If we have recognized that a conditional is constant at a particular location in the code (while trying to decide if we can simplify a conditional branch), we can eagerly replace that condition with a constant if it's definition is post dominated by the branch in question.
In practice, this ends up being a compile time savings at most. JumpThreading would have visited each using branch anyways. CVP would have visited the cmp itself again. Unless LVI gives up early, we shouldn't gain any addition power by doing this transformation early. What we do gain is simplicity and compile time.
Differential Revision: http://reviews.llvm.org/D9312
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236684 91177308-0d34-0410-b5e6-96231b3b80d8
Renames the original CreateGCStatepoint to CreateGCStatepointCall, and
moves invoke creating functionality from PlaceSafepoints.cpp to
IRBuilder.cpp.
This changes the labels generated for PlaceSafepoints/invokes.ll so use
a regex there to make the basic block labels more resilient.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236672 91177308-0d34-0410-b5e6-96231b3b80d8
Since the coverage mapping reader and the instrprof reader were
emitting a shared set of error codes, the error messages you'd get
back from llvm-cov were ambiguous about what was actually wrong. Add
another error category to fix this.
I've also improved the wording on a couple of the instrprof errors,
for consistency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236665 91177308-0d34-0410-b5e6-96231b3b80d8
Somehow I dropped this in r233585, and we haven't had `DEBUG_LOC_AGAIN`
records since. Add it back. Also tests that the output assembly looks
okay.
Fixes PR23436.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236661 91177308-0d34-0410-b5e6-96231b3b80d8
We had code such as this:
r2 = ...
t2Bcc
label1:
ldr ... r2
label2;
return r2<dead, def>
The if converter was transforming this to
r2<def> = ...
return [pred] r2<dead,def>
ldr <r2, kill>
return
which fails the machine verifier because the ldr now reads from a dead def.
The fix here detects dead defs in stepForward and passes them back to the caller in the clobbers list. The caller then clears the dead flag from the def is the value is live.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236660 91177308-0d34-0410-b5e6-96231b3b80d8
Specifically, this patch correctly respects the -demangle option,
and additionally adds a hidden --relative-address option allows
input addresses to be relative to the module load address instead
of absolute addresses into the image.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236653 91177308-0d34-0410-b5e6-96231b3b80d8
If called twice in the same BB on the same constant, FastISel::fastEmit_ri_ was marking the materialized vreg as killed on each use, instead of only the last use.
Change this to only mark the last use as killed by making earlier uses check if the vreg is already used elsewhere.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236650 91177308-0d34-0410-b5e6-96231b3b80d8
When folding a load in to another instruction, we need to fix the class of the index register
Otherwise, it could be something like GR64 not GR64_NOSP and would fail the machine verifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236644 91177308-0d34-0410-b5e6-96231b3b80d8
It's quite possible to encounter an insertvalue instruction that's more deeply
nested than the value we're looking for, but when that happens we really
mustn't compare beyond the end of the index array.
Since I couldn't see any guarantees about what comparisons std::equal makes, we
probably need to directly check the size beforehand. In practice, I suspect
most std::equal implementations would probably bail early, which would be OK.
But just in case...
rdar://20834485
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236635 91177308-0d34-0410-b5e6-96231b3b80d8
Emit the number of bytes in a `.debug_loc` entry directly. The old code
created temp labels (expensive), emitted the difference between them,
and then emitted one on each side of the relevant bytes.
(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`
(the optimized version of ld64's `-save-temps` when linking the
`verify-uselistorder` executable in an LTO bootstrap). I've hacked
`MCContext::Allocate()` to just call `malloc()` instead of using the
`BumpPtrAllocator` so that the heap profile is easier to read. As far
as peak memory is concerned, `MCContext::Allocate()` is equivalent to a
leak, since it only gets freed at process teardown.
In my heap profile, this patch drops memory usage of
`DwarfDebug::emitDebugLoc()` from 132.56 MB (11.4%) down to 29.86 MB
(2.7%) at peak memory. Some of that must be noise from `SmallVector`
(or other) allocations -- peak memory only dropped from 1160 MB down to
1100 MB -- but this nevertheless shaves 5% off the top.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236629 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When computing branch weights in BPI, we used to disallow branches with
weight 0. This is a minor nuisance, because a branch with weight 0 is
different to "don't have information". In the context of
instrumentation, it may mean "never executed", in the context of
sampling, it means "never or seldom executed".
