarded matches (error)
- ? marks fuzzy match when no match is found
- colors success, error, fuzzy match, discarded match, unmatched input
If you are not seeing color above or in input dumps, try: -color
$ FileCheck -vv -dump-input=always check4 < input4 |& sed -n '/^<<<</,$p'
<<<<<<
1: abcdef
dag:1 ^~~~
dag:2'0 !~~~ discard: overlaps earlier match
2: cdefgh
dag:2'1 ^~~~
check:3 X~ error: no match found
>>>>>>
$ cat check4
CHECK-DAG: abcd
CHECK-DAG: cdef
CHECK: efgh
$ cat input4
abcdef
cdefgh
```
This shows that the line 3 CHECK fails to match even though its
pattern appears in the input because its search range starts after the
line 2 CHECK-DAG's match range. The trouble might be that the line 2
CHECK-DAG's match range is later than expected because its first match
range overlaps with the line 1 CHECK-DAG match range and thus is
discarded.
Because `!~~` for CHECK-DAG does not indicate an error, it is not
colored red. Instead, when colors are enabled, it is colored cyan,
which suggests a match that went cold.
Reviewed By: george.karpenkov, probinson
Differential Revision: https://reviews.llvm.org/D53898
llvm-svn: 349423