Summary:
It is pretty common to assume that something is not zero.
Even optimizer itself sometimes emits such assumptions
(e.g. `addAssumeNonNull()` in `PromoteMemoryToRegister.cpp`).
But we currently don't deal with such assumptions :)
The only way `isKnownNonZero()` handles assumptions is
by calling `computeKnownBits()` which calls `computeKnownBitsFromAssume()`.
But `x != 0` does not tell us anything about set bits,
it only says that there are *some* set bits.
So naturally, `KnownBits` does not get populated,
and we fail to make use of this assumption.
I propose to deal with this special case by special-casing it
via adding a `isKnownNonZeroFromAssume()` that returns boolean
when there is an applicable assumption.
While there, we also deal with other predicates,
mainly if the comparison is with constant.
Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=43267 | PR43267 ]].
Differential Revision: https://reviews.llvm.org/D71660
This is a pretty rare case, when CxtI and assume are
in the same basic block, with assume being located later.
We were already checking that assumption was guaranteed to be
executed, but we omitted CxtI itself from consideration,
and as the test (miscompile) shows, that is incorrect.
As noted in D71660 review by @nikic.
@escape() may throw here, we don't know that assumption, which is located
afterwards in the same block, is executed, therefore %load arg of
call to @escape() can not be marked as non-null.
As noted in D71660 review by @nikic.
A function marked `noreturn` may contain unreachable terminators: these
should not be considered cold, as the function may be a trampoline.
rdar://58068594
Recommit after making the same API change in non-x86 targets. This has been build for all targets, and tested for effected ones. Why the difference? Because my disk filled up when I tried make check for all.
For auto-padding assembler support, we'll need to bundle the label with the instructions (nops or call sequences) so that they don't get separated. This just rearranges the code to make the upcoming change more obvious.
This just updates an IRBuilder interface to take Functions instead of
Values so the type can be derived, and fixes some callsites in Clang to
call the updated API.
as it causes a layering violation/dependency cycle:
llvm/lib/CodeGen/AsmPrinter/DwarfDebug.cpp -> llvm/DebugInfo/DWARF/DWARFExpression.h
llvm/include/llvm/DebugInfo/DWARF/DWARFOptimizer.h -> llvm/CodeGen/NonRelocatableStringpool.h
This reverts commit abc7f6800d.
Summary:
When we use undefined symbol with its qualname, we are not able
to generate that symbol because of the logic of early "continue"
that skip the qualname symbol. This patch fixes it.
Differential revision: https://reviews.llvm.org/D71667
We don't yet advertise init capture packs, because I found some bugs
while testing it. We reject-valid and then crash on both of these:
template<int ...a> auto x = [...y = a] {};
template<int ...a> auto x = [y = a...] {};
For auto-padding assembler support, we'll need to bundle the label with the instructions (nops or call sequences) so that they don't get separated. This just rearranges the code to make the upcoming change more obvious.
This is in advance of assembler padding directives support where we'll need to bundle the label w/the corresponding faulting instruction to avoid padding being inserted between.
Enabling `-Wcast-qual` identified many casts in various system headers
that were dropping the `const` qualifier. Fixing those missing
qualifiers pointed out that a few of the definitions of the builtins
did not properly identify their arguments as `const` pointers. This
commit fixes those builtin definitions, and the system header files
so that they no longer drop the qualifier.
Differential Revision: https://reviews.llvm.org/D71718
Add a missing %run substitution to fread_fwrite test. This fixes
the test on NetBSD where %run disables ASLR as necessary for MSAN
to function.
Differential Revision: https://reviews.llvm.org/D71623
This fix was motivated by a crashes in expression parsing during code generation in which we had a RecordDecl that had incomplete FieldDecl. During code generation when computing the layout for the RecordDecl we crash because we have several incomplete FieldDecl.
This fixes the issue by assuring that during ImportDefinition(...) for a RecordDecl we also import the definitions for each FieldDecl.
Differential Revision: https://reviews.llvm.org/D71378
Summary: Instead of crashing due to the `llvm_unreachable`, provide a proper
error when invalid fixups/relocations are encountered.
Reviewers: asb, lenary
Reviewed By: asb
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71536
Recognize -mrecord-mcount from the command line and add a function attribute
"mrecord-mcount" when passed.
Only valid on SystemZ (when used with -mfentry).
Review: Ulrich Weigand
https://reviews.llvm.org/D71627
This patch enables the machine outliner for RISC-V and adds the
necessary logic for checking whether sequences can be safely outlined,
and describing how they should be outlined. Outlined functions are
called using the register t0 (x5) as the return address register, which
must be available for an occurrence of a sequence to be safely outlined.
