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* While folding unconditional return move DbgRegionEndInst into the ↵Devang Patel2009-02-241-1/+8
| | | | | | | | | | | | | predecessor, instead of removing it. This fixes following tests from llvmgcc42 testsuite. gcc.c-torture/execute/20000605-3.c gcc.c-torture/execute/20020619-1.c gcc.c-torture/execute/20030920-1.c gcc.c-torture/execute/loop-ivopts-1.c git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@65353 91177308-0d34-0410-b5e6-96231b3b80d8
* If llvm.dbg.region.end is disappearing then remove corresponding ↵Devang Patel2009-02-111-1/+1
| | | | | | llvm.dbg.func.start also. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64278 91177308-0d34-0410-b5e6-96231b3b80d8
* Ignore dbg intrinsic while folding unconditional branch.Devang Patel2009-02-101-1/+2
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64242 91177308-0d34-0410-b5e6-96231b3b80d8
* Revert rev. 63876. It is causing llvm-gcc bootstrap failure.Devang Patel2009-02-051-0/+14
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63888 91177308-0d34-0410-b5e6-96231b3b80d8
* Ignore dbg intrinsics while propagating conditional expression info.Devang Patel2009-02-051-14/+0
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63876 91177308-0d34-0410-b5e6-96231b3b80d8
* Ignore dbg intrinsics while folding switch instruction.Devang Patel2009-02-051-8/+19
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63802 91177308-0d34-0410-b5e6-96231b3b80d8
* Ignore dbg intrinsics.Devang Patel2009-02-041-7/+29
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63781 91177308-0d34-0410-b5e6-96231b3b80d8
* While folding vallue comparison terminators ignore dbg intrinsics.Devang Patel2009-02-041-0/+3
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63700 91177308-0d34-0410-b5e6-96231b3b80d8
* Ignore dbg intrinsics while hoisting common code in the two blocks up into ↵Devang Patel2009-02-041-3/+14
| | | | | | the branch block. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63687 91177308-0d34-0410-b5e6-96231b3b80d8
* Do not let dbg intrinsic block folding of two entry phi node.Devang Patel2009-02-031-2/+3
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63671 91177308-0d34-0410-b5e6-96231b3b80d8
* another fix for PR3354Chris Lattner2009-01-201-0/+5
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62561 91177308-0d34-0410-b5e6-96231b3b80d8
* Doxygen-ify comments.Bill Wendling2009-01-191-45/+43
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62546 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix a problem exposed by PR3354: simplifycfg was making a potentiallyChris Lattner2009-01-191-1/+14
| | | | | | | trapping instruction be executed unconditionally. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62541 91177308-0d34-0410-b5e6-96231b3b80d8
* Temporarily revert r62487. It's causing this error during a release bootstrap ofBill Wendling2009-01-191-77/+2
| | | | | | | | | | | | | | | | | | 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
* Fix PR3016, a bug which can occur do to an invalid assumption:Chris Lattner2009-01-191-2/+77
| | | | | | | | | | 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
* reduce indentation by using 'continue', no functionality change.Chris Lattner2009-01-191-20/+22
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62477 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix some problems in SpeculativelyExecuteBB. Basically,Chris Lattner2009-01-191-5/+16
| | | | | | | | | | | | 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
* Make this a bit more explicit about which cases need the Chris Lattner2009-01-181-2/+6
| | | | | | | check. No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62474 91177308-0d34-0410-b5e6-96231b3b80d8
* Add a helper to remove a branch and DCE the condition, and use it Eli Friedman2008-12-161-32/+25
| | | | | | | | | | 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
* fix a bug I introduced in simplifycfg handling single entry phi Chris Lattner2008-12-071-1/+0
| | | | | | | | 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
* Factor some code into a new FoldSingleEntryPHINodes method.Chris Lattner2008-12-031-4/+1
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60501 91177308-0d34-0410-b5e6-96231b3b80d8
* Rename DeleteBlockIfDead to DeleteDeadBlock and make it Chris Lattner2008-12-031-1/+1
| | | | | | | | 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
* Factor some code out of SimplifyCFG, forming a new Chris Lattner2008-12-031-21/+1
| | | | | | | DeleteBlockIfDead method. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60463 91177308-0d34-0410-b5e6-96231b3b80d8
* delete ErasePossiblyDeadInstructionTree, replacing uses of it withChris Lattner2008-11-271-41/+9
| | | | | | | RecursivelyDeleteTriviallyDeadInstructions. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60196 91177308-0d34-0410-b5e6-96231b3b80d8
