Commit Graph

62 Commits

Author SHA1 Message Date
Jakob Stoklund Olesen
58e9ee85fd Teach SimplifyCFG about magic pointer constants.
Weird code sometimes uses pointer constants other than null. This patch
teaches SimplifyCFG to build switch instructions in those cases.

Code like this:

void f(const char *x) {
  if (!x)
    puts("null");
  else if ((uintptr_t)x == 1)
    puts("one");
  else if (x == (char*)2 || x == (char*)3)
    puts("two");
  else if ((intptr_t)x == 4)
    puts("four");
  else
    puts(x);
}

Now becomes a switch:

define void @f(i8* %x) nounwind ssp {
entry:
  %magicptr23 = ptrtoint i8* %x to i64            ; <i64> [#uses=1]
  switch i64 %magicptr23, label %if.else16 [
    i64 0, label %if.then
    i64 1, label %if.then2
    i64 2, label %if.then9
    i64 3, label %if.then9
    i64 4, label %if.then14
  ]

Note that LLVM's own DenseMap uses magic pointers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@95439 91177308-0d34-0410-b5e6-96231b3b80d8
2010-02-05 22:03:18 +00:00
Bob Wilson
49db68fba0 Check alignment of loads when deciding whether it is safe to execute them
unconditionally.  Besides checking the offset, also check that the underlying
object is aligned as much as the load itself.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94875 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-30 04:42:39 +00:00
Bob Wilson
3eb4f7e2dd Improve isSafeToLoadUnconditionally to recognize that GEPs with constant
indices are safe if the result is known to be within the bounds of the
underlying object.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94829 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-29 19:19:08 +00:00
Victor Hernandez
6c146eefbf DbgInfoIntrinsics no longer appear in an instruction's use list; so clean up looking for them in use iterations and remove OnlyUsedByDbgInfoIntrinsics()
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@94111 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-21 23:05:53 +00:00
Chris Lattner
e234a30a28 add a helper function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@93251 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-12 19:40:54 +00:00
Dan Gohman
90fe0bd68c Make RecursivelyDeleteTriviallyDeadInstructions,
RecursivelyDeleteDeadPHINode, and DeleteDeadPHIs return a flag
indicating whether they made any changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92732 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 15:45:31 +00:00
Chris Lattner
43fd9017a6 convert various IntrinsicInst's to use class instead of struct.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@92681 91177308-0d34-0410-b5e6-96231b3b80d8
2010-01-05 05:21:26 +00:00
Dan Gohman
43ea505fb0 Eliminate unnecessary LLVMContexts.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@91729 91177308-0d34-0410-b5e6-96231b3b80d8
2009-12-18 23:42:08 +00:00
Jim Grosbach
20f4d34fe3 Make EliminateDuplicatePHINodes() available as a utility function
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@89297 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-19 02:02:10 +00:00
Chris Lattner
40d8c28b27 move some generally useful functions out of jump threading
into libanalysis and transformutils.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86735 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 22:26:15 +00:00
Chris Lattner
dce94d92df refactor TryToSimplifyUncondBranchFromEmptyBlock out of SimplifyCFG.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@86666 91177308-0d34-0410-b5e6-96231b3b80d8
2009-11-10 05:59:26 +00:00
Andreas Neustifter
ad80981a10 Preserve ProfileInfo during CodeGenPrepare.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@82034 91177308-0d34-0410-b5e6-96231b3b80d8
2009-09-16 09:26:52 +00:00
Benjamin Kramer
12ddd40953 Make LLVMContext and LLVMContextImpl classes instead of structs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78690 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-11 17:45:13 +00:00
Owen Anderson
48b2f3e485 Factor some of the constants+context related code out into a separate header, to make LLVMContextImpl.h
not hideous.  Also, fix some MSVC compile errors.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@78115 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-04 22:41:48 +00:00
Owen Anderson
50dead06ff Revert yesterday's change by removing the LLVMContext parameter to AllocaInst and MallocInst.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75863 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-15 23:53:25 +00:00
Owen Anderson
9adc0abad3 Move EVER MORE stuff over to LLVMContext.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75703 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-14 23:09:55 +00:00
Dan Gohman
4b35f83b91 Teach LoopSimplify how to merge multiple loop exits into a single exit,
when one of them can be converted to a trivial icmp and conditional
branch.

This addresses what is essentially a phase ordering problem.
SimplifyCFG knows how to do this transformation, but it doesn't do so
if the primary block has any instructions in it other than an icmp and
a branch. In the given testcase, the block contains other instructions,
however they are loop-invariant and can be hoisted. SimplifyCFG doesn't
have LoopInfo though, so it can't hoist them. And, it's important that
the blocks be merged before LoopRotation, as it doesn't support
multiple-exit loops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74396 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-27 21:30:38 +00:00
Devang Patel
acec7b35aa Remove unused routines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@74351 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-26 22:53:22 +00:00
Chris Lattner
6cc8a93c48 Generalize instcombine's isSafeToLoadUnconditionally() function
to ignore readonly calls, and factor it out of instcombine so
that it can be used by other passes.  Patch by Frits van Bommel!



