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2009-01-20another fix for PR3354Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62561 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-19Doxygen-ify comments.Bill Wendling
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62546 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-19Fix a problem exposed by PR3354: simplifycfg was making a potentiallyChris Lattner
trapping instruction be executed unconditionally. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62541 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-19Temporarily revert r62487. It's causing this error during a release bootstrap ofBill Wendling
llvm-gcc. Most likely, it's miscompiling one of the "gen*" programs: /Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm-gcc.obj/./prev-gcc/xgcc -B/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm-gcc.obj/./prev-gcc/ -B/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm-gcc.install/i386-apple-darwin9.6.0/bin/ -c -g -O2 -mdynamic-no-pic -DIN_GCC -W -Wall -Wwrite-strings -Wstrict-prototypes -Wmissing-prototypes -mdynamic-no-pic -DHAVE_CONFIG_H -DGENERATOR_FILE -I. -Ibuild -I../../llvm-gcc.src/gcc -I../../llvm-gcc.src/gcc/build -I../../llvm-gcc.src/gcc/../include -I./../intl -I../../llvm-gcc.src/gcc/../libcpp/include -I../../llvm-gcc.src/gcc/../libdecnumber -I../libdecnumber -I/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.obj/include -I/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.src/include -DENABLE_LLVM -I/Volumes/Sandbox/Buildbot/llvm/full-llvm/build/llvm.obj/../llvm.src/include -D_DEBUG -D_GNU_SOURCE -D__STDC_LIMIT_MACROS -D__STDC_CONSTANT_MACROS -o build/gencondmd.o build/gencondmd.c ../../llvm-gcc.src/gcc/config/i386/mmx.md:926: error: expected '}' before ')' token ../../llvm-gcc.src/gcc/config/i386/mmx.md:926: warning: excess elements in struct initializer ../../llvm-gcc.src/gcc/config/i386/mmx.md:926: warning: (near initialization for 'insn_conditions[4]') ../../llvm-gcc.src/gcc/config/i386/mmx.md:926: error: expected '}' before ')' token ../../llvm-gcc.src/gcc/config/i386/mmx.md:926: error: expected ',' or ';' before ')' token ../../llvm-gcc.src/gcc/config/i386/mmx.md:927: error: expected identifier or '(' before ',' token ../../llvm-gcc.src/gcc/config/i386/sse.md:3458: error: expected identifier or '(' before ',' token ... git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62506 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-19Fix PR3016, a bug which can occur do to an invalid assumption:Chris Lattner
we assumed a CFG structure that would be valid when all code in the function is reachable, but not all code is necessarily reachable. Do a simple, but horrible, CFG walk to check for this case. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62487 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-19reduce indentation by using 'continue', no functionality change.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62477 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-19Fix some problems in SpeculativelyExecuteBB. Basically,Chris Lattner
because of dead code, a phi could use the speculated instruction that was not in "BB2". Make this check explicit and tighten up some other corners. This fixes PR3292. No testcase becauase this depends entirely on visitation order of blocks and requires a sequence of 8 passes to repro. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62476 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-18Make this a bit more explicit about which cases need the Chris Lattner
check. No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62474 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16Add a helper to remove a branch and DCE the condition, and use it Eli Friedman
consistently for deleting branches. In addition to being slightly more readable, this makes SimplifyCFG a bit better about cleaning up after itself when it makes conditions unused. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61100 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-07fix a bug I introduced in simplifycfg handling single entry phi Chris Lattner
nodes. FoldSingleEntryPHINodes deletes the PHI, so there is no need to delete it afterward. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60653 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03Factor some code into a new FoldSingleEntryPHINodes method.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60501 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03Rename DeleteBlockIfDead to DeleteDeadBlock and make it Chris Lattner
unconditionally delete the block. All likely clients will do the checking anyway. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60464 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03Factor some code out of SimplifyCFG, forming a new Chris Lattner
DeleteBlockIfDead method. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60463 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27delete ErasePossiblyDeadInstructionTree, replacing uses of it withChris Lattner
RecursivelyDeleteTriviallyDeadInstructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60196 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27simplify this code a bit.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60164 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-29Fix PR2967 by not deleting volatile load/stores that occur before unreachable.Chris Lattner
I don't really see this as being needed, but there is little harm from doing it. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@58385 91177308-0d34-0410-b5e6-96231b3b80d8
2008-10-03Nick Lewycky's patch.Devang Patel
