If SCEV can prove that the backedge taken count for a loop is zero, it does not
need to "understand" a recursive PHI to compute its exiting value.
This should fix PR33885.
llvm-svn: 309758
In the last half-dozen commits to LLVM I removed code that became dead
after removing the offset parameter from llvm.dbg.value gradually
proceeding from IR towards the backend. Before I can move on to
DwarfDebug and friends there is one last side-called offset I need to
remove: This patch modifies PrologEpilogInserter's use of the
DBG_VALUE's offset argument to use a DIExpression instead. Because the
PrologEpilogInserter runs at the Machine level I had to play a little
trick with a named llvm.dbg.mir node to get the DIExpressions to print
in MIR dumps (which print the llvm::Module followed by the
MachineFunction dump).
I also had to add rudimentary DwarfExpression support to CodeView and
as a side-effect also fixed a bug (CodeViewDebug::collectVariableInfo
was supposed to give up on variables with complex DIExpressions, but
would fail to do so for fragments, which are also modeled as
DIExpressions).
With this last holdover removed we will have only one canonical way of
representing offsets to debug locations which will simplify the code
in DwarfDebug (and future versions of CodeViewDebug once it starts
handling more complex expressions) and make it easier to reason about.
This patch is NFC-ish: All test case changes are for assembler
comments and the binary output does not change.
rdar://problem/33580047
Differential Revision: https://reviews.llvm.org/D36125
llvm-svn: 309751
The coverage tool needs to know which slice to look at when it's handed
a universal binary. Some projects need to look at aggregate coverage
reports for a variety of slices in different binaries: this patch adds
support for these kinds of projects to llvm-cov.
rdar://problem/33579007
llvm-svn: 309747
The previous attempt, which made do with a single offset in
computeCalleeSaveRegisterPairs, wasn't quite enough. The previous
attempt only worked as long as CombineSPBump == true (since the
offset would be adjusted later in fixupCalleeSaveRestoreStackOffset).
Instead include the size for the fixed stack area used for win64
varargs in calculations in emitPrologue/emitEpilogue. The stack
consists of mainly three parts;
- AFI->getLocalStackSize()
- AFI->getCalleeSavedStackSize()
- FixedObject
Most of the places in the code which previously used the CSStackSize
now use PrologueSaveSize instead, which is the sum of the latter
two, while some cases which need exactly the middle one use
AFI->getCalleeSavedStackSize() explicitly instead of a local variable.
In addition to moving the offsetting into emitPrologue/emitEpilogue
(which fixes functions with CombineSPBump == false), also set the
frame pointer to point to the right location, where the frame pointer
and link register actually are stored. In addition to the prologue/epilogue,
this also requires changes to resolveFrameIndexReference.
Add tests for a function that keeps a frame pointer and another one
that uses a VLA.
Differential Revision: https://reviews.llvm.org/D35919
llvm-svn: 309744
The src0 register must match src1 or src2, but if these
were undefined they could end up using different implicit_defed
virtual registers. Force these to use one undef vreg or pick the
defined other register.
Also fixes producing invalid nodes without the right number of
inputs when src2 is undef.
llvm-svn: 309743
Includes a hack to fix the type selected for
the GlobalAddress of the function, which will be
fixed by changing the default datalayout to use
generic pointers for 0.
llvm-svn: 309732
Summary:
We already have information about static alloca stack locations in our
side table. Emitting instructions for them is inefficient, and it only
happens when the address of the alloca has been materialized within the
current block, which isn't often.
Reviewers: aprantl, probinson, dblaikie
Subscribers: jfb, dschuff, sbc100, jgravelle-google, hiraditya, llvm-commits, aheejin
Differential Revision: https://reviews.llvm.org/D36117
llvm-svn: 309729
Improves atom scheduler test coverage (to make it easier to upgrade them for PR32431).
Merged SSE_VEC_BIT_ITINS_P + SSE_BIT_ITINS_P as we were interchanging between them.
llvm-svn: 309715
Summary: The 64-bit 'and' with immediate instruction only supports a 32-bit immediate. So for larger constants we have to load the constant into a register first. If the immediate happens to be a mask we can use the BEXTRI instruction to perform the masking. We already do something similar using the BZHI instruction from the BMI2 instruction set.
Reviewers: RKSimon, spatel
Reviewed By: RKSimon
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36129
llvm-svn: 309706
Improves atom scheduler test coverage (to make it easier to upgrade them for PR32431).
Checked on Agner that these actually match the UNPACK schedules, but better to include a separate class
llvm-svn: 309701
Summary:
FEntryInserter pass unconditionally derefs the first Instruction
in the first Basic Block. The pass crashes when the first
BasicBlock is empty. Fix the crash by not dereferencing the basic
Block iterator. This fixes an issue observed when building Linux kernel
4.4 with clang.
Fixes PR33971.
Reviewers: hfinkel, niravd, dblaikie
Reviewed By: niravd
Subscribers: davide, llvm-commits
Differential Revision: https://reviews.llvm.org/D35979
llvm-svn: 309694
We were already using the 32 bit element opcode if BWI isn't enabled, but there's no reason to change opcode if we have BWI. We will still use the 8/16 opcodes for masked stores though.
