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* Fix broken CHECK lines.Benjamin Kramer2014-01-11
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@199016 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix "existant" typosAlp Toker2013-10-29
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193579 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix SCEVExpander: don't try to expand quadratic recurrences outside a loop.Andrew Trick2013-10-25
| | | | | | | | | | | | Partial fix for PR17459: wrong code at -O3 on x86_64-linux-gnu (affecting trunk and 3.3) When SCEV expands a recurrence outside of a loop it attempts to scale by the stride of the recurrence. Chained recurrences don't work that way. We could compute binomial coefficients, but would hve to guarantee that the chained AddRec's are in a perfectly reduced form. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193438 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix LSR: don't normalize quadratic recurrences.Andrew Trick2013-10-25
| | | | | | | | | | Partial fix for PR17459: wrong code at -O3 on x86_64-linux-gnu (affecting trunk and 3.3) ScalarEvolutionNormalization was attempting to normalize by adding and subtracting strides. Chained recurrences don't work that way. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193437 91177308-0d34-0410-b5e6-96231b3b80d8
* SCEVExpander: Fix a regression I introduced by to eagerly adding RAII objects.Benjamin Kramer2013-10-01
| | | | | | PR17425. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@191741 91177308-0d34-0410-b5e6-96231b3b80d8
* Teach loop-idiom about address space pointer sizesMatt Arsenault2013-09-11
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@190491 91177308-0d34-0410-b5e6-96231b3b80d8
* [tests] Cleanup initialization of test suffixes.Daniel Dunbar2013-08-16
| | | | | | | | | | | | | | | | | - Instead of setting the suffixes in a bunch of places, just set one master list in the top-level config. We now only modify the suffix list in a few suites that have one particular unique suffix (.ml, .mc, .yaml, .td, .py). - Aside from removing the need for a bunch of lit.local.cfg files, this enables 4 tests that were inadvertently being skipped (one in Transforms/BranchFolding, a .s file each in DebugInfo/AArch64 and CodeGen/PowerPC, and one in CodeGen/SI which is now failing and has been XFAILED). - This commit also fixes a bunch of config files to use config.root instead of older copy-pasted code. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188513 91177308-0d34-0410-b5e6-96231b3b80d8
* Allocate local registers in order for optimal coloring.Andrew Trick2013-07-25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Also avoid locals evicting locals just because they want a cheaper register. Problem: MI Sched knows exactly how many registers we have and assumes they can be colored. In cases where we have large blocks, usually from unrolled loops, greedy coloring fails. This is a source of "regressions" from the MI Scheduler on x86. I noticed this issue on x86 where we have long chains of two-address defs in the same live range. It's easy to see this in matrix multiplication benchmarks like IRSmk and even the unit test misched-matmul.ll. A fundamental difference between the LLVM register allocator and conventional graph coloring is that in our model a live range can't discover its neighbors, it can only verify its neighbors. That's why we initially went for greedy coloring and added eviction to deal with the hard cases. However, for singly defined and two-address live ranges, we can optimally color without visiting neighbors simply by processing the live ranges in instruction order. Other beneficial side effects: It is much easier to understand and debug regalloc for large blocks when the live ranges are allocated in order. Yes, global allocation is still very confusing, but it's nice to be able to comprehend what happened locally. Heuristics could be added to bias register assignment based on instruction locality (think late register pairing, banks...). Intuituvely this will make some test cases that are on the threshold of register pressure more stable. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@187139 91177308-0d34-0410-b5e6-96231b3b80d8
* Catch more CHECK that can be converted to CHECK-LABEL in Transforms for ↵Stephen Lin2013-07-14
| | | | | | | | | | | | | | | | | | | | | | | easier debugging. No functionality change. This conversion was done with the following bash script: find test/Transforms -name "*.ll" | \ while read NAME; do echo "$NAME" if ! grep -q "^; *RUN: *llc" $NAME; then TEMP=`mktemp -t temp` cp $NAME $TEMP sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \ while read FUNC; do sed -i '' "s/;\(.*\)\([A-Za-z0-9_]*\):\( *\)define\([^@]*\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3define\4@$FUNC(/g" $TEMP done mv $TEMP $NAME fi done git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186269 91177308-0d34-0410-b5e6-96231b3b80d8
