A common idiom in some code is to do the following:
memset(dst, 0, dst_size);
memcpy(dst, src, src_size);
Some of the memset is redundant; instead, we can do:
memcpy(dst, src, src_size);
memset(dst + src_size, 0,
dst_size <= src_size ? 0 : dst_size - src_size);
Original patch by: Joel Jones
Differential Revision: http://reviews.llvm.org/D498
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235232 91177308-0d34-0410-b5e6-96231b3b80d8
Similar to r235222, but for the weak symbol case.
In an "ideal" assembler/object format an expression would always refer to the
final value and A-B would only be computed from a section in the same
comdat as A and B with A and B strong.
Unfortunately that is not the case with debug info on ELF, so we need an
heuristic. Since we need an heuristic, we may as well use the same one as
gas:
* call weak_sym : produces a relocation, even if in the same section.
* A - weak_sym and weak_sym -A: don't produce a relocation if we can
compute it.
This fixes pr23272 and changes the fix of pr22815 to match what gas does.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235227 91177308-0d34-0410-b5e6-96231b3b80d8
They would break the SelectionDAG.
Note that the opposite load->vector dependency is already obvious in:
(LD1*post vec, ..)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235224 91177308-0d34-0410-b5e6-96231b3b80d8
Part of pr23272.
A small annoyance with the assembly syntax we implement is that given an
expression there is no way to know if what is desired is the value of that
expression for the symbols in this file or for the final values of those
symbols in a link.
The first case is useful for use in sections that get discarded or ignored
if the section they are describing is discarded.
For axample, consider A-B where A and B are in the same comdat section.
We can compute the value of the difference in the section that is present in
the current .o and if that section survives to the final DSO the value will
still will be correct.
But the section is in a comdat. Another section from another object file
might be used istead. We know that that section will define A and B, but
we have no idea what the value of A-B might be.
In practice we have to assume that the intention is to compute the value
in the current section since otherwise the is no way to create something like
the debug aranges section.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235222 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This patch adds legalization support to operate on FP16 as a load/store type
and do operations on it as floats.
Tests for ARM are added to test/CodeGen/ARM/fp16-promote.ll
Reviewers: srhines, t.p.northover
Differential Revision: http://reviews.llvm.org/D8755
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235215 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Implement the method FastMaterializeAlloca in Mips fast-isel
Based on a patch by Reed Kotler.
Test Plan:
Passes test-suite at O0/O2 for mips32 r1/r2
fastalloca.ll
Reviewers: dsanders, rkotler
Subscribers: rfuhler, llvm-commits
Differential Revision: http://reviews.llvm.org/D6742
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235213 91177308-0d34-0410-b5e6-96231b3b80d8
The v1i128 type is needed for the quadword add/substract instructions introduced
in POWER8. Futhermore, the PowerPC ABI specifies that parameters of type v1i128
are to be passed in a single vector register, while parameters of type i128 are
passed in pairs of GPRs. Thus, it is necessary to be able to differentiate
between v1i128 and i128 in LLVM.
http://reviews.llvm.org/D8564
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235198 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Add shift operators implementation to fast-isel for Mips. These are shift ops
for non legal forms, i.e. i8 and i16.
Based on a patch by Reed Kotler.
Test Plan:
Reviewers: dsanders
Subscribers: echristo, rfuhler, llvm-commits
Differential Revision: http://reviews.llvm.org/D6726
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235194 91177308-0d34-0410-b5e6-96231b3b80d8
This is a followon to r233681 - I'd misunderstood the semantics of FTRUNC,
and had confused it with (FP_ROUND ..., 0).
Thanks for Ahmed Bougacha for his post-commit review!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235191 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Previously, the presence of KILL instructions would block valid candidates
from filling a specific delay slot. With the elimination of the KILL
instructions, in the appropriate range, we are able to fill more slots and
keep the information from future def/use analysis consistent.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: hfinkel, llvm-commits
Differential Revision: http://reviews.llvm.org/D7724
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235183 91177308-0d34-0410-b5e6-96231b3b80d8
Linkers normally read all the relocations upfront to compute the references
between sections. Putting them together is a bit more cache friendly.