This allows us to use the aligned opcode when we can which makes our test output more consistent between different modes. It also reduces the number of isel patterns we need.
This is a slight inconsistency with loads which default to 64 bit element opcodes. I'll probably rectify that in a future patch.
Differential Revision: https://reviews.llvm.org/D35978
llvm-svn: 309693
Summary:
As far as I can tell the earlier call getLimitedValue will guaranteed ShiftAmt is saturated to BitWidth-1 preventing it from ever being equal or greater than BitWidth.
At one point in the past the getLimitedValue call was only passed BitWidth not BitWidth - 1. This would have allowed the equality case to get here. And in fact this check was initially added as just BitWidth == ShiftAmt, but was changed shortly after to include > which should have never been possible.
Reviewers: spatel, majnemer, davide
Reviewed By: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D36123
llvm-svn: 309690
This patch enables control flow optimization for
variations of BBIT instruction. In this case
optimization removes unnecessary branch after
BBIT instruction.
Differential Revision: https://reviews.llvm.org/D35359
llvm-svn: 309679
Certain operations require vector of i1 values. However, for Hexagon
architecture compatibility, they need to be represented as vector of i8.
Patch by Suyog Sarda.
llvm-svn: 309677
This causes assertion failures in (a somewhat old version of) SpiderMonkey.
I have already forwarded reproduction instructions to the patch author.
llvm-svn: 309659
To the best of my knowledge -metarenamer is used in two cases:
1) obfuscate names, when e.g. they contain informations that
can't be shared.
2) Improve clarity of the textual IR for testcases.
One of the usecases if getting the output of `opt` and passing it
to the lli interpreter to run the test. If metarenamer renames
@main, lli can't find an entry point.
llvm-svn: 309657
Stack coloring pass need to maintain AliasAnalysis information when merging stack slots of different types.
Actually, there is a FIXME comment in StackColoring.cpp
// FIXME: In order to enable the use of TBAA when using AA in CodeGen,
// we'll also need to update the TBAA nodes in MMOs with values
// derived from the merged allocas.
But, TBAA has been already enabled in CodeGen without fixing this pass.
The incorrect TBAA metadata results in recent failures in bootstrap test on ppc64le (PR33928) by allowing unsafe instruction scheduling.
Although we observed the problem on ppc64le, this is a platform neutral issue.
This patch makes the stack coloring pass maintains AliasAnalysis information when merging multiple stack slots.
llvm-svn: 309651
https://reviews.llvm.org/D31536 didn't really solve the problem it was
trying to solve; it got rid of the assertion failure, but we were still
scheduling the DAG incorrectly (mixing together instructions from
different calls), leading to a MachineVerifier failure.
In order to schedule the DAG correctly, we have to make sure we don't
schedule a node which should be blocked by an interference. Fix
ScheduleDAGRRList::PickNodeToScheduleBottomUp so it doesn't pick a node
like that.
The added call to FindAvailableNode() is the key change here; this makes
sure we don't try to schedule a call while we're in the middle of
scheduling a different call. I'm not sure this is the right approach; in
particular, I'm not sure how to prove we don't end up with an infinite
loop of repeatedly backtracking.
This also reverts the code change from D31536. It doesn't do anything
useful: we should never schedule an ADJCALLSTACKDOWN unless we've
already scheduled the corresponding ADJCALLSTACKUP.
Differential Revision: https://reviews.llvm.org/D33818
llvm-svn: 309642
Summary:
Adding part of the changes in D30369 (needed to make progress):
Current patch updates AliasAnalysis and MemoryLocation, but does _not_ clean up MemorySSA.
Original summary from D30369, by dberlin:
Currently, we have instructions which affect memory but have no memory
location. If you call, for example, MemoryLocation::get on a fence,
it asserts. This means things specifically have to avoid that. It
also means we end up with a copy of each API, one taking a memory
location, one not.
This starts to fix that.
We add MemoryLocation::getOrNone as a new call, and reimplement the
old asserting version in terms of it.
We make MemoryLocation optional in the (Instruction, MemoryLocation)
version of getModRefInfo, and kill the old one argument version in
favor of passing None (it had one caller). Now both can handle fences
because you can just use MemoryLocation::getOrNone on an instruction
and it will return a correct answer.
We use all this to clean up part of MemorySSA that had to handle this difference.
Note that literally every actual getModRefInfo interface we have could be made private and replaced with:
getModRefInfo(Instruction, Optional<MemoryLocation>)
and
getModRefInfo(Instruction, Optional<MemoryLocation>, Instruction, Optional<MemoryLocation>)
and delegating to the right ones, if we wanted to.
I have not attempted to do this yet.
Reviewers: dberlin, davide, dblaikie
Subscribers: sanjoy, hfinkel, chandlerc, llvm-commits
Differential Revision: https://reviews.llvm.org/D35441
llvm-svn: 309641
Chromium's gold build seems to have trouble with this (gold produces
errors) - not sure if it's gold that's not coping with the valid
representation, or a bug in the implementation in LLVM, etc.
llvm-svn: 309630
When the first instruction of a basic block has no location (consider a
LEA materializing the address of an alloca for a call), we want to start
the line table for the block with the first valid source location in the
block. We need to ignore DBG_VALUE instructions during this scan to get
decent line tables.
llvm-svn: 309628