* Update Transforms tests to use CHECK-LABEL for easier debugging. No ↵Stephen Lin2013-07-14
| | | | | | | | | | | | | | | | | | | | | | | functionality change. This update was done with the following bash script: find test/Transforms -name "*.ll" | \ while read NAME; do echo "$NAME" if ! grep -q "^; *RUN: *llc" $NAME; then TEMP=`mktemp -t temp` cp $NAME $TEMP sed -n "s/^define [^@]*@\([A-Za-z0-9_]*\)(.*$/\1/p" < $NAME | \ while read FUNC; do sed -i '' "s/;\(.*\)\([A-Za-z0-9_]*\):\( *\)@$FUNC\([( ]*\)\$/;\1\2-LABEL:\3@$FUNC(/g" $TEMP done mv $TEMP $NAME fi done git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186268 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR: Fix the parameters used to compute the scaling factor cost.Quentin Colombet2013-06-19
| | | | | | | | | | | | | | Prior to this change, the considered addressing modes may be invalid since the maximum and minimum offsets were not taking into account. This was causing an assertion failure. The added test case exercices that behavior. <rdar://problem/14199725> Assertion failed: (CurScaleCost >= 0 && "Legal addressing mode has an illegal cost!") git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@184341 91177308-0d34-0410-b5e6-96231b3b80d8
* Modify how the formulae are rated in Loop Strength Reduce.Quentin Colombet2013-05-31
| | | | | | | | | | | | | | | Namely, check if the target allows to fold more that one register in the addressing mode and if yes, adjust the cost accordingly. Prior to this commit, reg1 + scale * reg2 accesses were artificially preferred to reg1 + reg2 accesses. Indeed, the cost model wrongly assumed that reg1 + reg2 needs a temporary register for the computation, whereas it was correctly estimated for reg1 + scale * reg2. <rdar://problem/13973908> git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@183021 91177308-0d34-0410-b5e6-96231b3b80d8
* Track IR ordering of SelectionDAG nodes 3/4.Andrew Trick2013-05-25
| | | | | | | Remove the old IR ordering mechanism and switch to new one. Fix unit test failures. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182704 91177308-0d34-0410-b5e6-96231b3b80d8
* TBAA: remove !tbaa from testing cases if not used.Manman Ren2013-05-02
| | | | | | | | This will make it easier to turn on struct-path aware TBAA since the metadata format will change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180935 91177308-0d34-0410-b5e6-96231b3b80d8
* TBAA: remove !tbaa from testing cases if not used.Manman Ren2013-04-30
| | | | | | | | This will make it easier to turn on struct-path aware TBAA since the metadata format will change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@180796 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR IVChain improvement.Andrew Trick2013-02-09
| | | | | | | | | Handle chains in which the same offset is used for both loads and stores to the same array. Fixes rdar://11410078. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174789 91177308-0d34-0410-b5e6-96231b3b80d8
* Remove target triple from an LSR test.Andrew Trick2013-01-22
| | | | | | Manish already fixed this test to work with NoTTI. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173110 91177308-0d34-0410-b5e6-96231b3b80d8
* Remove triple from this test, it makes it fail when X86 TTI is missing.Benjamin Kramer2013-01-16
| | | | | | Without a triple opt falls back to NoTTI which comes closer to LSR's pre-TTI behavior. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172609 91177308-0d34-0410-b5e6-96231b3b80d8
* Pattern-matched variables in post-inc-icmpzero.llRenato Golin2013-01-15
| | | | | | | | | | | Test was failing for clang-native-arm-cortex-a9 build-bot configuration. The reason for the failure was the test was using hardcoded names. The attached patch fixes this failure by replacing the hard-coded variables names with pattern-matched variable names. Patch by Manish Verma, ARM git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172534 91177308-0d34-0410-b5e6-96231b3b80d8
* SCEVExpander fix. RAUW needs to update the InsertedExpressions cache.Andrew Trick2013-01-14
| | | | | | | | Note that this bug is only exposed because LTO fails to use TTI. Fixes self-LTO of clang. rdar://13007381. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@172462 91177308-0d34-0410-b5e6-96231b3b80d8
* Switch the SCEV expander and LoopStrengthReduce to useChandler Carruth2013-01-07
