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2011-01-03Simplify GVN's value expression structure, allowing the elimination of a lot of Owen Anderson
almost-but-not-quite-identical code. No intended functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122760 91177308-0d34-0410-b5e6-96231b3b80d8
2011-01-02split dom frontier handling stuff out to its own DominanceFrontier header,Chris Lattner
so that Dominators.h is *just* domtree. Also prune #includes a bit. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122714 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21Give GVN back the ability to perform simple conditional propagation on ↵Owen Anderson
conditional branch values. I still think that LVI should be handling this, but that capability is some ways off in the future, and this matters for some significant benchmarks. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122378 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21Remove dead code.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122371 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-21GVN's Expression is not POD-like (it contains a SmallVector). Simplify code ↵Benjamin Kramer
while at it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122362 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-19tidy upChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122190 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15Preserve TBAA tags when doing load PRE.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121921 91177308-0d34-0410-b5e6-96231b3b80d8
2010-12-15Move Value::getUnderlyingObject to be a standaloneDan Gohman
function so that it can live in Analysis instead of VMCore. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121885 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30move GetPointerBaseWithConstantOffset out of GVN into ValueTracking.hChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120476 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-30remove a fixed fixmeChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120474 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-19Document the new GVN number table structure.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119865 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-18Completely rework the datastructure GVN uses to represent the value number ↵Owen Anderson
to leader mapping. Previously, this was a tree of hashtables, and a query recursed into the table for the immediate dominator ad infinitum if the initial lookup failed. This led to really bad performance on tall, narrow CFGs. We can instead replace it with what is conceptually a multimap of value numbers to leaders (actually represented by a hashtable with a list of Value*'s as the value type), and then determine which leader from that set to use very cheaply thanks to the DFS numberings maintained by DominatorTree. Because there are typically few duplicates of a given value, this scan tends to be quite fast. Additionally, we use a custom linked list and BumpPtr allocation to avoid any unnecessary allocation in representing the value-side of the multimap. This change brings with it a 15% (!) improvement in the total running time of GVN on 403.gcc, which I think is pretty good considering that includes all the "real work" being done by MemDep as well. The one downside to this approach is that we can no longer use GVN to perform simple conditional progation, but that seems like an acceptable loss since we now have LVI and CorrelatedValuePropagation to pick up the slack. If you see conditional propagation that's not happening, please file bugs against LVI or CVP. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119714 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-17Remove dead code in GVN: now that SimplifyInstruction is calledDuncan Sands
systematically, CollapsePhi will always return null here. Note that CollapsePhi did an extra check, isSafeReplacement, which the SimplifyInstruction logic does not do. I think that check was bogus - I guess we will soon find out! (It was originally added in commit 41998 without a testcase). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119456 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-14If dom tree information is available, make it possible to passDuncan Sands
it to get better phi node simplification. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119055 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-12Have GVN simplify instructions as it goes. For example, considerDuncan Sands
"%z = %x and %y". If GVN can prove that %y equals %x, then it turns this into "%z = %x and %x". With the new code, %z will be replaced with %x everywhere (and then deleted). Previously %z would be value numbered too, which is a waste of time. Also, while a clever value numbering algorithm would give %z the same value number as %x, our current one doesn't do so (at least I don't think it does). The new logic has an essentially equivalent effect to what you would get if %z was given the same value number as %x, i.e. it should make value numbering smarter. While there, get hold of target data once at the start rather than a gazillion times all over the place. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118923 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-11Add helper functions for computing the Location of load, store,Dan Gohman
and vaarg instructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118845 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10Enhance GVN to do more precise alias queries for non-local memoryDan Gohman
references. For example, this allows gvn to eliminate the load in this example: void foo(int n, int* p, int *q) { p[0] = 0; p[1] = 1; if (n) { *q = p[0]; } } git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118714 91177308-0d34-0410-b5e6-96231b3b80d8
2010-11-10Use getValueOperand() and getPointerOperand() on load and storeDan Gohman
instructions instead of hard-coding operand numbers. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@118698 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-19Get rid of static constructors for pass registration. Instead, every pass ↵Owen Anderson
exposes an initializeMyPassFunction(), which must be called in the pass's constructor. This function uses static dependency declarations to recursively initialize the pass's dependencies. Clients that only create passes through the createFooPass() APIs will require no changes. Clients that want to use the CommandLine options for passes will need to manually call the appropriate initialization functions in PassInitialization.h before parsing commandline arguments. I have tested this with all standard configurations of clang and llvm-gcc on Darwin. It is possible that there are problems with the static dependencies that will only be visible with non-standard options. If you encounter any crash in pass registration/creation, please send the testcase to me directly. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116820 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-12Begin adding static dependence information to passes, which will allow us toOwen Anderson
perform initialization without static constructors AND without explicit initialization by the client. For the moment, passes are required to initialize both their (potential) dependencies and any passes they preserve. I hope to be able to relax the latter requirement in the future. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@116334 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-07Now with fewer extraneous semicolons!Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115996 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-01Now that the profitable bits of EnableFullLoadPRE have been enabled by ↵Owen Anderson