While hosting instruction check PHI node. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57025 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-25 Large mechanical patch.Devang Patel
s/ParamAttr/Attribute/g s/PAList/AttrList/g s/FnAttributeWithIndex/AttributeWithIndex/g s/FnAttr/Attribute/g This sets the stage - to implement function notes as function attributes and - to distinguish between function attributes and return value attributes. This requires corresponding changes in llvm-gcc and clang. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56622 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-18Try to place hoisted instructions befoe icmp instruction.Devang Patel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56315 91177308-0d34-0410-b5e6-96231b3b80d8
2008-09-17Do not hoist instruction above branch condition. The instruction may use ↵Devang Patel
branch condition. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56286 91177308-0d34-0410-b5e6-96231b3b80d8
2008-08-14Use empty() instead of begin() == end().Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54780 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-23Enable first-class aggregates support.Dan Gohman
Remove the GetResultInst instruction. It is still accepted in LLVM assembly and bitcode, where it is now auto-upgraded to ExtractValueInst. Also, remove support for return instructions with multiple values. These are auto-upgraded to use InsertValueInst instructions. The IRBuilder still accepts multiple-value returns, and auto-upgrades them to InsertValueInst instructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53941 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-18Reapply r53735. My last patch fixed the failures Dan observed.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53761 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-18Revert r53735. It broke SPEC 464.h264ref.Dan Gohman
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53757 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-17Use MergeBlockIntoPredecessor to simplify some code.Owen Anderson
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53735 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-13Fix mishandling of the infinite loop case when merging two blocks. ThisChris Lattner
fixes PR2540. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53533 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-13more refactoring. Use early exits instead of really complex logic.Chris Lattner
No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53532 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-13improve comments.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53531 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-13factor another large hunk of code out into its own function. Chris Lattner
No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53530 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-13Final bit of simplification for FoldBranchToCommonDest.Chris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53528 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-13simplify logic a bitChris Lattner
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53527 91177308-0d34-0410-b5e6-96231b3b80d8
2008-07-13Refactor some code out into its own helper function, getting rid of crazy ↵Chris Lattner
multiline conditionals and commenting the code better. No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53526 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-25- Use O(1) check of basic block size limit.Evan Cheng
- Avoid speculatively execute vector ops. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52703 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-12Do not speculatively execute an instruction by hoisting it to its ↵Evan Cheng
predecessor BB if any of its operands are defined but not used in BB. The transformation will prevent the operand from being sunk into the use block. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52244 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-11For now, avoid generating FP select instructions in order to speculatively ↵Evan Cheng
execute integer arithmetic instructions. FP selects are more likely to be expensive (even compared to branch on fcmp). This is not a wonderful solution but I rather err on the side of conservative. This fixes the heapsort performance regressions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52224 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-10op_iterator-ify loopsGabor Greif
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52191 91177308-0d34-0410-b5e6-96231b3b80d8
2008-06-07Speculatively execute a block when the the block is the then part of a ↵Evan Cheng
triangle shape and it contains a single, side effect free, cheap instruction. The branch is eliminated by adding a select instruction. i.e. Turn BB: %t1 = icmp br i1 %t1, label %BB1, label %BB2 BB1: %t3 = add %t2, c br label BB2 BB2: => BB: %t1 = icmp %t4 = add %t2, c %t3 = select i1 %t1, %t2, %t3 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52073 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-23Tidy up BasicBlock::getFirstNonPHI, and change a bunch of places toDan Gohman
use it instead of duplicating its functionality. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51499 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-23Restucture a part of the SimplifyCFG pass and include a testcase.Matthijs Kooijman