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TargetTransformInfo rather than TargetLowering, removing one of the primary instances of the layering violation of Transforms depending directly on Target. This is a really big deal because LSR used to be a "special" pass that could only be tested fully using llc and by looking at the full output of it. It also couldn't run with any other loop passes because it had to be created by the backend. No longer is this true. LSR is now just a normal pass and we should probably lift the creation of LSR out of lib/CodeGen/Passes.cpp and into the PassManagerBuilder. =] I've not done this, or updated all of the tests to use opt and a triple, because I suspect someone more familiar with LSR would do a better job. This change should be essentially without functional impact for normal compilations, and only change behvaior of targetless compilations. The conversion required changing all of the LSR code to refer to the TTI interfaces, which fortunately are very similar to TargetLowering's interfaces. However, it also allowed us to *always* expect to have some implementation around. I've pushed that simplification through the pass, and leveraged it to simplify code somewhat. It required some test updates for one of two things: either we used to skip some checks altogether but now we get the default "no" answer for them, or we used to have no information about the target and now we do have some. I've also started the process of removing AddrMode, as the TTI interface doesn't use it any longer. In some cases this simplifies code, and in others it adds some complexity, but I think it's not a bad tradeoff even there. Subsequent patches will try to clean this up even further and use other (more appropriate) abstractions. Yet again, almost all of the formatting changes brought to you by clang-format. =] git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171735 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix a crash in LSR replaceCongruentIVs.Andrew Trick2013-01-06
| | | | | | | Indirect branch in the preheader crashes replaceCongruentIVs. Fixes rdar://12910141. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171653 91177308-0d34-0410-b5e6-96231b3b80d8
* Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ↵Dmitri Gribenko2012-12-30
| | | | | | | | | ModuleID This is done to avoid odd test failures, like the one fixed in r171243. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171250 91177308-0d34-0410-b5e6-96231b3b80d8
* Tests: rewrite 'opt ... %s' to 'opt ... < %s' so that opt does not emit a ↵Dmitri Gribenko2012-12-30
| | | | | | | | | ModuleID This is done to avoid odd test failures, like the one fixed in r171243. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@171246 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR critical edge splitting fix for PR13756.Andrew Trick2012-09-18
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@164147 91177308-0d34-0410-b5e6-96231b3b80d8
* During the CodeGenPrepare we often lower intrinsics (such as objsize)Nadav Rotem2012-08-14
| | | | | | | | | | | | | and allow some optimizations to turn conditional branches into unconditional. This commit adds a simple control-flow optimization which merges two consecutive basic blocks which are connected by a single edge. This allows the codegen to operate on larger basic blocks. rdar://11973998 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161852 91177308-0d34-0410-b5e6-96231b3b80d8
* Add a much more conservative strategy for aligning branch targets.Chandler Carruth2012-08-07
| | | | | | | | | | | | | Previously, MBP essentially aligned every branch target it could. This bloats code quite a bit, especially non-looping code which has no real reason to prefer aligned branch targets so heavily. As Andy said in review, it's still a bit odd to do this without a real cost model, but this at least has much more plausible heuristics. Fixes PR13265. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161409 91177308-0d34-0410-b5e6-96231b3b80d8
* Added unit test for PR13361: LSR + SCEV "hangs" on reasonably sized test.Andrew Trick2012-07-18
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160439 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR Fix: check SCEV expression safety before expansion.Andrew Trick2012-07-13
| | | | | | | | | | All SCEV expressions used by LSR formulae must be safe to expand. i.e. they may not contain UDiv unless we can prove nonzero denominator. Fixes PR11356: LSR hoists UDiv. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160205 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix the remaining TCL-style quotes found in the testsuite. This isChandler Carruth2012-07-02
