Normally an ELF .o has two string tables, one for symbols, one for section
names.
With the scheme of naming sections like ".text.foo" where foo is a symbol,
there is a big potential saving in using a single one.
Building llvm+clang+lld with master and with this patch the results were:
master: 193,267,008 bytes
patch: 186,107,952 bytes
master non unique section names: 183,260,192 bytes
patch non unique section names: 183,118,632 bytes
So using non usique saves 10,006,816 bytes, and the patch saves 7,159,056 while
still using distinct names for the sections.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238073 91177308-0d34-0410-b5e6-96231b3b80d8
This patch extends EarlyCSE to take advantage of the information that a controlling branch gives us about the value of a Value within this and dominated basic blocks. If the current block has a single predecessor with a controlling branch, we can infer what the branch condition must have been to execute this block. The actual change to support this is downright simple because EarlyCSE's existing scoped hash table logic deals with most of the complexity around merging.
The patch actually implements two optimizations.
1) The first is analogous to JumpThreading in that it enables EarlyCSE's CSE handling to fold branches which are exactly redundant due to a previous branch to branches on constants. (It doesn't actually replace the branch or change the CFG.) This is pretty clearly a win since it enables substantial CFG simplification before we start trying to inline.
2) The second is analogous to CVP in that it exploits the knowledge gained to replace dominated *uses* of the original value. EarlyCSE does not otherwise reason about specific uses, so this is the more arguable one. It does enable further simplication and constant folding within the rest of the visit by EarlyCSE.
In both cases, the added code only handles the easy dominance based case of each optimization. The general case is deferred to the existing passes.
Differential Revision: http://reviews.llvm.org/D9763
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238071 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombine transforms A *nsw B +nsw A *nsw C to A *nsw (B + C).
This is incorrect -- e.g. if A = -1, B = 1, C = INT_SMAX. Then
nothing in the LHS overflows, but the multiplication in RHS overflows.
We need to first make sure that we won't multiple by INT_SMAX + 1.
Test case `add_of_mul` contributed by Sanjoy Das.
This fixes PR23635.
Differential Revision: http://reviews.llvm.org/D9629
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238066 91177308-0d34-0410-b5e6-96231b3b80d8
The usual CodeGenPrepare trickery, on a target-specific intrinsic.
Without this, the expansion of atomics will usually have the zext
be hoisted out of the loop, defeating the various patterns we have
to catch this precise case.
Differential Revision: http://reviews.llvm.org/D9930
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238054 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds a class for processing many recip codegen possibilities.
The TargetRecip class is intended to handle both command-line options to llc as well
as options passed in from a front-end such as clang with the -mrecip option.
The x86 backend is updated to use the new functionality.
Only -mcpu=btver2 with -ffast-math should see a functional change from this patch.
All other CPUs continue to *not* use reciprocal estimates by default with -ffast-math.
Differential Revision: http://reviews.llvm.org/D8982
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238051 91177308-0d34-0410-b5e6-96231b3b80d8
Before, getCanonicalArchName was relying on parseArch() to validate the arch
name, which was a problem when other methods, that also needed to call it,
were duplicating the steps.
But to dissociate getCanonicalArchName from parseArch, we needed to make
getCanonicalArchName more robust in detecting valid arch names. It's still
not perfect, but will do for the time being, until we merge Triple with
TargetParser into a TargetDescription mega class.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238047 91177308-0d34-0410-b5e6-96231b3b80d8
The 'off' field of 'struct bpf_insn' is in cpu-endianness,
since the rest is emitted as little endian, make sure
that 'off' field is little endian as well.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238038 91177308-0d34-0410-b5e6-96231b3b80d8
This allows us to match armv6m to default to thumb, but will also be used by
Clang's driver and remove the current incomplete copy in it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238036 91177308-0d34-0410-b5e6-96231b3b80d8
The problem was that I slipped a change required for shrink-wrapping, namely I
used getFirstTerminator instead of the getLastNonDebugInstr that was here before
the refactoring, whereas the surrounding code is not yet patched for that.
Original message:
[X86] Refactor the prologue emission to prepare for shrink-wrapping.
- Add a late pass to expand pseudo instructions (tail call and EH returns).
Instead of doing it in the prologue emission.
- Factor some static methods in X86FrameLowering to ease code sharing.
NFC.
Related to <rdar://problem/20821487>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238035 91177308-0d34-0410-b5e6-96231b3b80d8
accumulating estimated cost, and other loop-centric logic from the logic
used to analyze instructions in a particular iteration.
This makes the visitor very narrow in scope -- all it does is visit
instructions, update a map of simplified values, and return whether it
is able to optimize away a particular instruction.
The two cost metrics are now returned as an optional struct. When the
optional is left unengaged, there is no information about the unrolled
cost of the loop, when it is engaged the cost metrics are available to
run against the thresholds.