In allowing 0 weight branches, I ran into issues with the switch
expansion code in selection DAG. It is currently hardwired to not handle
branches with weight 0. To maintain the current behaviour, I changed it
to use 1 when it finds 0, but perhaps the algorithm needs changes to
tolerate branches with weight zero.
Reviewers: hansw
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9533
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236617 91177308-0d34-0410-b5e6-96231b3b80d8
The patch disabled unrolling in loop vectorization pass when VF==1 on x86 architecture,
by setting MaxInterleaveFactor to 1. Unrolling in loop vectorization pass may introduce
the cost of overflow check, memory boundary check and extra prologue/epilogue code when
regular unroller will unroll the loop another time. Disable it when VF==1 remove the
unnecessary cost on x86. The same can be done for other platforms after verifying
interleaving/memory bound checking to be not perf critical on those platforms.
Differential Revision: http://reviews.llvm.org/D9515
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236613 91177308-0d34-0410-b5e6-96231b3b80d8
With neon enabled, we reach SelectBinaryFPOp and are able to get registers for a <2 x double> add.
However, we shouldn't actually attempt arithmetic on it as ARMIselLowering says "v2f64 is legal so that QR subregs can be extracted as f64 elements, but neither Neon nor VFP support any arithmetic operations on it."
This commit disables SelectBinaryFPOp for any vector types. There's already a FIXME to try handle neon. Doing so would require fixing this conditional which isn't safe for vectors 'VT == MVT::f64 || VT == MVT::i64'
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236609 91177308-0d34-0410-b5e6-96231b3b80d8
The initial code drop for VSX swap optimization permitted the
optimization only when all operations in a web of related computation
are lane-insensitive. For some lane-sensitive operations, we can
still permit the optimization provided that we make adjustments to
those operations. This patch adds special handling for vector splats
so that their presence doesn't kill the optimization.
Vector splats are lane-sensitive since they identify by number a
vector element to be used as the source of a splat. When swap
optimizations take place, the desired vector element will move to the
opposite doubleword of the quadword vector. We thus replace the index
I by (I + N/2) % N, where N is the number of elements in the vector.
A new test case is added to test that swap optimization succeeds when
vector splats are present, and that the proper input element is used
as the source of the splat.
An ancillary change removes SH_BUILDVEC as one of the kinds of special
handling that may be required by VSX swap optimization. From
experience with GCC, I had expected to need some modifications for
vector build operations, but I did not find that to be the case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236606 91177308-0d34-0410-b5e6-96231b3b80d8
Summary: This patch correctly handles undef case of EXTRACT_VECTOR_ELT node where the element index is constant and not less than vector size.
Test Plan:
CodeGen for X86 test included.
Also one incorrect regression test fixed.
Reviewers: qcolombet, chandlerc, hfinkel
Reviewed By: hfinkel
Subscribers: hfinkel, llvm-commits
Differential Revision: http://reviews.llvm.org/D9250
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236584 91177308-0d34-0410-b5e6-96231b3b80d8
Since r234249, i1 are sext instead of zext; because of that, doing
"CMP rN, #0; IT EQ/NE" isn't correct anymore.
"TST #1" is the conservatively correct alternative - the tradeoff being
that it doesn't have a 16-bit encoding -, so use that instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236569 91177308-0d34-0410-b5e6-96231b3b80d8
statepoint-indirect-return.ll breaks on linux systems. Delete the test
case to make the bots green while I figure out what the right fix is.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236568 91177308-0d34-0410-b5e6-96231b3b80d8
The index reg on instructions with complex address modes is a GPR64_NOSP. Constrain it to appease the machine verifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236557 91177308-0d34-0410-b5e6-96231b3b80d8
Note, this is a recommit of r236515 after fixing an error in r236514. The buildbot ran fast enough that it picked up r236514 prior to r236515 and threw an error. r236515 itself ran 'make check' without errors.
Original commit message follows:
A regmask (typically seen on a call) clobbers the set of registers it lists. The IfConverter, in UpdatePredRedefs, was handling register defs, but not regmasks.
These are slightly different to a def in that we need to add both an implicit use and def to appease the machine verifier. Otherwise, uses after the if converted call could think they are reading an undefined register.
