llvm-project/llvm/test/Transforms
Sanjay Patel 5264cc772c [SimplifyCFG] limit recursion depth when speculating instructions (PR26308)
This is a fix for:
https://llvm.org/bugs/show_bug.cgi?id=26308

With the switch to using the TTI cost model in:
http://reviews.llvm.org/rL228826
...it became possible to hit a zero-cost cycle of instructions (gep -> phi -> gep...), 
so we need a cap for the recursion in DominatesMergePoint().

A recursion depth parameter was already added for a different reason in:
http://reviews.llvm.org/rL255660
...so we can just set a limit for it.

I pulled "10" out of the air and made it an independent parameter that we can play with.
It might be higher than it needs to be given the currently low default value of 
PHINodeFoldingThreshold (2). That's the starting cost value that we enter the recursion
with, and most instructions have cost set to TCC_Basic (1), so I don't think we're going
to speculate more than 2 instructions with the current parameters.

As noted in the review and the TODO comment, we can do better than just limiting recursion
depth.

Differential Revision: http://reviews.llvm.org/D16637

llvm-svn: 258971
2016-01-27 19:22:45 +00:00
..
ADCE [PM] Port ADCE to the new pass manager 2015-10-30 23:13:18 +00:00
AddDiscriminators Reimplement discriminator assignment algorithm. 2015-11-19 19:53:05 +00:00
AlignmentFromAssumptions Revert "Change memcpy/memset/memmove to have dest and source alignments." 2015-11-19 05:56:52 +00:00
ArgumentPromotion DI: Reverse direction of subprogram -> function edge. 2015-11-05 22:03:56 +00:00
AtomicExpand [IR] Add support for floating pointer atomic loads and stores 2015-12-16 00:49:36 +00:00
BBVectorize Have a single way for creating unique value names. 2015-11-22 00:16:24 +00:00
BDCE Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
BranchFolding Move branch folding test to a better location. 2015-12-03 19:41:25 +00:00
CodeExtractor Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
CodeGenPrepare [InstCombine] Rewrite bswap/bitreverse handling completely. 2016-01-15 09:20:19 +00:00
ConstProp IR: Make ConstantDataArray::getFP actually return a ConstantDataArray 2015-12-09 21:21:07 +00:00
ConstantHoisting
ConstantMerge [opaque pointer type] Add textual IR support for explicit type parameter for global aliases 2015-09-11 03:22:04 +00:00
CorrelatedValuePropagation Revert "Change memcpy/memset/memmove to have dest and source alignments." 2015-11-19 05:56:52 +00:00
CrossDSOCFI [cfi] Cross-DSO CFI diagnostic mode (LLVM part). 2016-01-25 23:35:03 +00:00
DeadArgElim [OperandBundles] Have DeadArgElim play nice with operand bundles 2015-12-23 09:58:36 +00:00
DeadStoreElimination [BasicAliasAnalysis] Take into account operand bundles in the getModRefInfo function 2016-01-16 12:15:53 +00:00
EarlyCSE Fix several accidental DOS line endings in source files 2016-01-03 17:22:03 +00:00
EliminateAvailableExternally Don't change the visibility when converting a definition to a declaration. 2015-07-13 14:18:22 +00:00
Float2Int [Float2Int] Don't operate on vector instructions 2015-12-09 21:08:18 +00:00
ForcedFunctionAttrs [attrs] Split off the forced attributes utility into its own pass that 2015-12-27 08:13:45 +00:00
FunctionAttrs [attrs] Split the late-revisit pattern for deducing norecurse in 2016-01-08 10:55:52 +00:00
FunctionImport Fix bot failure from r257493: remove extraneous temp file read 2016-01-12 17:53:59 +00:00
GCOVProfiling [GCOV] Avoid emitting profile arcs for module and skeleton CUs 2016-01-21 17:04:42 +00:00
GVN Fix for two constant propagation problems in GVN with the assume intrinsic 2016-01-21 21:32:35 +00:00
GlobalDCE [opaque pointer type] Add textual IR support for explicit type parameter for global aliases 2015-09-11 03:22:04 +00:00
GlobalOpt Make sure that any new and optimized objects created during GlobalOPT copy all the attributes from the base object. 2016-01-22 21:18:20 +00:00
IPConstantProp [SCCP] Don't violate the lattice invariants 2016-01-07 21:36:16 +00:00
IRCE
IndVarSimplify [IndVarSimplify] Rewrite loop exit values with their initial values from loop preheader 2016-01-27 07:40:41 +00:00
InferFunctionAttrs [BasicAA] Remove special casing of memset_pattern16 in favor of generic attribute inference 2016-01-06 04:53:16 +00:00
Inline [Inliner/WinEH] Honor implicit nounwinds 2016-01-20 02:15:15 +00:00
InstCombine [LibCallSimplifier] fold memset(malloc(x), 0, x) --> calloc(1, x) 2016-01-26 16:17:24 +00:00
InstMerge
InstSimplify [InstCombine] Simplify (x >> y) <= x 2016-01-21 18:55:54 +00:00