No functionality changed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238033 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds support for the ISA 2.07 additions involving the
branch history rolling buffer and event-based branching. These will
not be used by typical applications, so built-in support is not
required. They will only be available via inline assembly.
Assembly/disassembly tests are included in the patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238032 91177308-0d34-0410-b5e6-96231b3b80d8
MachO and COFF quite reasonably only define the size for common symbols.
We used to try to figure out the "size" by computing the gap from one symbol to
the next.
This would not be correct in general, since a part of a section can belong to no
visible symbol (padding, private globals).
It was also really expensive, since we would walk every symbol to find the size
of one.
If a caller really wants this, it can sort all the symbols once and get all the
gaps ("size") in O(n log n) instead of O(n^2).
On MachO this also has the advantage of centralizing all the checks for an
invalid n_sect.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238028 91177308-0d34-0410-b5e6-96231b3b80d8
The list of subtarget features for the 7em triple contains 't2xtpk',
which actually disables that subtarget feature. Correct that to
'+t2xtpk' and test that the instructions enabled by that feature do
actually work.
Differential Revision: http://reviews.llvm.org/D9936
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238022 91177308-0d34-0410-b5e6-96231b3b80d8
This change to VirtRegRewriter::addMBBLiveIns adds live-in registers for each
MachineBasicBlock's LiveIns set without isLiveIn checks as they are being added
because doing so is expensive. After all live-in registers are added, the LiveIn
vectors are sorted and uniqued.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238008 91177308-0d34-0410-b5e6-96231b3b80d8
Shave a pointer off of `MCSymbolName` by storing `StringMapEntry<bool>*`
instead of `StringRef`. This brings `sizeof(MCSymbol)` down to 64 on
64-bit platforms, a nice round number. My profile showed memory
dropping from 914 MB down to 908 MB, roughly 0.7%. Other than memory
usage, no functionality change here.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238005 91177308-0d34-0410-b5e6-96231b3b80d8
Lift `MCSymbolData::Index` up a level to `MCSymbol`, as preparation for
packing it into the bitfield in `MCSymbol`.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238001 91177308-0d34-0410-b5e6-96231b3b80d8
Previously `SDDbgValue`s used the general allocator that lives for all
of `SelectionDAG`. Instead, give them their own allocator, and reset it
whenever `SDDbgInfo::clear()` is called, plugging a spiritual leak.
This drops `SelectionDAGBuilder::visitIntrinsicCall()` off of my heap
profile (was at around 2% of `llc` for codegen of `-flto -g`). Thanks
to Pete Cooper for spotting the problem and suggesting the fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237998 91177308-0d34-0410-b5e6-96231b3b80d8
Cleanup how `SDDbgValue` is initialized, and rearrange the fields to
save two pointers in the struct layout. No real functionality change
though (and I doubt the memory savings would show up in a profile).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237997 91177308-0d34-0410-b5e6-96231b3b80d8
This change does a few things:
- Move some InstCombine transforms to InstSimplify
- Run SimplifyCall from within InstCombine::visitCallInst
- Teach InstSimplify to fold [us]mul_with_overflow(X, undef) to 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237995 91177308-0d34-0410-b5e6-96231b3b80d8
problem instead of suggesting doing something that is trivial to do but
incorrect given the current design of the libraries.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237994 91177308-0d34-0410-b5e6-96231b3b80d8
simplified model for use simulating each iteration into a separate
helper function that just returns the cache.
Building this cache had nothing to do with the rest of the unroll
analysis and so this removes an unnecessary coupling, etc. It should
also make it easier to think about the concept of providing fast cached
access to basic SCEV models as an orthogonal concept to the overall
unroll simulation.
I'd really like to see this kind of caching logic folded into SCEV
itself, it seems weird for us to provide it at this layer rather than
making repeated queries into SCEV fast all on their own.
No functionality changed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237993 91177308-0d34-0410-b5e6-96231b3b80d8
a single location.
This reduces code duplication a bit and will also pave the way for
a better separation between the visitation algorithm and the unroll
analysis.
No functionality changed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237990 91177308-0d34-0410-b5e6-96231b3b80d8
PR23608 pointed out that using the preheader to gain a context instruction isn't always legal because a loop might not have a preheader. When looking into that, I realized that using the preheader to determine legality for sinking is questionable at best. Given no test covers that case and the original commit didn't seem to intend it, I restructured the code to only ask context sensative queries for hoising of loads and stores. This is effectively a partial revert of 237593.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237985 91177308-0d34-0410-b5e6-96231b3b80d8
- Add a late pass to expand pseudo instructions (tail call and EH returns).
Instead of doing it in the prologue emission.