default, rip out the remainder. Anyone interested in more general PRE would be better served by implementing it separately, to get real anticipation calculation, etc. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115337 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-30We do want to allow LoadPRE to perform LICM-like transformations: we already ↵Owen Anderson
consider PHI nodes to be negligible for code size (making this transform code size neutral), and it allows us to hoist values out of loops, which is always a good thing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115205 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-25LoadPRE was not properly checking that the load it was PRE'ing ↵Owen Anderson
post-dominated the block it was being hoisted to. Splitting critical edges at the merge point only addressed part of the issue; it is also possible for non-post-domination to occur when the path from the load to the merge has branches in it. Unfortunately, full anticipation analysis is time-consuming, so for now approximate it. This is strictly more conservative than real anticipation, so we will miss some cases that real PRE would allow, but we also no longer insert loads into paths where they didn't exist before. :-) This is a very slight net positive on SPEC for me (0.5% on average). Most of the benchmarks are largely unaffected, but when it pays off it pays off decently: 181.mcf improves by 4.5% on my machine. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@114785 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-04zap dead code.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113073 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-02Reapply commit 112699, speculatively reverted by echristo, sinceDuncan Sands
I'm sure it is harmless. Original commit message: If PrototypeValue is erased in the middle of using the SSAUpdator then the SSAUpdator may access freed memory. Instead, simply pass in the type and name explicitly, which is all that was used anyway. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112810 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01Speculatively revert 112699 and 112702, they seem to be causingEric Christopher
self host errors on clang-x86-64. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112719 91177308-0d34-0410-b5e6-96231b3b80d8
2010-09-01If PrototypeValue is erased in the middle of using the SSAUpdatorDuncan Sands
then the SSAUpdator may access freed memory. Instead, simply pass in the type and name explicitly, which is all that was used anyway. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112699 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-29remove dead protoChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@112408 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-07Don't attempt the PRE inline asm calls, since we don't value number them ↵Owen Anderson
yet. Fixes PR7835. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110489 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06Reapply r110396, with fixes to appease the Linux buildbot gods.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110460 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-06Revert r110396 to fix buildbots.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110410 91177308-0d34-0410-b5e6-96231b3b80d8
2010-08-05Don't use PassInfo* as a type identifier for passes. Instead, use the ↵Owen Anderson
address of the static ID member as the sole unique type identifier. Clean up APIs related to this change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@110396 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-22mass elimination of reliance on automatic iterator dereferencingGabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109103 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-21Fix batch of converting RegisterPass<> to INTIALIZE_PASS().Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@109045 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-09cache result of operator* (found by inspection)Gabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107971 91177308-0d34-0410-b5e6-96231b3b80d8
2010-07-09cache result of operator*Gabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107969 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-30use getNumArgOperands instead of getNumOperandsGabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@107272 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24use ArgOperand APIGabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106730 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-24use callsite to obtain all argumentsGabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106729 91177308-0d34-0410-b5e6-96231b3b80d8
2010-06-22Use pre-increment instead of post-increment when the result is not used.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@106542 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-28Move FindAvailableLoadedValue isSafeToLoadUnconditionally out ofDan Gohman
lib/Transforms/Utils and into lib/Analysis so that Analysis passes can use them. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@104949 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-08Fix PR7052, patch by Jakub Staszak!Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103347 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-05Use the right version of "append" to combine two SmallVectors.Bob Wilson
This fixes the compile-time regressions seen in last night's tests. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103118 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-04Defer adding critical edges to the "toSplit" list until after checking forBob Wilson
indirect branches in all the predecessors. This avoids unnecessarily splitting edges in cases where load PRE is not possible anyway. Thanks to Jakub Staszak for pointing this out. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103034 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16Revert 101465, it broke internal OpenGL testing.Eric Christopher
Probably the best way to know that all getOperand() calls have been handled is to replace that API instead of updating. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101579 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16reapply r101434Gabor Greif
with a fix for self-hosting rotate CallInst operands, i.e. move callee to the back of the operand array the motivation for this patch are laid out in my mail to llvm-commits: more efficient access to operands and callee, faster callgraph-construction, smaller compiler binary git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101465 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-16back out r101423 and r101397, they break llvm-gcc self-host on darwin10Gabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101434 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15reapply r101364, which has been backed out in r101368Gabor Greif
with a fix rotate CallInst operands, i.e. move callee to the back of the operand array the motivation for this patch are laid out in my mail to llvm-commits: more efficient access to operands and callee, faster callgraph-construction, smaller compiler binary git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101397 91177308-0d34-0410-b5e6-96231b3b80d8
2010-04-15Fix a bunch of namespace polution.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101376 91177308-0d34-0410-b5e6-96231b3b80d8