I benchmarked linking a Release+Asserts clang with gold on a vm. I tried all
4 combinations of --gc-sections/no --gc-section hot and cold cache.
I cleared the cache with
echo 3 > /proc/sys/vm/drop_caches
and warmed it up by running the link once before timing the subsequent ones.
With cold cache and --gc-sections the time goes from
1.86130781665 +- 0.01713126697463843 seconds
to
1.82370735105 +- 0.014127522318814516 seconds
With cold cache and no --gc-sections the time goes from
1.6087245435500002 +- 0.012999066825178644 seconds
to
1.5687122041500001 +- 0.013145850126026619 seconds
With hot cache and no --gc-sections the time goes from
0.926200939 ( +- 0.33% ) seconds
to
0.907200079 ( +- 0.31% ) seconds
With hot cache and gc sections the time goes from
1.183038049 ( +- 0.34% ) seconds
to
1.147355862 ( +- 0.39% ) seconds
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235165 91177308-0d34-0410-b5e6-96231b3b80d8
Use an extra bit in the CCInfo to flag the newer version of the
instructiont hat includes the type explicitly.
Tested the newer error cases I added, but didn't add tests for the finer
granularity improvements to existing error paths.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235160 91177308-0d34-0410-b5e6-96231b3b80d8
This now emits simple, unoptimized xdata tables for __C_specific_handler
based on the handlers listed in @llvm.eh.actions calls produced by
WinEHPrepare.
This adds support for running __finally blocks when exceptions are
thrown, and removes the old landingpad fan-in codepath.
I ran some manual execution tests on small basic test cases with and
without optimization, as well as on Chrome base_unittests, which uses a
small amount of SEH. I'm sure there are bugs, and we may need to
revert.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235154 91177308-0d34-0410-b5e6-96231b3b80d8
This shouldn't have used varargs anyway; change the functions to be
`void`. Also remove my accidentally-committed directory path.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235152 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
An alternative is to use a worklist approach. However, that approach
would break the traversing order so that we couldn't lookup SeenExprs
efficiently. I don't see a clear winner here, so I picked the easier approach.
Along with two minor improvements:
1. preserves ScalarEvolution by forgetting instructions replaced
2. removes dead code locally avoiding the need of running DCE afterwards
Test Plan: add to slsr-add.ll a test that requires multiple iterations
Reviewers: broune, dberlin, atrick, meheff
Reviewed By: atrick
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9058
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235151 91177308-0d34-0410-b5e6-96231b3b80d8
This testcase is less brittle and exactly tests for the misbehaviour.
Thanks to David Blaikie for the suggestion.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235149 91177308-0d34-0410-b5e6-96231b3b80d8
Found by code inspection, but breaking i16 at least breaks other tests.
They aren't checking this in particular though, so also add some
explicit tests for the already working types.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235148 91177308-0d34-0410-b5e6-96231b3b80d8
See r230786 and r230794 for similar changes to gep and load
respectively.
Call is a bit different because it often doesn't have a single explicit
type - usually the type is deduced from the arguments, and just the
return type is explicit. In those cases there's no need to change the
IR.
When that's not the case, the IR usually contains the pointer type of
the first operand - but since typed pointers are going away, that
representation is insufficient so I'm just stripping the "pointerness"
of the explicit type away.
This does make the IR a bit weird - it /sort of/ reads like the type of
the first operand: "call void () %x(" but %x is actually of type "void
()*" and will eventually be just of type "ptr". But this seems not too
bad and I don't think it would benefit from repeating the type
("void (), void () * %x(" and then eventually "void (), ptr %x(") as has
been done with gep and load.
This also has a side benefit: since the explicit type is no longer a
pointer, there's no ambiguity between an explicit type and a function
that returns a function pointer. Previously this case needed an explicit
type (eg: a function returning a void() function was written as
"call void () () * @x(" rather than "call void () * @x(" because of the
ambiguity between a function returning a pointer to a void() function
and a function returning void).
No ambiguity means even function pointer return types can just be
written alone, without writing the whole function's type.
This leaves /only/ the varargs case where the explicit type is required.
