Dorit Nuzman [Sun, 10 Dec 2017 11:13:35 +0000 (11:13 +0000)]
[SCEV] Fix wrong Equal predicate created in getAddRecForPhiWithCasts
CreateAddRecFromPHIWithCastsImpl() adds an IncrementNUSW overflow predicate
which allows the PSCEV rewriter to rewrite this scev expression:
(zext i8 {0, + , (trunc i32 step to i8)} to i32)
into
{0, +, (sext i8 (trunc i32 step to i8) to i32)}
But then it adds the wrong Equal predicate:
%step == (zext i8 (trunc i32 %step to i8) to i32).
instead of:
%step == (sext i8 (trunc i32 %step to i8) to i32)
Simon Dardis [Sat, 9 Dec 2017 23:25:57 +0000 (23:25 +0000)]
Infer lowest bits of an integer Multiply when the low bits of the operands are known
When the lowest bits of the operands to an integer multiply are known, the low bits of the result are deducible.
Code to deduce known-zero bottom bits already existed, but this change improves on that by deducing known-ones.
Craig Topper [Sat, 9 Dec 2017 08:19:07 +0000 (08:19 +0000)]
[X86] When inserting into the upper bits of a vXi1 vector, make sure we shift enough bits if we widened the vector.
We may need to widen the vector to make the shifts legal, but if we do that we need to make sure we shift left/right after accounting for the new size. If not we can't guarantee we are shifting in zeros.
The test cases affected actually show cases where we should move the shifts all together, but that's another problem.
Craig Topper [Sat, 9 Dec 2017 07:02:19 +0000 (07:02 +0000)]
[X86] Improve lowering of concats of mask vectors to better optimize zero vector inputs.
We were previously using kunpck with zero inputs unnecessarily. And we had cases where we would insert into a zero vector and then insert into larger zero vector incurring two sets of shifts.
The outliner previously would never outline calls. Calls are pretty common in
files, so it makes sense to outline them. In fact, in the LLVM test suite, if
you count the number of instructions that the outliner misses when you outline
calls vs when you don't, it turns out that, on average, around 6% of the
instructions encountered are calls. So, if we outline calls, we can find more
candidates, and thus save some more space.
This commit adds that functionality and updates the mir test to reflect that.
Wolfgang Pieb [Sat, 9 Dec 2017 00:39:53 +0000 (00:39 +0000)]
[NFC] Change the string offsets table tests to generate the object on the fly
which enables us to remove the test scripts and object files from the repository.
Summary:
This is LLVM instrumentation for the new HWASan tool. It is basically
a stripped down copy of ASan at this point, w/o stack or global
support. Instrumenation adds a global constructor + runtime callbacks
for every load and store.
HWASan comes with its own IR attribute.
A brief design document can be found in
clang/docs/HardwareAssistedAddressSanitizerDesign.rst (submitted earlier).
Paul Robinson [Sat, 9 Dec 2017 00:17:01 +0000 (00:17 +0000)]
Fix out-of-order stepping behavior in programs with sunk instructions.
MachineSink attempts to place instructions near the basic blocks where
they are needed. Once an instruction has been sunk, its location
relative to other instructions no longer is consistent with the
original source code. In order to ensure correct stepping in the
debugger, the debug location for sunk instructions is either merged
with the insertion point or erased if the target successor block is
empty.
Originally submitted as r318679, revised to fix sanitizer failure and
improve testing.
Craig Topper [Fri, 8 Dec 2017 23:30:03 +0000 (23:30 +0000)]
[X86][Mips] Remove unused method declaration from the X86 and Mips AsmPrinters.
Both had a declaration of EmitXRayTable, but there is no method defined in either with that name. There is a emitXRayTable in the base class with a lower case 'e' and they both call that.
Revert part of "Cleanup some GraphTraits iteration code"
This reverts part of r300656, which caused a regression in
propagateMassToSuccessors by counting edges n^2 times, where n is the
number of edges from the source basic block to the same successor basic
block. The result was both incorrect and very slow to compute for large
values of n (e.g. switches with multiple cases that go to the same basic
block).
Adrian Prantl [Fri, 8 Dec 2017 21:58:18 +0000 (21:58 +0000)]
Generalize llvm::replaceDbgDeclare and actually support the use-case that
is mentioned in the documentation (inserting a deref before the plus_uconst).
Vedant Kumar [Fri, 8 Dec 2017 21:57:28 +0000 (21:57 +0000)]
[Debugify] Add a pass to test debug info preservation
The Debugify pass synthesizes debug info for IR. It's paired with a
CheckDebugify pass which determines how much of the original debug info
is preserved. These passes make it easier to create targeted tests for
debug info preservation.
Here is the Debugify algorithm:
NextLine = 1
for (Instruction &I : M)
attach DebugLoc(NextLine++) to I
NextVar = 1
for (Instruction &I : M)
if (canAttachDebugValue(I))
attach dbg.value(NextVar++) to I
The CheckDebugify pass expects contiguous ranges of DILocations and
DILocalVariables. If it fails to find all of the expected debug info, it
prints a specific error to stderr which can be FileChecked.