Reviewed by Matthias Braun and Quentin Colombet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236550 91177308-0d34-0410-b5e6-96231b3b80d8
COMDAT groups which have become rendered unused because of inline are
discardable if we can prove that we've made the group empty.
This fixes PR22285.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236539 91177308-0d34-0410-b5e6-96231b3b80d8
The register set for LDMIA begins at offset 3, not 4. We were previously
missing the short encoding of this instruction in the case where the base
register was the first register in the register set.
Also clean up some dead code:
- The isARMLowRegister check is redundant with what VerifyLowRegs does;
replace with an assert.
- Remove handling of LDMDB instruction, which has no short encoding (and
does not appear in ReduceTable).
Differential Revision: http://reviews.llvm.org/D9485
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236535 91177308-0d34-0410-b5e6-96231b3b80d8
This patch makes ReplaceExtractVectorEltOfLoadWithNarrowedLoad convert
the element number from getVectorIdxTy() to PtrTy before doing pointer
arithmetic on it. This is needed on z, where element numbers are i32
but pointers are i64.
Original patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236530 91177308-0d34-0410-b5e6-96231b3b80d8
For little-endian, the function would convert (extract_vector_elt (load X), Y)
to X + Y*sizeof(elt). For big-endian it would instead use
X + sizeof(vec) - Y*sizeof(elt). The big-endian case wasn't right since
vector index order always follows memory/array order, even for big-endian.
(Note that the current handling has to be wrong for Y==0 since it would
access beyond the end of the vector.)
Original patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236529 91177308-0d34-0410-b5e6-96231b3b80d8
When lowering a load or store for TypeWidenVector, the type legalizer
would use a single load or store if the associated integer type was legal.
E.g. it would load a v4i8 as an i32 if i32 was legal.
This patch extends that behavior to promoted integers as well as legal ones.
If the integer type for the full vector width is TypePromoteInteger,
the element type is going to be TypePromoteInteger too, and it's still
better to use a single promoting load or truncating store rather than N
individual promoting loads or truncating stores. E.g. if you have a v2i8
on a target where i16 is promoted to i32, it's better to load the v2i8 as
an i16 rather than load both i8s individually.
Original patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236528 91177308-0d34-0410-b5e6-96231b3b80d8
This adds intrinsics to allow access to all of the z13 vector instructions.
Note that instructions whose semantics can be described by standard LLVM IR
do not get any intrinsics.
For each instructions whose semantics *cannot* (fully) be described, we
define an LLVM IR target-specific intrinsic that directly maps to this
instruction.
For instructions that also set the condition code, the LLVM IR intrinsic
returns the post-instruction CC value as a second result. Instruction
selection will attempt to detect code that compares that CC value against
constants and use the condition code directly instead.
Based on a patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236527 91177308-0d34-0410-b5e6-96231b3b80d8
The ABI specifies that <1 x i128> and <1 x fp128> are supposed to be
passed in vector registers. We do not yet support those types, and
some infrastructure is missing before we can do so.
In order to prevent accidentally generating code violating the ABI,
this patch adds checks to detect those types and error out if user
code attempts to use them.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236526 91177308-0d34-0410-b5e6-96231b3b80d8
The ABI allows sub-128 vectors to be passed and returned in registers,
with the vector occupying the upper part of a register. We therefore
want to legalize those types by widening the vector rather than promoting
the elements.
The patch includes some simple tests for sub-128 vectors and also tests
that we can recognize various pack sequences, some of which use sub-128
vectors as temporary results. One of these forms is based on the pack
sequences generated by llvmpipe when no intrinsics are used.
Signed unpacks are recognized as BUILD_VECTORs whose elements are
individually sign-extended. Unsigned unpacks can have the equivalent
form with zero extension, but they also occur as shuffles in which some
elements are zero.
Based on a patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236525 91177308-0d34-0410-b5e6-96231b3b80d8
The z13 vector facility includes some instructions that operate only on the
high f64 in a v2f64, effectively extending the FP register set from 16
to 32 registers. It's still better to use the old instructions if the
operands happen to fit though, since the older instructions have a shorter
encoding.