Given the special type syntax in call instructions, the regex-fu used
for migration was a bit more involved in its own unique way (as every
one of these is) so here it is. Use it in conjunction with the apply.sh
script and associated find/xargs commands I've provided in rr230786 to
migrate your out of tree tests. Do let me know if any of this doesn't
cover your cases & we can iterate on a more general script/regexes to
help others with out of tree tests.
About 9 test cases couldn't be automatically migrated - half of those
were functions returning function pointers, where I just had to manually
delete the function argument types now that we didn't need an explicit
function type there. The other half were typedefs of function types used
in calls - just had to manually drop the * from those.
import fileinput
import sys
import re
pat = re.compile(r'((?:=|:|^|\s)call\s(?:[^@]*?))(\s*$|\s*(?:(?:\[\[[a-zA-Z0-9_]+\]\]|[@%](?:(")?[\\\?@a-zA-Z0-9_.]*?(?(3)"|)|{{.*}}))(?:\(|$)|undef|inttoptr|bitcast|null|asm).*$)')
addrspace_end = re.compile(r"addrspace\(\d+\)\s*\*$")
func_end = re.compile("(?:void.*|\)\s*)\*$")
def conv(match, line):
if not match or re.search(addrspace_end, match.group(1)) or not re.search(func_end, match.group(1)):
return line
return line[:match.start()] + match.group(1)[:match.group(1).rfind('*')].rstrip() + match.group(2) + line[match.end():]
for line in sys.stdin:
sys.stdout.write(conv(re.search(pat, line), line))
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235145 91177308-0d34-0410-b5e6-96231b3b80d8
r235050 dropped the inlined-at field from `MDLocalVariable`, deferring
to the `!dbg` attachments. Fix `UserValue` to take the `!dbg` into
account when differentiating between variables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235140 91177308-0d34-0410-b5e6-96231b3b80d8
A big-endian vector return needs a byte-swap which we aren't doing right now.
For now just bail on these cases to get correctness back.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235133 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
If a pointer is marked as dereferenceable_or_null(N), LLVM assumes it
is either `null` or `dereferenceable(N)` or both. This change only
introduces the attribute and adds a token test case for the `llvm-as`
/ `llvm-dis`. It does not hook up other parts of the optimizer to
actually exploit the attribute -- those changes will come later.
For pointers in address space 0, `dereferenceable(N)` is now exactly
equivalent to `dereferenceable_or_null(N)` && `nonnull`. For other
address spaces, `dereferenceable(N)` is potentially weaker than
`dereferenceable_or_null(N)` && `nonnull` (since we could have a null
`dereferenceable(N)` pointer).
The motivating case for this change is Java (and other managed
languages), where pointers are either `null` or dereferenceable up to
some usually known-at-compile-time constant offset.
Reviewers: rafael, hfinkel
Reviewed By: hfinkel
Subscribers: nicholas, llvm-commits
Differential Revision: http://reviews.llvm.org/D8650
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235132 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This fixes a left-over efficiency issue in D8950.
As Andrew and Daniel suggested, we can store the candidates in a stack
and pop the top element when it does not dominate the current
instruction. This reduces the worst-case time complexity to O(n).
Test Plan: a new test in nary-add.ll that exercises this optimization.
Reviewers: broune, dberlin, meheff, atrick
Reviewed By: atrick
Subscribers: llvm-commits, sanjoy
Differential Revision: http://reviews.llvm.org/D9055
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235129 91177308-0d34-0410-b5e6-96231b3b80d8
This is very similar to D8486 / r232852 (vperm2). If we treat insertps intrinsics
as shufflevectors, we can optimize them better.
I've left all but the full zero case of the zero mask variants out of this patch.
I don't think those can be converted into a single shuffle in all cases, but I'd
be happy to be proven wrong as I was for vperm2f128.
Either way, we'd need to support whatever sequence we come up with for those cases
in the backend before converting them here.
Differential Revision: http://reviews.llvm.org/D8833
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235124 91177308-0d34-0410-b5e6-96231b3b80d8
This started failing on Windows after my switch lowering change in r235101.