* simplify this code a bit.Chris Lattner2008-11-271-4/+4
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60164 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix PR2967 by not deleting volatile load/stores that occur before unreachable.Chris Lattner2008-10-291-0/+11
| | | | | | | | 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
* Nick Lewycky's patch.Devang Patel2008-10-031-1/+1
| | | | | | | | While hosting instruction check PHI node. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@57025 91177308-0d34-0410-b5e6-96231b3b80d8
* Large mechanical patch.Devang Patel2008-09-251-2/+2
| | | | | | | | | | | | | | | | | 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
* Try to place hoisted instructions befoe icmp instruction.Devang Patel2008-09-181-2/+23
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56315 91177308-0d34-0410-b5e6-96231b3b80d8
* Do not hoist instruction above branch condition. The instruction may use ↵Devang Patel2008-09-171-9/+2
| | | | | | branch condition. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56286 91177308-0d34-0410-b5e6-96231b3b80d8
* Use empty() instead of begin() == end().Dan Gohman2008-08-141-1/+1
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54780 91177308-0d34-0410-b5e6-96231b3b80d8
* Enable first-class aggregates support.Dan Gohman2008-07-231-43/+34
| | | | | | | | | | | | | 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
* Reapply r53735. My last patch fixed the failures Dan observed.Owen Anderson2008-07-181-52/+9
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53761 91177308-0d34-0410-b5e6-96231b3b80d8
* Revert r53735. It broke SPEC 464.h264ref.Dan Gohman2008-07-181-9/+52
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53757 91177308-0d34-0410-b5e6-96231b3b80d8
* Use MergeBlockIntoPredecessor to simplify some code.Owen Anderson2008-07-171-52/+9
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53735 91177308-0d34-0410-b5e6-96231b3b80d8
* Fix mishandling of the infinite loop case when merging two blocks. ThisChris Lattner2008-07-131-17/+26
| | | | | | | fixes PR2540. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53533 91177308-0d34-0410-b5e6-96231b3b80d8
* more refactoring. Use early exits instead of really complex logic.Chris Lattner2008-07-131-109/+98
| | | | | | | No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53532 91177308-0d34-0410-b5e6-96231b3b80d8
* improve comments.Chris Lattner2008-07-131-2/+4
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53531 91177308-0d34-0410-b5e6-96231b3b80d8
* factor another large hunk of code out into its own function. Chris Lattner2008-07-131-155/+172
| | | | | | | No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53530 91177308-0d34-0410-b5e6-96231b3b80d8
* Final bit of simplification for FoldBranchToCommonDest.Chris Lattner2008-07-131-32/+34
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53528 91177308-0d34-0410-b5e6-96231b3b80d8
* simplify logic a bitChris Lattner2008-07-131-9/+10
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@53527 91177308-0d34-0410-b5e6-96231b3b80d8
* Refactor some code out into its own helper function, getting rid of crazy ↵Chris Lattner2008-07-131-54/+84
| | | | | | | | | | | 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
* - Use O(1) check of basic block size limit.Evan Cheng2008-06-251-4/+8
| | | | | | | - Avoid speculatively execute vector ops. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52703 91177308-0d34-0410-b5e6-96231b3b80d8
* Do not speculatively execute an instruction by hoisting it to its ↵Evan Cheng2008-06-121-2/+16
| | | | | | 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
* For now, avoid generating FP select instructions in order to speculatively ↵Evan Cheng2008-06-111-4/+9
| | | | | | | | | 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
* op_iterator-ify loopsGabor Greif2008-06-101-13/+16
| | | | git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52191 91177308-0d34-0410-b5e6-96231b3b80d8
* Speculatively execute a block when the the block is the then part of a ↵Evan Cheng2008-06-071-0/+121
| | | | | | | | | | | | | | | | | | | | | 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
* Tidy up BasicBlock::getFirstNonPHI, and change a bunch of places toDan Gohman2008-05-231-2/+1
| | | | | | | use it instead of duplicating its functionality. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@51499 91177308-0d34-0410-b5e6-96231b3b80d8
* Restucture a part of the SimplifyCFG pass and include a testcase.Matthijs Kooijman2008-05-231-65/+99
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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
* API change for {BinaryOperator|CmpInst|CastInst}::create*() --> Create. ↵Gabor Greif2008-05-161-5/+5
| | | | | | 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