| | | | | | | | | | | | | | | | | another mechanical change accomplished though the power of terrible Perl scripts. I have manually switched some "s to 's to make escaping simpler. While I started this to fix tests that aren't run in all configurations, the massive number of tests is due to a really frustrating fragility of our testing infrastructure: things like 'grep -v', 'not grep', and 'expected failures' can mask broken tests all too easily. Essentially, I'm deeply disturbed that I can change the testsuite so radically without causing any change in results for most platforms. =/ git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159547 91177308-0d34-0410-b5e6-96231b3b80d8
* Convert all tests using TCL-style quoting to use shell-style quoting.Chandler Carruth2012-07-02
| | | | | | | | | | | | | | | | | | | | | | | | This was done through the aid of a terrible Perl creation. I will not paste any of the horrors here. Suffice to say, it require multiple staged rounds of replacements, state carried between, and a few nested-construct-parsing hacks that I'm not proud of. It happens, by luck, to be able to deal with all the TCL-quoting patterns in evidence in the LLVM test suite. If anyone is maintaining large out-of-tree test trees, feel free to poke me and I'll send you the steps I used to convert things, as well as answer any painful questions etc. IRC works best for this type of thing I find. Once converted, switch the LLVM lit config to use ShTests the same as Clang. In addition to being able to delete large amounts of Python code from 'lit', this will also simplify the entire test suite and some of lit's architecture. Finally, the test suite runs 33% faster on Linux now. ;] For my 16-hardware-thread (2x 4-core xeon e5520): 36s -> 24s git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@159525 91177308-0d34-0410-b5e6-96231b3b80d8
* Unit test for LSR kind=Special fix: r158536.Andrew Trick2012-06-15
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@158570 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR fix: add a missing phi check during IV hoisting.Andrew Trick2012-05-22
| | | | | | Fixes PR12898: SCEVExpander crash. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@157263 91177308-0d34-0410-b5e6-96231b3b80d8
* Make sure HoistInsertPosition finds a position that is dominated by allRafael Espindola2012-04-30
| | | | | | inputs. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155809 91177308-0d34-0410-b5e6-96231b3b80d8
* Flip the new block-placement pass to be on by default.Chandler Carruth2012-04-16
| | | | | | | | | | | | | | | | | | | | | | | | | | This is mostly to test the waters. I'd like to get results from FNT build bots and other bots running on non-x86 platforms. This feature has been pretty heavily tested over the last few months by me, and it fixes several of the execution time regressions caused by the inlining work by preventing inlining decisions from radically impacting block layout. I've seen very large improvements in yacr2 and ackermann benchmarks, along with the expected noise across all of the benchmark suite whenever code layout changes. I've analyzed all of the regressions and fixed them, or found them to be impossible to fix. See my email to llvmdev for more details. I'd like for this to be in 3.1 as it complements the inliner changes, but if any failures are showing up or anyone has concerns, it is just a flag flip and so can be easily turned off. I'm switching it on tonight to try and get at least one run through various folks' performance suites in case SPEC or something else has serious issues with it. I'll watch bots and revert if anything shows up. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@154816 91177308-0d34-0410-b5e6-96231b3b80d8
* Unit test for PR11950: LSR crash.Andrew Trick2012-03-26
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153472 91177308-0d34-0410-b5e6-96231b3b80d8
* Continue cleanup of LIT, getting rid of the remaining artifacts from dejagnuEli Bendersky2012-03-25
| | | | | | | | | | | | | | | | | | * Removed test/lib/llvm.exp - it is no longer needed * Deleted the dg.exp reading code from test/lit.cfg. There are no dg.exp files left in the test suite so this code is no longer required. test/lit.cfg is now much shorter and clearer * Removed a lot of duplicate code in lit.local.cfg files that need access to the root configuration, by adding a "root" attribute to the TestingConfig object. This attribute is dynamically computed to provide the same information as was previously provided by the custom getRoot functions. * Documented the config.root attribute in docs/CommandGuide/lit.pod git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153408 91177308-0d34-0410-b5e6-96231b3b80d8
* Convert -indvars tests that rely on SCEV expansion to -loop-reduce tests.Andrew Trick2012-03-22
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153259 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR: teach isSimplifiedLoopNest to handle PHI IVUsers.Andrew Trick2012-03-20