I suspect the error is unrelated, so adding a triple to pacify it
until it can be fixed. See the PR for details.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235106 91177308-0d34-0410-b5e6-96231b3b80d8
This is a major rewrite of the SelectionDAG switch lowering. The previous code
would lower switches as a binary tre, discovering clusters of cases
suitable for lowering by jump tables or bit tests as it went along. To increase
the likelihood of finding jump tables, the binary tree pivot was selected to
maximize case density on both sides of the pivot.
By not selecting the pivot in the middle, the binary trees would not always
be balanced, leading to performance problems in the generated code.
This patch rewrites the lowering to search for clusters of cases
suitable for jump tables or bit tests first, and then builds the binary
tree around those clusters. This way, the binary tree will always be balanced.
This has the added benefit of decoupling the different aspects of the lowering:
tree building and jump table or bit tests finding are now easier to tweak
separately.
For example, this will enable us to balance the tree based on profile info
in the future.
The algorithm for finding jump tables is O(n^2), whereas the previous algorithm
was O(n log n) for common cases, and quadratic only in the worst-case. This
doesn't seem to be major problem in practice, e.g. compiling a file consisting
of a 10k-case switch was only 30% slower, and such large switches should be rare
in practice. Compiling e.g. gcc.c showed no compile-time difference. If this
does turn out to be a problem, we could limit the search space of the algorithm.
This commit also disables all optimizations during switch lowering in -O0.
Differential Revision: http://reviews.llvm.org/D8649
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235101 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: Previously, this was only happening for functions, but because of .insn, objects can also be marked now.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8007
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235095 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This assembler directive marks the current label as an instruction label in microMIPS and MIPS16.
This initial implementation works only for microMIPS.
Reviewers: dsanders
Reviewed By: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D8006
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235084 91177308-0d34-0410-b5e6-96231b3b80d8
Fix for test case found by James Molloy - TRUNCATE of constant build vectors can be more simply achieved by simply replacing with a new build vector node with the truncated value type - no need to touch the scalar operands at all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235079 91177308-0d34-0410-b5e6-96231b3b80d8
The only type that isn't an integer, isn't floating point, and isn't
a vector; ladies and gentlemen, the gift that keeps on giving: x86_mmx!
Fixes PR23246.
Original message (reverted in r235062):
[CodeGen] Combine concat_vectors of scalars into build_vector.
Combine something like:
(v8i8 concat_vectors (v2i8 bitcast (i16)) x4)
into:
(v8i8 (bitcast (v4i16 BUILD_VECTOR (i16) x4)))
If any of the scalars are floating point, use that throughout.
Differential Revision: http://reviews.llvm.org/D8948
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235072 91177308-0d34-0410-b5e6-96231b3b80d8
The way we split SEH catch-all blocks can leave some dead EH values
behind at -O0. Try to remove them, and if we fail, replace them all with
undef.
Fixes a crash when removing the old unreachable landingpad which is
still used by extractvalue instructions in the catch-all block.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235061 91177308-0d34-0410-b5e6-96231b3b80d8
Remove 'inlinedAt:' from MDLocalVariable. Besides saving some memory
(variables with it seem to be single largest `Metadata` contributer to
memory usage right now in -g -flto builds), this stops optimization and
backend passes from having to change local variables.
The 'inlinedAt:' field was used by the backend in two ways:
1. To tell the backend whether and into what a variable was inlined.
2. To create a unique id for each inlined variable.
Instead, rely on the 'inlinedAt:' field of the intrinsic's `!dbg`
attachment, and change the DWARF backend to use a typedef called
`InlinedVariable` which is `std::pair<MDLocalVariable*, MDLocation*>`.
This `DebugLoc` is already passed reliably through the backend (as
verified by r234021).
This commit removes the check from r234021, but I added a new check
(that will survive) in r235048, and changed the `DIBuilder` API in
r235041 to require a `!dbg` attachment whose 'scope:` is in the same
`MDSubprogram` as the variable's.
If this breaks your out-of-tree testcases, perhaps the script I used
(mdlocalvariable-drop-inlinedat.sh) will help; I'll attach it to PR22778
in a moment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235050 91177308-0d34-0410-b5e6-96231b3b80d8