Internalize [opaque pointer type] Add textual IR support for explicit type parameter for global aliases 2015-09-11 03:22:04 +00:00
JumpThreading Add test for r257279. 2016-01-10 07:13:33 +00:00
LCSSA [WinEH] Update LCSSA to handle catchswitch with handlers inside and outside a loop 2015-12-18 18:12:35 +00:00
LICM [LICM] Fix a small oversight introduced in r256763 2016-01-04 23:16:22 +00:00
LoadCombine
LoopDeletion
LoopDistribute Allow LLE/LD and the loop versioning infrastructure to use SCEV predicates 2015-11-09 13:26:09 +00:00
LoopIdiom [LIR] Add support for structs and hand unrolled loops 2016-01-26 02:27:47 +00:00
LoopInterchange
LoopLoadElim Allow LLE/LD and the loop versioning infrastructure to use SCEV predicates 2015-11-09 13:26:09 +00:00
LoopReroll Enable loopreroll to rerool loop with pointer induction variable. 2016-01-25 19:43:45 +00:00
LoopRotate DI: Reverse direction of subprogram -> function edge. 2015-11-05 22:03:56 +00:00
LoopSimplify DI: Reverse direction of subprogram -> function edge. 2015-11-05 22:03:56 +00:00
LoopStrengthReduce Followup to 258750; update more tests to use .p2align . 2016-01-26 00:35:07 +00:00
LoopUnroll LoopUnroll: Use the optsize threshold for minsize as well 2016-01-11 22:39:43 +00:00
LoopUnswitch [IR] Reformulate LLVM's EH funclet IR 2015-12-12 05:38:55 +00:00
LoopVectorize AVX1 : Enable vector masked_load/store to AVX1. 2016-01-25 10:17:11 +00:00
LowerAtomic
LowerBitSets [cfi] Fix LowerBitSets on 32-bit targets. 2015-12-21 22:14:04 +00:00
LowerExpectIntrinsic [PM] Port StripDeadPrototypes to the new pass manager 2015-10-30 23:28:12 +00:00
LowerInvoke Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
LowerSwitch Have a single way for creating unique value names. 2015-11-22 00:16:24 +00:00
Mem2Reg [Mem2Reg] Respect optnone 2015-12-11 13:36:59 +00:00
MemCpyOpt Fix PR26051: Memcpy optimization should introduce a call to memcpy before the store destination position 2016-01-06 23:50:22 +00:00
MergeFunc [IR] Remove terminatepad 2015-12-14 18:34:23 +00:00
MetaRenamer Revert "Change memcpy/memset/memmove to have dest and source alignments." 2015-11-19 05:56:52 +00:00
NaryReassociate [NaryReassociate] allow candidate to have a different type 2015-12-18 21:36:30 +00:00
ObjCARC Add support for objc_unsafeClaimAutoreleasedReturnValue to the 2016-01-27 19:05:08 +00:00
PGOProfile [PGO] IR level instrumentation of indirect call value profiling 2016-01-21 18:11:44 +00:00
PartiallyInlineLibCalls
PhaseOrdering Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
PlaceSafepoints [PlaceSafepoints] Introduce a -spp-no-statepoints flag 2016-01-22 21:02:55 +00:00
PruneEH [PruneEH] Don't try to insert a terminator after another terminator 2016-01-23 06:00:44 +00:00
Reassociate Reassociate: Reprocess RedoInsts after each inst 2016-01-26 18:42:36 +00:00
Reg2Mem Move the personality function from LandingPadInst to Function 2015-06-17 20:52:32 +00:00
RewriteStatepointsForGC Add a "gc-transition" operand bundle 2016-01-20 19:50:25 +00:00
SCCP [opaque pointer type] Add textual IR support for explicit type parameter for global aliases 2015-09-11 03:22:04 +00:00
SLPVectorizer Reapply commit r258404 with fix 2016-01-27 13:43:27 +00:00
SROA [SROA] Also insert a bit piece expression if only one piece is needed 2016-01-14 20:06:34 +00:00
SafeStack [safestack] Add option for non-TLS unsafe stack pointer. 2015-12-22 00:13:11 +00:00
SampleProfile SamplePGO - Add initial support for inliner annotations. 2015-11-27 23:14:51 +00:00
ScalarRepl Revert "Change memcpy/memset/memmove to have dest and source alignments." 2015-11-19 05:56:52 +00:00
Scalarizer DI: Reverse direction of subprogram -> function edge. 2015-11-05 22:03:56 +00:00
SeparateConstOffsetFromGEP [SeparateConstOffsetFromGEP] sext(a)+sext(b) => sext(a+b) when a+b can't sign-overflow. 2015-08-14 02:02:05 +00:00
SimplifyCFG [SimplifyCFG] limit recursion depth when speculating instructions (PR26308) 2016-01-27 19:22:45 +00:00
Sink [IR] Reformulate LLVM's EH funclet IR 2015-12-12 05:38:55 +00:00
SpeculativeExecution
StraightLineStrengthReduce [SeparateConstOffsetFromGEP] strengthen the inbounds attribute 2015-08-13 18:48:49 +00:00
StripDeadPrototypes [PM] Port StripDeadPrototypes to the new pass manager 2015-10-30 23:28:12 +00:00
StripSymbols DI: Reverse direction of subprogram -> function edge. 2015-11-05 22:03:56 +00:00
StructurizeCFG AMDGPU: Replace some deprecated intrinsic uses in tests 2016-01-23 05:42:49 +00:00
TailCallElim Push isDereferenceableAndAlignedPointer down into isSafeToLoadUnconditionally 2016-01-17 12:35:29 +00:00
TailDup
Util [Utils] Fix incorrect dbg.declare store conversion 2016-01-14 19:12:27 +00:00