Based on a patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236524 91177308-0d34-0410-b5e6-96231b3b80d8
The architecture doesn't really have any native v4f32 operations except
v4f32->v2f64 and v2f64->v4f32 conversions, with only half of the v4f32
elements being used. Even so, using vector registers for <4 x float>
and scalarising individual operations is much better than generating
completely scalar code, since there's much less register pressure.
It's also more efficient to do v4f32 comparisons by extending to 2
v2f64s, comparing those, then packing the result.
This particularly helps with llvmpipe.
Based on a patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236523 91177308-0d34-0410-b5e6-96231b3b80d8
This adds ABI and CodeGen support for the v2f64 type, which is natively
supported by z13 instructions.
Based on a patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236522 91177308-0d34-0410-b5e6-96231b3b80d8
This the first of a series of patches to add CodeGen support exploiting
the instructions of the z13 vector facility. This patch adds support
for the native integer vector types (v16i8, v8i16, v4i32, v2i64).
When the vector facility is present, we default to the new vector ABI.
This is characterized by two major differences:
- Vector types are passed/returned in vector registers
(except for unnamed arguments of a variable-argument list function).
- Vector types are at most 8-byte aligned.
The reason for the choice of 8-byte vector alignment is that the hardware
is able to efficiently load vectors at 8-byte alignment, and the ABI only
guarantees 8-byte alignment of the stack pointer, so requiring any higher
alignment for vectors would require dynamic stack re-alignment code.
However, for compatibility with old code that may use vector types, when
*not* using the vector facility, the old alignment rules (vector types
are naturally aligned) remain in use.
These alignment rules are not only implemented at the C language level
(implemented in clang), but also at the LLVM IR level. This is done
by selecting a different DataLayout string depending on whether the
vector ABI is in effect or not.
Based on a patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236521 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds support for the z13 processor type and its vector facility,
and adds MC support for all new instructions provided by that facilily.
Apart from defining the new instructions, the main changes are:
- Adding VR128, VR64 and VR32 register classes.
- Making FP64 a subclass of VR64 and FP32 a subclass of VR32.
- Adding a D(V,B) addressing mode for scatter/gather operations
- Adding 1-, 2-, and 3-bit immediate operands for some 4-bit fields.
Until now all immediate operands have been the same width as the
underlying field (hence the assert->return change in decode[SU]ImmOperand).
In addition, sys::getHostCPUName is extended to detect running natively
on a z13 machine.
Based on a patch by Richard Sandiford.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236520 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit b27413cbfd78d959c18e713bfa271fb69e6b3303 (ie r236515).
This is to get the bots green while i investigate the failures.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236517 91177308-0d34-0410-b5e6-96231b3b80d8
A regmask (typically seen on a call) clobbers the set of registers it lists. The IfConverter, in UpdatePredRedefs, was handling register defs, but not regmasks.
These are slightly different to a def in that we need to add both an implicit use and def to appease the machine verifier. Otherwise, uses after the if converted call could think they are reading an undefined register.
Reviewed by Matthias Braun and Quentin Colombet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236515 91177308-0d34-0410-b5e6-96231b3b80d8
It got this in some cases (if one of them was an identified object), but not in all cases.
This caused stores to undef to block load-forwarding in some cases, etc.
Added test to Transforms/GVN to verify optimization occurs as expected.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236511 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r236360.
This change exposed a bug in WinEHPrepare by opting win32 code into EH
preparation. We already knew that WinEHPrepare has bugs, and is the
status quo for x64, so I don't think that's a reason to hold off on this
change. I disabled exceptions in the sanitizer tests in r236505 and an
earlier revision.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236508 91177308-0d34-0410-b5e6-96231b3b80d8
This patch introduces a new pass that computes the safe point to insert the
prologue and epilogue of the function.
The interest is to find safe points that are cheaper than the entry and exits
blocks.
As an example and to avoid regressions to be introduce, this patch also
implements the required bits to enable the shrink-wrapping pass for AArch64.
** Context **
Currently we insert the prologue and epilogue of the method/function in the
entry and exits blocks. Although this is correct, we can do a better job when
those are not immediately required and insert them at less frequently executed
places.
The job of the shrink-wrapping pass is to identify such places.
