This reverts commit 15bc4dc9a8949f9cffd46ec647baf0818d28fb28.
clang-cmake-x86_64-sde-avx512-linux buildbot reported quite a few
compile-time regressions in test-suite, will investigate.
Related to D69686. As noted there, LVI currently behaves differently
for integer and pointer values: For integers, the block value is always
valid inside the basic block, while for pointers it is only valid at
the end of the basic block. I believe the integer behavior is the
correct one, and CVP relies on it via its getConstantRange() uses.
The reason for the special pointer behavior is that LVI checks whether
a pointer is dereferenced in a given basic block and marks it as
non-null in that case. Of course, this information is valid only after
the dereferencing instruction, or in conservative approximation,
at the end of the block.
This patch changes the treatment of dereferencability: Instead of
including it inside the block value, we instead treat it as something
similar to an assume (it essentially is a non-nullness assume) and
incorporate this information in intersectAssumeOrGuardBlockValueConstantRange()
if the context instruction is the terminator of the basic block.
This happens either when determining an edge-value internally in LVI,
or when a terminator was explicitly passed to getValueAt(). The latter
case makes this change not fully NFC, because we can now fold
terminator icmps based on the dereferencability information in the
same block. This is the reason why I changed one JumpThreading test
(it would optimize the condition away without the change).
Of course, we do not want to recompute dereferencability on each
intersectAssume call, so we need a new cache for this. The
dereferencability analysis requires walking the entire basic block
and computing underlying objects of all memory operands. This was
previously done separately for each queried pointer value. In the
new implementation (both because this makes the caching simpler,
and because it is faster), I instead only walk the full BB once and
cache all the dereferenced pointers. So the traversal is now performed
only once per BB, instead of once per queried pointer value.
I think the overall model now makes more sense than before, and there
will be no more pitfalls due to differing integer/pointer behavior.
Differential Revision: https://reviews.llvm.org/D69914
This patch implements a correct, but not terribly useful, transform. In particular, if we have a dynamic alloca in a loop which is guaranteed to execute, and provably not captured, we hoist the alloca out of the loop. The capture tracking is needed so that we can prove that each previous stack region dies before the next one is allocated. The transform decreases the amount of stack allocation needed by a linear factor (e.g. the iteration count of the loop).
Now, I really hope no one is actually using dynamic allocas. As such, why this patch?
Well, the actual problem I'm hoping to make progress on is allocation hoisting. There's a large draft patch out for review (https://reviews.llvm.org/D60056), and this patch was the smallest chunk of testable functionality I could come up with which takes a step vaguely in that direction.
Once this is in, it makes motivating the changes to capture tracking mentioned in TODOs testable. After that, I hope to extend this to trivial malloc free regions (i.e. free dominating all loop exits) and allocation functions for GCed languages.
Differential Revision: https://reviews.llvm.org/D69227
The change itself is straight forward and obvious, but ... there's an existing test checking for exactly the opposite. Both I and Artur think this is simply conservatism in the initial implementation. If anyone bisects a problem to this, a counter example will be very interesting.
Differential Revision: https://reviews.llvm.org/D69907
ShuffleVectorInst::isExtractSubvectorMask, introduced in
[CostModel] Add SK_ExtractSubvector handling to getInstructionThroughput (PR39368)
erroneously thought that
%340 = shufflevector <4 x float> %339, <4 x float> undef, <3 x i32> <i32 2, i32 3, i32 undef>
is a subvector extract, even though it goes off the end of the parent
vector with the undef index. That then caused an assert in
BasicTTIImplBase::getExtractSubvectorOverhead.
This commit fixes that, by not considering the above a subvector
extract.
Differential Revision: https://reviews.llvm.org/D70005
Change-Id: I87b8b00b24bef19ffc9a1b82ef4eca3b8a246eaf
We lower known CR bit spills (CRSET/CRUNSET) to load and spill the known value
but forgot to remove the redundant spills.
e.g., This sequence was used to spill a CRUNSET:
crclr 4*cr5+lt
mfocrf r3,4
rlwinm r3,r3,20,0,0
stw r3,132(r1)
Custom lowering of known CR bit spills lower it to:
crxor 4*cr5+lt, 4*cr5+lt, 4*cr5+lt
li r3,0
stw r3,132(r1)
crxor is redundant if there is no use of 4*cr5+lt so we should remove it
Differential revision: https://reviews.llvm.org/D67722
Summary:
To be used in `ConstantRange::mulWithNoOverflow()`,
may in future be useful for when saturating shift/mul ops are added.
These are precise as far as i can tell.
I initially though i will need `APInt::[us]mul_sat()` for these,
but it turned out much simpler to do what `ConstantRange::multiply()`
does - perform multiplication in twice the bitwidth, and then truncate.
Though here we want saturating signed truncation.
Reviewers: nikic, reames, spatel
Reviewed By: nikic
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69994
Summary:
The signed one is needed for implementation of `ConstantRange::smul_sat()`,
unsigned is for completeness only.
Reviewers: nikic, RKSimon, spatel
Reviewed By: nikic
Subscribers: hiraditya, dexonsmith, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69993
This required adding support for resolving R_AARCH64_ABS64 relocations to
get accurate addresses for function names to resolve.
Authored by: ianlevesque (Ian Levesque)
Reviewers: dberris, phosek, smeenai, tetsuo-cpp
Differential Revision: https://reviews.llvm.org/D69967
Summary:
We are using symbols to represent label and csect interchangeably before, and that could be a problem.
There are cases we would need to add storage mapping class to the symbol if that symbol is actually the name of a csect, but it's hard for us to figure out whether that symbol is a label or csect.
