Summary:
I have been getting rather difficult to reproduce SIGBUS crashes when
compiling certain FreeBSD sources, and their stack traces pointed
squarely at `SelectionDAG::salvageDebugInfo()`:
```
Core was generated by `/usr/obj/share/dim/src/freebsd/clang600-import/amd64.amd64/tmp/usr/bin/cc -cc1 -'.
Program terminated with signal SIGBUS, Bus error.
#0 isInvalidated () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h:115
115 bool isInvalidated() const { return Invalid; }
(gdb) bt
#0 isInvalidated () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SDNodeDbgValue.h:115
#1 salvageDebugInfo () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:7116
#2 0x00000000033b2516 in operator() () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3595
#3 __invoke<(lambda at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3593:59) &, llvm::SDNode *, llvm::SDNode *> () at /usr/include/c++/v1/type_traits:4323
#4 __call<(lambda at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3593:59) &, llvm::SDNode *, llvm::SDNode *> () at /usr/include/c++/v1/__functional_base:349
#5 operator() () at /usr/include/c++/v1/functional:1562
#6 0x00000000033b0817 in operator() () at /usr/include/c++/v1/functional:1916
#7 NodeDeleted () at /share/dim/src/freebsd/clang600-import/contrib/llvm/include/llvm/CodeGen/SelectionDAG.h:293
#8 0x0000000003529dde in RemoveDeadNodes () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:610
#9 0x00000000035556df in MorphNodeTo () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:6794
#10 0x00000000033a9acc in MorphNode () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:2594
#11 0x00000000033ac80b in SelectCodeCommon () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:3601
#12 0x00000000023d464b in SelectCode () at /usr/obj/share/dim/src/freebsd/clang600-import/amd64.amd64/tmp/obj-tools/lib/clang/libllvm/X86GenDAGISel.inc:282902
#13 Select () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp:3072
#14 0x00000000033a5afa in DoInstructionSelection () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:988
#15 0x00000000033a4e1a in CodeGenAndEmitDAG () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:868
#16 0x00000000033a2643 in SelectAllBasicBlocks () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:1624
#17 0x000000000339f158 in runOnMachineFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp:466
#18 0x00000000023d03c4 in runOnMachineFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/Target/X86/X86ISelDAGToDAG.cpp:175
#19 0x00000000035cc8c2 in runOnFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/MachineFunctionPass.cpp:62
#20 0x00000000030dca9a in runOnFunction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1520
#21 0x00000000030dccf3 in runOnModule () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1541
#22 0x00000000030dd228 in runOnModule () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1597
#23 run () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/IR/LegacyPassManager.cpp:1700
#24 0x00000000014db578 in EmitAssembly () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp:815
#25 EmitBackendOutput () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/CodeGen/BackendUtil.cpp:1181
#26 0x00000000014d5b26 in HandleTranslationUnit () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/CodeGen/CodeGenAction.cpp:292
#27 0x0000000001c4c332 in ParseAST () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/Parse/ParseAST.cpp:159
#28 0x00000000015d546c in Execute () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/Frontend/FrontendAction.cpp:897
#29 0x0000000001cec311 in ExecuteAction () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/Frontend/CompilerInstance.cpp:991
#30 0x00000000014b4f81 in ExecuteCompilerInvocation () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/lib/FrontendTool/ExecuteCompilerInvocation.cpp:252
#31 0x00000000014aa73f in cc1_main () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/tools/driver/cc1_main.cpp:221
#32 0x00000000014b2928 in ExecuteCC1Tool () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/tools/driver/driver.cpp:309
#33 main () at /share/dim/src/freebsd/clang600-import/contrib/llvm/tools/clang/tools/driver/driver.cpp:388
(gdb) frame 1
#1 salvageDebugInfo () at /share/dim/src/freebsd/clang600-import/contrib/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:7116
7116 if (DV->isInvalidated())
(gdb) disassemble
Dump of assembler code for function salvageDebugInfo():
[...]
0x0000000003557348 <+744>: nopl 0x0(%rax,%rax,1)
0x0000000003557350 <+752>: mov (%r12),%r13
=> 0x0000000003557354 <+756>: cmpb $0x0,0x31(%r13)
0x0000000003557359 <+761>: jne 0x35573b0 <salvageDebugInfo()+848>
(gdb) info registers
[...]
r13 0x5a5a5a5a5a5a5a5a 6510615555426900570
```
The `0x5a5a5a5a5a5a5a5a` value in `r13` indicates the memory was either
uninitialized, or already freed.
Unfortunately I do not have a simple self-contained test case for this.
However, it seems pretty clear that the call to `AddDbgValue()` in
`salvageDebugInfo()` causes the problems, since it modifies
`SelectionDag::DbgInfo` while looping through one of its DenseMaps:
```
void SelectionDAG::salvageDebugInfo(SDNode &N) {
[...]
for (auto DV : GetDbgValues(&N)) {
if (DV->isInvalidated())
continue;
[...]
AddDbgValue(Clone, N0.getNode(), false);
[...]