** Motivating example **
Let us consider the following function that perform a call only in one branch of
a if:
define i32 @f(i32 %a, i32 %b) {
%tmp = alloca i32, align 4
%tmp2 = icmp slt i32 %a, %b
br i1 %tmp2, label %true, label %false
true:
store i32 %a, i32* %tmp, align 4
%tmp4 = call i32 @doSomething(i32 0, i32* %tmp)
br label %false
false:
%tmp.0 = phi i32 [ %tmp4, %true ], [ %a, %0 ]
ret i32 %tmp.0
}
On AArch64 this code generates (removing the cfi directives to ease
readabilities):
_f: ; @f
; BB#0:
stp x29, x30, [sp, #-16]!
mov x29, sp
sub sp, sp, #16 ; =16
cmp w0, w1
b.ge LBB0_2
; BB#1: ; %true
stur w0, [x29, #-4]
sub x1, x29, #4 ; =4
mov w0, wzr
bl _doSomething
LBB0_2: ; %false
mov sp, x29
ldp x29, x30, [sp], #16
ret
With shrink-wrapping we could generate:
_f: ; @f
; BB#0:
cmp w0, w1
b.ge LBB0_2
; BB#1: ; %true
stp x29, x30, [sp, #-16]!
mov x29, sp
sub sp, sp, #16 ; =16
stur w0, [x29, #-4]
sub x1, x29, #4 ; =4
mov w0, wzr
bl _doSomething
add sp, x29, #16 ; =16
ldp x29, x30, [sp], #16
LBB0_2: ; %false
ret
Therefore, we would pay the overhead of setting up/destroying the frame only if
we actually do the call.
** Proposed Solution **
This patch introduces a new machine pass that perform the shrink-wrapping
analysis (See the comments at the beginning of ShrinkWrap.cpp for more details).
It then stores the safe save and restore point into the MachineFrameInfo
attached to the MachineFunction.
This information is then used by the PrologEpilogInserter (PEI) to place the
related code at the right place. This pass runs right before the PEI.
Unlike the original paper of Chow from PLDI’88, this implementation of
shrink-wrapping does not use expensive data-flow analysis and does not need hack
to properly avoid frequently executed point. Instead, it relies on dominance and
loop properties.
The pass is off by default and each target can opt-in by setting the
EnableShrinkWrap boolean to true in their derived class of TargetPassConfig.
This setting can also be overwritten on the command line by using
-enable-shrink-wrap.
Before you try out the pass for your target, make sure you properly fix your
emitProlog/emitEpilog/adjustForXXX method to cope with basic blocks that are not
necessarily the entry block.
** Design Decisions **
1. ShrinkWrap is its own pass right now. It could frankly be merged into PEI but
for debugging and clarity I thought it was best to have its own file.
2. Right now, we only support one save point and one restore point. At some
point we can expand this to several save point and restore point, the impacted
component would then be:
- The pass itself: New algorithm needed.
- MachineFrameInfo: Hold a list or set of Save/Restore point instead of one
pointer.
- PEI: Should loop over the save point and restore point.
Anyhow, at least for this first iteration, I do not believe this is interesting
to support the complex cases. We should revisit that when we motivating
examples.
Differential Revision: http://reviews.llvm.org/D9210
<rdar://problem/3201744>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236507 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
When using the N64 ABI, element-indices use the i64 type instead of i32.
In many cases, we can use iPTR to account for this but additional patterns
and pseudo's are also required.
This fixes most (but not quite all) failures in the test-suite when using
N64 and MSA together.
Reviewers: vkalintiris
Reviewed By: vkalintiris
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D9342
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236494 91177308-0d34-0410-b5e6-96231b3b80d8
and avoid cloning unused decls into every partition.
Module partitioning showed up as a source of significant overhead when I
profiled some trivial test cases. Avoiding the overhead of partitionging
for uncalled functions helps to mitigate this.
This change also means that it is no longer necessary to have a
LazyEmittingLayer underneath the CompileOnDemand layer, since the
CompileOnDemandLayer will not extract or emit function bodies until they are
called.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236465 91177308-0d34-0410-b5e6-96231b3b80d8
These changes allow usages where you want to pass an additional
commandline option to all invocations of a specific llvm tool. Example:
> llvm-lit -Dllc=llc -enable-misched -verify-machineinstrs
Differential Revision: http://reviews.llvm.org/D9487
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@236461 91177308-0d34-0410-b5e6-96231b3b80d8