- Factor some static methods in X86FrameLowering to ease code sharing.
NFC.
Related to <rdar://problem/20821487>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237977 91177308-0d34-0410-b5e6-96231b3b80d8
Unfortunately, I can't reduce a small test case for this (although compiling
mpfr-3.1.2 with -O2 -mcpu=a2 would fairly reliably trigger a crash), but the
problem is fairly clear (at least once you know you're looking for one). If the
TLS instruction being replaced was at the end of the block, we'd increment the
iterator past it (so it would then point to MBB.end()), and then we'd increment
it again as part of the for statement, thus overrunning the end of the list.
Don't do that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237974 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
x = &a[i];
y = &a[i + j];
=>
y = x + j;
along with some refactoring work such as extracting method
findClosestMatchingDominator.
Depends on D9786 which provides the ScalarEvolution::getGEPExpr interface.
Test Plan: nary-gep.ll
Reviewers: meheff, broune
Reviewed By: broune
Subscribers: jholewinski, llvm-commits
Differential Revision: http://reviews.llvm.org/D9802
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237971 91177308-0d34-0410-b5e6-96231b3b80d8
A refactoring made @llvm.ssub.with.overflow.i32(i32 %X, i32 0) transform
into undef instead of %X.
This fixes PR23624.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237968 91177308-0d34-0410-b5e6-96231b3b80d8
This is consistent with other uses of the operand list. I'm planning a future commit where this will actually matter.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237967 91177308-0d34-0410-b5e6-96231b3b80d8
Prior to this patch, we could update the operand of another MI in the same
bundle.
Longer version:
Before InlineSpiller rematerializes a vreg, it iterates over operands of each MI
in a bundle, collecting all (MI, OpNo) pairs that reference that vreg.
Then if it does rematerialize, it goes through the pair list and replaces the
operands with the new (rematerialized) vreg. The problem is, it tries to
replace all of these operands in the main MI ! This works fine for single MIs.
However, if we are processing a bundle of MIs and the list contains multiple
pairs - the rematerialization will either crash trying to access a non-existing
operand of the main MI, or silently corrupt one of the existing ones. It will
also ignore other MIs in the bundle.
The obvious fix is to use the MI pointers saved in collected (MI, OpNo) pairs.
This must have been the original intent of the pair list but somehow these
pointers got lost.
Patch by Dmitri Shtilman <dshtilman@icloud.com>!
Differential revision: http://reviews.llvm.org/D9904
<rdar://problem/21002163>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237964 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This supersedes http://reviews.llvm.org/D4010, hopefully properly
dealing with the JIT case and also adds an actual test case.
DwarfContext was basically already usable for the JIT (and back when
we were overwriting ELF files it actually worked out of the box by
accident), but in order to resolve relocations correctly it needs
to know the load address of the section.
Rather than trying to get this out of the ObjectFile or requiring
the user to create a new ObjectFile just to get some debug info,
this adds the capability to pass in that info directly.
As part of this I separated out part of the LoadedObjectInfo struct
from RuntimeDyld, since it is now required at a higher layer.
Reviewers: lhames, echristo
Reviewed By: echristo
Subscribers: vtjnash, friss, rafael, llvm-commits
Differential Revision: http://reviews.llvm.org/D6961
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237961 91177308-0d34-0410-b5e6-96231b3b80d8
The raw non-instruction/constant form of this is still relying on being
able to access the pointee type from a pointer type - those will be
cleaned up later. For now, just focus on the cases where the pointee
type is easily accessible.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237958 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is a 2nd attempt at committing the initial MIR serialization patch.
The first commit (r237708) made the incremental buildbots unstable and was
reverted in r237730. The original commit didn't add a terminating null
character to the LLVM IR source which was passed to LLParser, and this
sometimes caused the test 'llvmIR.mir' to fail with a parsing error because
the LLVM IR source didn't have a null character immediately after the end
and thus LLLexer encountered some garbage characters that ultimately caused
the error.
This commit also includes the other test fixes I committed in
r237712 (llc path fix) and r237723 (remove target triple) which
also got reverted in r237730.
--Original Commit Message--
MIR Serialization: print and parse LLVM IR using MIR format.
This commit is the initial commit for the MIR serialization project.
It creates a new library under CodeGen called 'MIR'. This new
library adds a new machine function pass that prints out the LLVM IR
using the MIR format. This pass is then added as a last pass when a
'stop-after' option is used in llc. The new library adds the initial
functionality for parsing of MIR files as well. This commit also
extends the llc tool so that it can recognize and parse MIR input files.
Reviewers: Duncan P. N. Exon Smith, Matthias Braun, Philip Reames
Differential Revision: http://reviews.llvm.org/D9616
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@237954 91177308-0d34-0410-b5e6-96231b3b80d8