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153132 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR: fix IVUsers isSimplifiedLoopNest to perform a full domtree walkAndrew Trick2012-03-20
| | | | | | | | | instead of skipping the current loop. My prior fix was incomplete because of an overzealous compile-time optimization: Better fix for: <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153131 91177308-0d34-0410-b5e6-96231b3b80d8
* LSR fix: Add isSimplifiedLoopNest to IVUsers analysis.Andrew Trick2012-03-16
| | | | | | | | | | | | | | Only record IVUsers that are dominated by simplified loop headers. Otherwise SCEVExpander will crash while looking for a preheader. I previously tried to work around this in LSR itself, but that was insufficient. This way, LSR can continue to run if some uses are not in simple loops, as long as we don't attempt to analyze those users. Fixes <rdar://problem/11049788> Segmentation fault: 11 in LoopStrengthReduce git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152892 91177308-0d34-0410-b5e6-96231b3b80d8
* Move llc + target triple tests into X86Andrew Trick2012-03-10
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@152502 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix this assert. IP can point to an instruction with strange dominanceRafael Espindola2012-02-27
| | | | | | | properties (invoke). Just assert that the instruction we return dominates the insertion point. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151511 91177308-0d34-0410-b5e6-96231b3b80d8
* Change the implementation of dominates(inst, inst) to one based on what theRafael Espindola2012-02-26
| | | | | | | | verifier does. This correctly handles invoke. Thanks to Duncan, Andrew and Chris for the comments. Thanks to Joerg for the early testing. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151469 91177308-0d34-0410-b5e6-96231b3b80d8
* Semantically revert 151015. Add a comment on why we should be able to assertRafael Espindola2012-02-22
| | | | | | | | the dominance once the dominates method is fixed and why we can use the builder's insertion point. Fixes pr12048. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@151125 91177308-0d34-0410-b5e6-96231b3b80d8
* Don't skip debug instructions when looking for the insertion point ofRafael Espindola2012-02-18
| | | | | | | | | | | | | | | | | | | | | | | | | | | | the cast. If we do, we can end up with inst1 --------------- < Insertion point dbg inst new inst instead of the desired inst1 new inst --------------- < Insertion point dbg inst Another option would be for InsertNoopCastOfTo (or its callers) to move the insertion point and we would end up with inst1 dbg inst new inst --------------- < Insertion point but that complicates the callers. This fixes PR12018 (and firefox's build). git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150884 91177308-0d34-0410-b5e6-96231b3b80d8
* Replace all instances of dg.exp file with lit.local.cfg, since all tests are ↵Eli Bendersky2012-02-16
| | | | | | | | | | | run with LIT now and now Dejagnu. dg.exp is no longer needed. Patch reviewed by Daniel Dunbar. It will be followed by additional cleanup patches. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150664 91177308-0d34-0410-b5e6-96231b3b80d8
* Handle a corner case with IV chain collection with bailout instead of assert.Andrew Trick2012-01-20
| | | | | | | Fixes PR11783: bad cast to AddRecExpr. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148572 91177308-0d34-0410-b5e6-96231b3b80d8
* Test case comments missing from my previous checkin.Andrew Trick2012-01-20
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148571 91177308-0d34-0410-b5e6-96231b3b80d8
* SCEVExpander fixes. Affects LSR and indvars.Andrew Trick2012-01-20
| | | | | | | | | | | | | | | | | LSR has gradually been improved to more aggressively reuse existing code, particularly existing phi cycles. This exposed problems with the SCEVExpander's sloppy treatment of its insertion point. I applied some rigor to the insertion point problem that will hopefully avoid an endless bug cycle in this area. Changes: - Always used properlyDominates to check safe code hoisting. - The insertion point provided to SCEV is now considered a lower bound. This is usually a block terminator or the use itself. Under no cirumstance may SCEVExpander insert below this point. - LSR is reponsible for finding a "canonical" insertion point across expansion of different expressions. - Robust logic to determine whether IV increments are in "expanded" form and/or can be safely hoisted above some insertion point. Fixes PR11783: SCEVExpander assert. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@148535 91177308-0d34-0410-b5e6-96231b3b80d8