This patch intend to do the following:
1. Construct a QualName (A name include the storage mapping class)
MCSymbolXCOFF for every MCSectionXCOFF.
2. Keep a pointer to that QualName inside of MCSectionXCOFF.
3. Use that QualName whenever we need a symbol refers to that
MCSectionXCOFF.
4. Adapt the snowball effect from the above changes in
XCOFFObjectWriter.cpp.
Reviewers: xingxue, DiggerLin, sfertile, daltenty, hubert.reinterpretcast
Reviewed By: DiggerLin, daltenty
Subscribers: wuzish, nemanjai, mgorny, hiraditya, kbarton, jsji, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69633
This recommits 100e797adb433724a17c9b42b6533cd634cb796b (reverted in
009e032634b3bd7fc32071ac2344b12142286477 for failing an assert). While the
root cause was independently reverted in eaff3004019f97c64c88ab76da6b25106b659b30,
this commit includes a LIT to make sure IVDescriptor's SinkAfter logic does not
try to sink branch instructions.
Refactor usage of isCopyInstrImpl, isCopyInstr and isAddImmediate methods
to return optional machine operand pair of destination and source
registers.
Patch by Nikola Prica
Differential Revision: https://reviews.llvm.org/D69622
This triggered asserts in the Chromium build, see https://crbug.com/1022729 for
details and reproducer.
> Without this change, when a nested tag type of any kind (enum, class,
> struct, union) is used as a variable type, it is emitted without
> emitting the parent type. In CodeView, parent types point to their inner
> types, and inner types do not point back to their parents. We already
> walk over all of the parent scopes to build the fully qualified name.
> This change simply requests their type indices as we go along to enusre
> they are all emitted.
>
> Fixes PR43905
>
> Reviewers: akhuang, amccarth
>
> Differential Revision: https://reviews.llvm.org/D69924
The following testcase
function:
.Lpcrel_label1:
auipc a0, %pcrel_hi(other_function)
addi a1, a0, %pcrel_lo(.Lpcrel_label1)
.p2align 2 # Causes a new fragment to be emitted
.type other_function,@function
other_function:
ret
exposes an odd behaviour in which only the %pcrel_hi relocation is
evaluated but not the %pcrel_lo.
$ llvm-mc -triple riscv64 -filetype obj t.s | llvm-objdump -d -r -
<stdin>: file format ELF64-riscv
Disassembly of section .text:
0000000000000000 function:
0: 17 05 00 00 auipc a0, 0
4: 93 05 05 00 mv a1, a0
0000000000000004: R_RISCV_PCREL_LO12_I other_function+4
0000000000000008 other_function:
8: 67 80 00 00 ret
The reason seems to be that in RISCVAsmBackend::shouldForceRelocation we
only consider the fragment but in RISCVMCExpr::evaluatePCRelLo we
consider the section. This usually works but there are cases where the
section may still be the same but the fragment may be another one. In
that case we end forcing a %pcrel_lo relocation without any %pcrel_hi.
This patch makes RISCVAsmBackend::shouldForceRelocation use the section,
if any, to determine if the relocation must be forced or not.
Differential Revision: https://reviews.llvm.org/D60657
Summary:
To be used in `ConstantRange::shlWithNoOverflow()`,
may in future be useful for when saturating shift/mul ops are added.
Unlike `ConstantRange::shl()`, these are precise.
Reviewers: nikic, spatel, reames
Reviewed By: nikic
Subscribers: hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69960
This option allows the user to specify the use of absolute jumptables instead
of relative which is the default on most PPC subtargets.
Patch by Kamauu Bridgeman
Differential revision: https://reviews.llvm.org/D69108
x86_mmx is conceptually a vector already. Don't introduce an extra conversion between it and scalar i64.
I'm using VectorType::isValidElementType which checks for floating point, integer, and pointers to hopefully make this more readable than just blacklisting x86_mmx.
Differential Revision: https://reviews.llvm.org/D69964
Summary:
I need to make use of this pass from a driver program that isn't opt.
Therefore this patch moves this pass into the LLVM library so that it is
available for use elsewhere.
There was one function I kept in tools/opt which is exportDebugifyStats()
this is because it's serializing the statistics into a human readable
format and this seemed more in keeping with opt than a library function
Reviewers: vsk, aprantl
Subscribers: mgorny, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D69926
Without this change, when a nested tag type of any kind (enum, class,
struct, union) is used as a variable type, it is emitted without
emitting the parent type. In CodeView, parent types point to their inner
types, and inner types do not point back to their parents. We already
walk over all of the parent scopes to build the fully qualified name.
This change simply requests their type indices as we go along to enusre
they are all emitted.
Fixes PR43905
Reviewers: akhuang, amccarth
Differential Revision: https://reviews.llvm.org/D69924
As the test cases show, we end up with an insert/extract and a
bitcast to/from i64. x86_mmx is for some purposes conceptually a
vector. We shouldn't be adding scalar conversions around it.
Since _m64 is defined as <1 x i64> and intrinsics use x86_mmx
as their input/output these extra scalar operations prevent
the X86 backend from generating good code especially on 32-bit
targets where i64 gets split.
Instcombiner pass was erasing trivially dead instruction without updating dependent llvm.dbg.value.
which was not showing programmer current state of variables while debugging.
As a part of this fix I did following,
Iterate throught all the users (llvm.dbg) of a instruction which is trivially dead and set each if them undef, Before deleting the instruction.
Now user will see optimized out, when try to print those variables.
This fixes
https://bugs.llvm.org/show_bug.cgi?id=43893
This is my first fix to llvm.
Patch by kamlesh kumar!
Differential Revision: https://reviews.llvm.org/D69809