This was discussed on llvm-dev in the thread:
"Passes to add/validate synthetic debug info"
Florian Hahn [Fri, 8 Dec 2017 21:49:03 +0000 (21:49 +0000)]
[CodeExtractor] Add debug locations for new call and branch instrs.
Summary:
If a partially inlined function has debug info, we have to add debug
locations to the call instruction calling the outlined function.
We use the debug location of the first instruction in the outlined
function, as the introduced call transfers control to this statement and
there is no other equivalent line in the source code.
We also use the same debug location for the branch instruction added
to jump from artificial entry block for the outlined function, which just
jumps to the first actual basic block of the outlined function.
Dan Gohman [Fri, 8 Dec 2017 21:18:21 +0000 (21:18 +0000)]
[WebAssemby] Re-apply r320041: "Support main functions with alternate signatures."
This includes a fix so that it doesn't transform declarations, and it
puts the functionality under control of a command-line option which is off
by default to avoid breaking existing setups.
Craig Topper [Fri, 8 Dec 2017 20:10:33 +0000 (20:10 +0000)]
[X86] Teach lowering to only let through (insert_subvector (vXi1 zeros), subvec, 0) for vector sizes that have native KSHIFT support.
For narrow sizes we'll widen the zero vector and widen the insert. Then do an extract_subvector to get back down to correct size.
This allows us to remove some patterns from the isel table that had to COPY_TO_REGCLASS to an oversized register, do the shift and then COPY_TO_REGCLASS back to the narrow register. Now this is represented explicitly in the DAG.
This seems to have perturbed the register allocation in one of the tests, but the number of instructions didn't change.
Shoaib Meenai [Fri, 8 Dec 2017 19:42:47 +0000 (19:42 +0000)]
[cmake] Only pass CMAKE_SYSROOT if non-empty
In my build environment (cmake 3.6.1 and gcc 4.8.5 on CentOS 7), having
an empty CMAKE_SYSROOT in the cache results in --sysroot="" being passed
to all compile commands, and then the compiler errors out because of the
empty sysroot. Only set CMAKE_SYSROOT if non-empty to avoid this.
Sanjay Patel [Fri, 8 Dec 2017 18:35:51 +0000 (18:35 +0000)]
[x86] use hasAVX2() rather than hasInt256(); NFC
These are aliases, but the thing we're checking here is that the target has
vpsllv*, not that the data type is 256-bit. Those instructions exist for
128-bit vectors too...but sadly, not for all element sizes.
Michael Trent [Fri, 8 Dec 2017 17:51:04 +0000 (17:51 +0000)]
Updated llvm-objdump to display local relocations in Mach-O binaries
Summary:
llvm-objdump's Mach-O parser was updated in r306037 to display external
relocations for MH_KEXT_BUNDLE file types. This change extends the Macho-O
parser to display local relocations for MH_PRELOAD files. When used with
the -macho option relocations will be displayed in a historical format.
Summary:
If we have the code like this:
```
float a, b;
a = std::max(a ,b);
```
it is converted into something like this:
```
%call = call dereferenceable(4) float* @_ZSt3maxIfERKT_S2_S2_(float* nonnull dereferenceable(4) %a.addr, float* nonnull dereferenceable(4) %b.addr)
%1 = bitcast float* %call to i32*
%2 = load i32, i32* %1, align 4
%3 = bitcast float* %a.addr to i32*
store i32 %2, i32* %3, align 4
```
After inlinning this code is converted to the next:
```
%1 = load float, float* %a.addr
%2 = load float, float* %b.addr
%cmp.i = fcmp fast olt float %1, %2
%__b.__a.i = select i1 %cmp.i, float* %a.addr, float* %b.addr
%3 = bitcast float* %__b.__a.i to i32*
%4 = load i32, i32* %3, align 4
%5 = bitcast float* %arrayidx to i32*
store i32 %4, i32* %5, align 4
```
This pattern is not recognized as minmax pattern.
Patch solves this problem by converting sequence
```
store (bitcast, (load bitcast (select ((cmp V1, V2), &V1, &V2))))
```
to a sequence
```
store (,load (select((cmp V1, V2), &V1, &V2)))
```
After this the code is recognized as minmax pattern.
Max Kazantsev [Fri, 8 Dec 2017 12:19:45 +0000 (12:19 +0000)]
[SCEV] Fix predicate usage in computeExitLimitFromICmp
In this method, we invoke `SimplifyICmpOperands` which takes the `Cond` predicate
by reference and may change it along with `LHS` and `RHS` SCEVs. But then we invoke
`computeShiftCompareExitLimit` with Values from which the SCEVs have been derived,
these Values have not been modified while `Cond` could be.
One of possible outcomes of this is that we may falsely prove that an infinite loop ends
within some finite number of iterations.
In this patch, we save the original `Cond` and pass it along with original operands.
This logic may be removed in future once `computeShiftCompareExitLimit` works
with SCEVs instead of value operands.
projects / llvm / log