}
}
```
At least, if I comment out the `AddDbgValue()` call, the crashes go
away. I propose to change this function slightly, similar to the
`SelectionDAG::transferDbgValues()` function just above it, to save the
cloned SDDbgValues in a separate SmallVector, and only call
AddDbgValue() on them after the for loop is done.
Reviewers: aprantl, bogner, bkramer, davide
Reviewed By: davide
Subscribers: davide, krytarowski, JDevlieghere, emaste, llvm-commits
Differential Revision: https://reviews.llvm.org/D41589
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321545 91177308-0d34-0410-b5e6-96231b3b80d8
For example, float operations may fail to constant fold under certain circumstances (inf/nan/denormal creation etc.)
Reduced from oss-fuzz #4802 test case
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321488 91177308-0d34-0410-b5e6-96231b3b80d8
This moves the combine for turning ANDs into shuffle with zero out of SimplifyVBinOps and places it only in visitAND below the reassociate handling. This fixes the specific case I noticed where we failed to combine two ands with constants.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321417 91177308-0d34-0410-b5e6-96231b3b80d8
getOperand returns an SDValue that contains the node and the result number. There is no guarantee that the result number if 0. By using the -> operator we are calling SDNode::getValueType rather than SDValue::getValueType. This requires supplying a result number and we shouldn't assume it was 0.
I don't have a test case. Just noticed while cleaning up some other code and saw that it occurred in other places.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321397 91177308-0d34-0410-b5e6-96231b3b80d8
BaseIndexOffset supercedes findBaseOffset analysis save only Constant
Pool addresses. Migrate analysis to BaseIndexOffset.
Relanding after correcting base address matching check.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321389 91177308-0d34-0410-b5e6-96231b3b80d8
which was causing miscompilations in for some test-suite components.
This reverts commit 3e9de9ff0f3162920a2a3cba51c7dc14b54b4d16.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321380 91177308-0d34-0410-b5e6-96231b3b80d8
Re-land r321234. It had to be reverted because it broke the shared
library build. The shared library build broke because there was a
missing LLVMBuild dependency from lib/Passes (which calls
TargetMachine::getTargetIRAnalysis) to lib/Target. As far as I can
tell, this problem was always there but was somehow masked
before (perhaps because TargetMachine::getTargetIRAnalysis was a
virtual function).
Original commit message:
This makes the TargetMachine interface a bit simpler. We still need
the std::function in TargetIRAnalysis to avoid having to add a
dependency from Analysis to Target.
See discussion:
http://lists.llvm.org/pipermail/llvm-dev/2017-December/119749.html
I avoided adding all of the backend owners to this review since the
change is simple, but let me know if you feel differently about this.
Reviewers: echristo, MatzeB, hfinkel
Reviewed By: hfinkel
Subscribers: jholewinski, jfb, arsenm, dschuff, mcrosier, sdardis, nemanjai, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, llvm-commits
Differential Revision: https://reviews.llvm.org/D41464
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321375 91177308-0d34-0410-b5e6-96231b3b80d8
This seems to improve X86's ability to match this into an address computation. Otherwise the other operand gets assigned to the base register and the stack pointer + frame index ends up in the index register. But index registers can't encode ESP/RSP so we end up having to move it into another register to meet the constraint.
I could try to improve the address matcher in X86, but swapping the producer seemed easier. Several other places already have the operands in this order so this is at least consistent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321370 91177308-0d34-0410-b5e6-96231b3b80d8
BaseIndexOffset supercedes findBaseOffset analysis save only Constant
Pool addresses. Migrate analysis to BaseIndexOffset.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321364 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This replaces calls to getEntryCount().hasValue() with hasProfileData
that does the same thing. This refactoring is useful to do before adding
synthetic function entry counts but also a useful cleanup IMO even
otherwise. I have used hasProfileData instead of hasRealProfileData as
David had earlier suggested since I think profile implies "real" and I
use the phrase "synthetic entry count" and not "synthetic profile count"
but I am fine calling it hasRealProfileData if you prefer.
Reviewers: davidxl, silvas
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41461
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321331 91177308-0d34-0410-b5e6-96231b3b80d8
More general cases are already handled by constant canonicalization and then the ReassociateOps call at line 5327
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321280 91177308-0d34-0410-b5e6-96231b3b80d8
The knownbits_mask_or_shuffle_uitofp change is interesting - shuffle combines manage to kick in, removing the AND constant mask load. For targets with fast-variable-shuffle this should reduce further to VPOR+VPSHUFB+VCVTDQ2PS.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321279 91177308-0d34-0410-b5e6-96231b3b80d8
If the SRL node is only used by an AND, we may be able to set the
ExtVT to the width of the mask, making the AND redundant. To support
this, another check has been added in isLegalNarrowLoad which queries
whether the load is valid.
Differential Revision: https://reviews.llvm.org/D41350
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321259 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
This makes the TargetMachine interface a bit simpler. We still need
the std::function in TargetIRAnalysis to avoid having to add a
dependency from Analysis to Target.
See discussion:
http://lists.llvm.org/pipermail/llvm-dev/2017-December/119749.html
I avoided adding all of the backend owners to this review since the
change is simple, but let me know if you feel differently about this.