Differential Revision: https://reviews.llvm.org/D66210
Though llvm-locstat is a "util" it requires llvm-dwarfdump
to be useful. So what happens now is that unless LLVM_BUILD_TOOLS
is ON llvm-locstats won't be part of the "all" target.
However given that it requires llvm-dwarfdump, this is less
confusing/build time consuming than suddenly having llvm-dwarfdump
build when all other tools are disabled.
Differential Revision: https://reviews.llvm.org/D71705
Summary:
This patch associates ordinal numbers to the DDG Nodes allowing
the builder to order nodes within a pi-block in program order. The
algorithm works by simply assuming the order in which the BBList
is fed into the builder. The builder already relies on the blocks being
in program order so that it can compute the dependencies correctly.
Similarly the order of instructions in their parent basic blocks
determine their program order.
Authored By: bmahjour
Reviewer: Meinersbur, fhahn, myhsu, xtian, dmgreen, kbarton, jdoerfert
Reviewed By: Meinersbur
Subscribers: ychen, arphaman, simoll, a.elovikov, mgorny, hiraditya, jfb, wuzish, llvm-commits, jsji, Whitney, etiotto, ppc-slack
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70986
Summary:
The default static (non-PIC, non-PIE) model for 32-bit powerpc does not
use @PLT annotations and relocations in GCC. LLVM shouldn't use @PLT
annotations either, because it breaks secure-PLT linking with (some
versions of?) GNU LD.
Update the available-externally.ll test to reflect that default mode should be
the same as the static relocation, by using the same check prefix.
Reviewed by: sfertile
Differential Revision: https://reviews.llvm.org/D70570
Summary:
Ignore looking at blocks that are unreachable from entry when
collecting candidates for hosting.
Normally the consthoist pass is executed in the llc pipeline,
just after unreachableblockelim. So it is abnormal to have code
that is unreachable from the entry block. But when running the
pass as part of opt, for example as part of fuzzy testing, we
might trigger various kinds of asserts when collecting candidates
if we include unreachable blocks in that analysis.
It seems like a waste of time to hoist constants in unreachble
blocks, so the solution is to simply ignore such blocks when
collecting the hoisting candidates.
The two added test cases used to end up in two different asserts,
and the intention with the checks is just to verify that we no
longer fail.
Fixes: PR43903
Reviewers: spatel
Reviewed By: spatel
Subscribers: hiraditya, uabelho, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D71678
The debug line verbose printing was printing the wrong values for rows
added via DW_LNE_end_sequence, because the row was being printed AFTER
its state had been reset following it being appended to the line table.
This patch fixes this issue by printing the row before appending it.
Reviewers: dblaikie, MaskRay
Differential Revision: https://reviews.llvm.org/D71664
That patch is extracted from the D70709. It moves CompileUnit, DeclContext
into llvm/DebugInfo/DWARF. It also adds new file DWARFOptimizer with
AddressesMap class. AddressesMap generalizes functionality
from RelocationManager.
Differential Revision: https://reviews.llvm.org/D71271
In certain situations after inlining and simplification we end up with
code that is _almost_ a min/max pattern, but contains constants that
have been demand-bit optimised to the wrong values, ending up with code
like:
%1 = icmp slt i32 %shr, -128
%2 = select i1 %1, i32 128, i32 %shr
%.inv = icmp sgt i32 %shr, 127
%spec.select.i = select i1 %.inv, i32 127, i32 %2
%conv7 = trunc i32 %spec.select.i to i8
This should be turned into a min/max pattern, but the -128 in the first
select was instead transformed into 128, as only the bottom byte was
ever demanded.
To fix this, I've put in further canonicalisation for the immediates of
selects, preferring to use the same value as the icmp if available.
Differential Revision: https://reviews.llvm.org/D71516
The inconsistency caused uops mode to fail on an older version of libpfm
since the dispatched_port was added as an alias for executed_port only
after v4.6.0 of libpfm.
Differential revision: https://reviews.llvm.org/D71665
Summary:
Instead of generating two i32 instructions for each load or store of a volatile
i64 value (two LDRs or STRs), now emit LDRD/STRD.
These improvements cover architectures implementing ARMv5TE or Thumb-2.
Reviewers: dmgreen, efriedma, john.brawn
Reviewed By: efriedma
Subscribers: kristof.beyls, hiraditya, llvm-commits
Tags: #llvm
Differential Revision: https://reviews.llvm.org/D70072
Roman Lebedev