The SimplifyCFG pass looks at basic blocks that contain only phi nodes, followed by an unconditional branch. In a lot of cases, such a block (BB) can be merged into their successor (Succ). This merging is performed by TryToSimplifyUncondBranchFromEmptyBlock. It does this by taking all phi nodes in the succesor block Succ and expanding them to include the predecessors of BB. Furthermore, any phi nodes in BB are moved to Succ and expanded to include the predecessors of Succ as well. Before attempting this merge, CanPropagatePredecessorsForPHIs checks to see if all phi nodes can be properly merged. All functional changes are made to this function, only comments were updated in TryToSimplifyUncondBranchFromEmptyBlock. In the original code, CanPropagatePredecessorsForPHIs looks quite convoluted and more like stack of checks added to handle different kinds of situations than a comprehensive check. In particular the first check in the function did some value checking for the case that BB and Succ have a common predecessor, while the last check in the function simply rejected all cases where BB and Succ have a common predecessor. The first check was still useful in the case that BB did not contain any phi nodes at all, though, so it was not completely useless. Now, CanPropagatePredecessorsForPHIs is restructured to to look a lot more similar to the code that actually performs the merge. Both functions now look at the same phi nodes in about the same order. Any conflicts (phi nodes with different values for the same source) that could arise from merging or moving phi nodes are detected. If no conflicts are found, the merge can happen. Apart from only restructuring the checks, two main changes in functionality happened. Firstly, the old code rejected blocks with common predecessors in most cases. The new code performs some extra checks so common predecessors can be handled in a lot of cases. Wherever common predecessors still pose problems, the blocks are left untouched. Secondly, the old code rejected the merge when values (phi nodes) from BB were used in any other place than Succ. However, it does not seem that there is any situation that would require this check. Even more, this can be proven. Consider that BB is a block containing of a single phi node "%a" and a branch to Succ. Now, since the definition of %a will dominate all of its uses, BB will dominate all blocks that use %a. Furthermore, since the branch from BB to Succ is unconditional, Succ will also dominate all uses of %a. Now, assume that one predecessor of Succ is not dominated by BB (and thus not dominated by Succ). Since at least one use of %a (but in reality all of them) is reachable from Succ, you could end up at a use of %a without passing through it's definition in BB (by coming from X through Succ). This is a contradiction, meaning that our original assumption is wrong. Thus, all predecessors of Succ must also be dominated by BB (and thus also by Succ). This means that moving the phi node %a from BB to Succ does not pose any problems when the two blocks are merged, and any use checks are not needed. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51478 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-16API change for {BinaryOperator|CmpInst|CastInst}::create*() --> Create. ↵Gabor Greif
Legacy interfaces will be in place for some time. (Merge from use-diet branch.) git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51200 91177308-0d34-0410-b5e6-96231b3b80d8
2008-05-15Fix a bunch of 80col violations that arose from the Create API change. Tweak ↵Gabor Greif
makefile targets to find these better. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51143 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-28Fix PR2256, yet another miscompilation in simplifycfg of iChris Lattner
multiple return values. Bill, please pull this into Tak. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50332 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-25Remove 'unwinds to' support from mainline. This patch undoes r47802 r47989Nick Lewycky
r48047 r48084 r48085 r48086 r48088 r48096 r48099 r48109 and r48123. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50265 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-24Split some code out of the main SimplifyCFG loop into its own function.Chris Lattner
Fix said code to handle merging return instructions together correctly when handling multiple return values. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50199 91177308-0d34-0410-b5e6-96231b3b80d8
2008-04-06API changes for class Use size reduction, wave 1.Gabor Greif
Specifically, introduction of XXX::Create methods for Users that have a potentially variable number of Uses. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@49277 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-11Check to see if a two-entry PHI block can be simplifiedDan Gohman
before trying to merge the block into its predecessors. This allows two-entry-phi-return.ll to be simplified into a single basic block. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48252 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-10Turn unwind_to into "unwinds to".Nick Lewycky
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48123 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-09Firstly, having a BranchInst isn't exclusive with having an unwind_to.Nick Lewycky
Secondly, we have to check whether the branch is actually pointing to the block with the unwind in it. We could have gotten here because of the unwind_to alone. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48099 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-09A BB that unwind_to an "unwind" inst is that same as one that doesn't unwind_toNick Lewycky
at all. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48096 91177308-0d34-0410-b5e6-96231b3b80d8
2008-03-09Update the inliner and simplifycfg to handle unwind_to.Nick Lewycky
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@48086 91177308-0d34-0410-b5e6-96231b3b80d8
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