Reviewers: echristo, MatzeB, hfinkel
Reviewed By: hfinkel
Subscribers: jholewinski, jfb, arsenm, dschuff, mcrosier, sdardis, nemanjai, nhaehnle, javed.absar, sbc100, jgravelle-google, aheejin, kbarton, llvm-commits
Differential Revision: https://reviews.llvm.org/D41464
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321234 91177308-0d34-0410-b5e6-96231b3b80d8
When intrinsics are allowed to have mem operands, there
are two ways this can happen. First is an intrinsic
that is marked has having a mem operand, but is not handled
by getTgtMemIntrinsic.
The second way can occur even for intrinsics which do not
have a mem operand. It seems the selector table does
some kind of sorting based on the opcode, and the
mem ref recording can happen in the same scope for
intrinsics that both do and do not have mem refs.
I haven't been able to figure out exactly why this happens
(although it happens even with the matcher optimizations disabled).
I'm not sure if it's worth trying to avoid hitting this for
these nodes since I think it's still reasonable to handle
this in case getTgtMemIntrinic is not implemented.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321208 91177308-0d34-0410-b5e6-96231b3b80d8
Prevent overlapping store elision when overlapping store is
pre-inc/dec as analysis is wrong in these cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321204 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
The function section prefix for PGO based layout (e.g. hot/unlikely)
should look at the hotness of all blocks not just the entry BB.
A function with a cold entry but a very hot loop should be placed in the
hot section, for example, so that it is located close to other hot
functions it may call. For SamplePGO it was already looking at the
branch weights on calls, and I made that code conditional on whether
this is SamplePGO since it was essentially a noop for instrumentation
PGO anyway.
Reviewers: davidxl
Subscribers: eraman, llvm-commits
Differential Revision: https://reviews.llvm.org/D41395
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321197 91177308-0d34-0410-b5e6-96231b3b80d8
These functions simply call their counterparts in the associated SDNode,
which do take an optional SelectionDAG. This change makes the legalization
debug trace a little easier to read, since target-specific nodes will
now have their names shown instead of "Unknown node #123".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321180 91177308-0d34-0410-b5e6-96231b3b80d8
Work towards the unification of MIR and debug output by refactoring the
interfaces.
Also add support for printing with a null TargetIntrinsicInfo and no
MachineFunction.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321111 91177308-0d34-0410-b5e6-96231b3b80d8
Another followup to my refactoring in r321036: Turns out we can end up
with an x86 darwin target that is not macos (simulator triples can look
like i386-apple-ios) so we need the x86/32bit check in all cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321104 91177308-0d34-0410-b5e6-96231b3b80d8
This doesn't add legalizer support, just prevents crashing so that we
can gracefully fall back to SDAG.
Fixes PR35690.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321091 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Extend overlapping store elision to handle overwrites of stores by
larger stores.
Nontemporal tests have been modified to add memory dependencies to
prevent store elision.
Reviewers: craig.topper, rnk, t.p.northover
Subscribers: javed.absar, hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D40969
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321089 91177308-0d34-0410-b5e6-96231b3b80d8
Work towards the unification of MIR and debug output by refactoring the
interfaces.
Before this patch we printed "<call frame instruction>" in the debug
output.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321084 91177308-0d34-0410-b5e6-96231b3b80d8
I missed some prefixes and the fact that on AArch64 we use "bzero"
instead of "__bzero" as on X86 when doing my refactoring in r321035.
Improve tests for bzero.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321046 91177308-0d34-0410-b5e6-96231b3b80d8
I missed the fact that the later called InitLibcallCallingConvs()
overrides some things set in InitLibcalls() when I did the refactoring
in r321036.
Fix by merging InitLibcallCallingConvs() into InitLibcalls() and doing
the initialization earlier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321045 91177308-0d34-0410-b5e6-96231b3b80d8
WatchOS isn't report as iOS (as opposed to tvos) so the exception I
added in my last commit wasn't necessary after all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321041 91177308-0d34-0410-b5e6-96231b3b80d8
Note:
- X86ISelLowering: setLibcallName(SINCOS) was superfluous as
InitLibcalls() already does it.
- ARMISelLowering: Setting libcallnames for sincos/sincosf seemed
superfluous as in the darwin case it wouldn't be used while for all
other cases InitLibcalls already does it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321036 91177308-0d34-0410-b5e6-96231b3b80d8
Search from AND nodes to find whether they can be propagated back to
loads, so that the AND and load can be combined into a narrow load.
We search through OR, XOR and other AND nodes and all bar one of the
leaves are required to be loads or constants. The exception node then
needs to be masked off meaning that the 'and' isn't removed, but the
loads(s) are narrowed still.
Differential Revision: https://reviews.llvm.org/D41177
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320962 91177308-0d34-0410-b5e6-96231b3b80d8
When we put the value in select placeholder we must pass
the value through simplification tracker due to the value might
be already simplified and erased.
This is a fix for PR35658.
Reviewers: john.brawn, uabelho
Reviewed By: john.brawn
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D41251
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@320956 91177308-0d34-0410-b5e6-96231b3b80d8