rather than 'unsigned' for their costs.
For something like costs in particular there is a natural "negative"
value, that of savings or saved cost. As a consequence, there is a lot
of code that subtracts or creates negative values based on cost, all of
which is prone to awkwardness or bugs when dealing with an unsigned
type. Similarly, we *never* want these values to wrap, as that would
cause Very Bad code generation (likely percieved as an infinite loop as
we try to emit over 2^32 instructions or some such insanity).
All around 'int' seems a much better fit for these basic metrics. I've
added asserts to ensure that at least the TTI interface never returns
negative numbers here. If we ever have a use case for negative numbers,
we can remove this, but this way a bug where someone used '-1' to
produce a 'very large' cost will be caught by the assert.
This passes all tests, and is also UBSan clean.
No functional change intended.
Differential Revision: http://reviews.llvm.org/D11741
llvm-svn: 244080
In PR24288 it was pointed out that the easy case of a non-escaping
global and something that *obviously* required an escape sometimes is
hidden behind PHIs (or selects in theory). Because we have this binary
test, we can easily just check that all possible input values satisfy
the requirement. This is done with a (very small) recursion through PHIs
and selects. With this, the specific example from the PR is correctly
folded by GVN.
Differential Revision: http://reviews.llvm.org/D11707
llvm-svn: 244078
To get the successors of a BB we currently do successors(BB) which
ultimately walks the successors of the BB's terminator.
This moves the iterator to TerminatorInst as thats what we're actually
using to do the iteration, and adds a member function to TerminatorInst
to allow us to iterate directly over successors given an instruction.
For example, we can now do
for (auto *Succ : BI->successors())
instead of
for (unsigned i = 0, e = BI->getNumSuccessors(); i != e; ++i)
Reviewed by Tobias Grosser.
llvm-svn: 244074
On Darwin, it is required to stamp the object file with VERSION_MIN load
command. This commit will provide a VERSRION_MIN load command to the
MachO file that doesn't specify the version itself by inferring from
Target Triple.
llvm-svn: 244059
Summary: Among other things, this allows -print-after-all/-print-before-all to
dump IR around this pass.
IIRC, this pass is off by default, but it's still helpful when debugging.
llvm-svn: 244056
We can't propagate FMF partially without breaking DAG-level CSE. We either need to
relax CSE to account for mismatched FMF as a temporary work-around or fully propagate
FMF throughout the DAG.
Surprisingly, there are no existing regression tests for this, but here's an example:
define float @fmf(float %a, float %b) {
%mul1 = fmul fast float %a, %b
%nega = fsub fast float 0.0, %a
%mul2 = fmul fast float %nega, %b
%abx2 = fsub fast float %mul1, %mul2
ret float %abx2
}
$ llc -o - badflags.ll -march=x86-64 -mattr=fma -enable-unsafe-fp-math -enable-fmf-dag=0
...
vmulss %xmm1, %xmm0, %xmm0
vaddss %xmm0, %xmm0, %xmm0
retq
$ llc -o - badflags.ll -march=x86-64 -mattr=fma -enable-unsafe-fp-math -enable-fmf-dag=1
...
vmulss %xmm1, %xmm0, %xmm2
vfmadd213ss %xmm2, %xmm1, %xmm0 <--- failed to recognize that (a * b) was already calculated
retq
llvm-svn: 244053
Summary: Among other things, this allows -print-after-all/-print-before-all to
dump IR around this pass.
This is the AArch64 version of r243052.
llvm-svn: 244041
return StringSwitch<int>(Flags)
.Case("g", 0x1)
.Case("nzcvq", 0x2)
.Case("nzcvqg", 0x3)
.Default(-1);
...
// The _g and _nzcvqg versions are only valid if the DSP extension is
// available.
if (!Subtarget->hasThumb2DSP() && (Mask & 0x2))
return -1;
ARMARM confirms that the comment is right, and the code was wrong.
llvm-svn: 244029
In r242277, I updated the MachineCombiner to work with itineraries, but I
missed a call that is scheduling-model-only (the opcode-only form of
computeInstrLatency). Using the form that takes an MI* allows this to work with
itineraries (and should be NFC for subtargets with scheduling models).
llvm-svn: 244020
Previously we kept going on partly corrupted input, which might result
in garbage being printed, or even worse, random crashes.
Rafael mentioned that this is the GNU behavior as well, but after some
discussion we both agreed it's probably better to emit a reasonable
error message and exit. As a side-effect of this commit, now we don't
rely on global state for error codes anymore. objdump was the last tool
in the toolchain which needed to be converted. Hopefully the old behavior
won't sneak into the tree again.
llvm-svn: 244019
For example of mingw-w64-g++-4.8.1,
llvm/unittests/ADT/ArrayRefTest.cpp: In member function 'virtual void {anonymous}::ArrayRefTest_AllocatorCopy_Test::TestBody()':
llvm/unittests/ADT/ArrayRefTest.cpp:56:40: internal compiler error: in count_type_elements, at expr.c:5523
} Array3Src[] = {{"hello"}, {"world"}};
^
Please submit a full bug report,
with preprocessed source if appropriate.
llvm-svn: 244017
As documented in the LLVM Coding Standards, indeed MSVC incorrectly asserts
on this in Debug mode. This happens when building clang with Visual C++ and
-triple i686-pc-windows-gnu on these clang regression tests:
clang/test/CodeGen/2011-03-08-ZeroFieldUnionInitializer.c
clang/test/CodeGen/empty-union-init.c
llvm-svn: 243996
Create wrapper methods in the Function class for the OptimizeForSize and MinSize
attributes. We want to hide the logic of "or'ing" them together when optimizing
just for size (-Os).
Currently, we are not consistent about this and rely on a front-end to always set
OptimizeForSize (-Os) if MinSize (-Oz) is on. Thus, there are 18 FIXME changes here
that should be added as follow-on patches with regression tests.
This patch is NFC-intended: it just replaces existing direct accesses of the attributes
by the equivalent wrapper call.
Differential Revision: http://reviews.llvm.org/D11734
llvm-svn: 243994
In the commentary for D11660, I wasn't sure if it was alright to create new
integer machine instructions without also creating the implicit EFLAGS operand.
From what I can see, the implicit operand is always created by the MachineInstrBuilder
based on the instruction type, so we don't have to do that explicitly. However, in
reviewing the debug output, I noticed that the operand was not marked as 'dead'.
The machine combiner should do that to preserve future optimization opportunities
that may be checking for that dead EFLAGS operand themselves.
Differential Revision: http://reviews.llvm.org/D11696
llvm-svn: 243990
Summary:
Previously, we would check whether the target is supported or not, only in
fastSelectInstruction(). This means that 64-bit targets could use FastISel too.
We fix this by checking every overridden method of the FastISel class and
by falling back to SelectionDAG if the target isn't supported. This change
should have been committed along with r243638, but somehow I missed it.
Reviewers: dsanders
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D11755
llvm-svn: 243986
It introduced two regressions on 64-bit big-endian targets running under N32
(MultiSource/Benchmarks/tramp3d-v4/tramp3d-v4, and
MultiSource/Applications/kimwitu++/kc) The issue is that on 64-bit targets
comparisons such as BEQ compare the whole GPR64 but incorrectly tell the
instruction selector that they operate on GPR32's. This leads to the
elimination of i32->i64 extensions that are actually required by
comparisons to work correctly.
There's currently a patch under review that fixes this problem.
llvm-svn: 243984
r243883 and r243961 made a use-after-free far more likely:
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux-fast/builds/6041/steps/check-llvm%20asan/logs/stdio
Unresolved nodes get inserted into the `Cycles` array. If they later
get resolved through RAUW, we need to update the reference. It's
interesting that this never hit before (maybe an asan-ified clang
bootstrap with `-flto -g` would have hit it, but I admit I haven't tried
anything quite that crazy).
llvm-svn: 243976