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@73506 91177308-0d34-0410-b5e6-96231b3b80d8
2009-06-16 17:23:12 +00:00
Dan Gohman
35738ac150 Re-apply 70645, converting ScalarEvolution to use
CallbackVH, with fixes. allUsesReplacedWith need to
walk the def-use chains and invalidate all users of a
value that is replaced. SCEVs of users need to be
recalcualted even if the new value is equivalent. Also,
make forgetLoopPHIs walk def-use chains, since any
SCEV that depends on a PHI should be recalculated when
more information about that PHI becomes available.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70927 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-04 22:30:44 +00:00
Dan Gohman
f9a77b77c2 Revert r70645 for now; it's causing a variety of regressions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70661 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-03 05:46:20 +00:00
Dan Gohman
db6fa29641 Convert ScalarEvolution to use CallbackVH for its internal map. This
makes ScalarEvolution::deleteValueFromRecords, and it's code that
subtly needed to be called before ReplaceAllUsesWith, unnecessary.

It also makes ValueDeletionListener unnecessary.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70645 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-02 21:19:20 +00:00
Dan Gohman
afc36a9520 Previously, RecursivelyDeleteDeadInstructions provided an option
of returning a list of pointers to Values that are deleted. This was
unsafe, because the pointers in the list are, by nature of what
RecursivelyDeleteDeadInstructions does, always dangling. Replace this
with a simple callback mechanism. This may eventually be removed if
all clients can reasonably be expected to use CallbackVH.

Use this to factor out the dead-phi-cycle-elimination code from LSR
utility function, and generalize it to use the
RecursivelyDeleteTriviallyDeadInstructions utility function.

This makes LSR more aggressive about eliminating dead PHI cycles;
adjust tests to either be less trivial or to simply expect fewer
instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@70636 91177308-0d34-0410-b5e6-96231b3b80d8
2009-05-02 18:29:22 +00:00
Devang Patel
c79e118247 Add "check/remove dbg var" helper routines.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@66223 91177308-0d34-0410-b5e6-96231b3b80d8
2009-03-06 00:19:37 +00:00
Cedric Venet
aff9c270de Unbreak the build on win32.
Cleanup some warning.

Remark: when struct/class are declared differently than they are defined, this make problem for VC++ since it seems to mangle class differently that struct. These error are very hard to understand and find. So please, try to keep your definition/declaration in sync.

Only tested with VS2008. hope it does not break anything. feel free to revert.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64554 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-14 16:06:42 +00:00
Devang Patel
4afc90dacf Enable scalar replacement of AllocaInst whose one of the user is dbg info.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@64207 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-10 07:00:59 +00:00
Devang Patel
998cbb0444 Revert rev. 63876. It is causing llvm-gcc bootstrap failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63888 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-05 21:46:41 +00:00
Devang Patel
1851db6b0f Ignore dbg intrinsics while propagating conditional expression info.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@63876 91177308-0d34-0410-b5e6-96231b3b80d8
2009-02-05 19:15:39 +00:00
Dan Gohman
d68a07650c Tidy up #includes, deleting a bunch of unnecessary #includes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61715 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-05 17:59:02 +00:00
Chris Lattner
29874e0dc6 Factor some code into a new FoldSingleEntryPHINodes method.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60501 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03 19:44:02 +00:00
Chris Lattner
4f02c74a8e Enhance RecursivelyDeleteTriviallyDeadInstructions to optionally
return a list of deleted instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60193 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 23:14:34 +00:00
Chris Lattner
3481f24c06 remove doConstantPropagation and dceInstruction, they are just
wrappers around the interesting code and use an obscure iterator
abstraction that dates back many many years.

Move EraseDeadInstructions to Transforms/Utils and name it
RecursivelyDeleteTriviallyDeadInstructions.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60191 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 22:57:53 +00:00
Chris Lattner
b29714a10a move MergeBasicBlockIntoOnlyPred to Transforms/Utils.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60162 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-27 07:43:12 +00:00
Chris Lattner
7ed47a1335 Don't attribute in file headers anymore. See llvmdev for the
discussion of this change.  Boy are my fingers tired. ;-)



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@45411 91177308-0d34-0410-b5e6-96231b3b80d8
2007-12-29 19:59:42 +00:00
Anton Korobeynikov
a024e8ceda Reg2Mem cleanup and optimizations:
- enable phi instructions demotion to stack
 - create alloca instructions in the entry block


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@43208 91177308-0d34-0410-b5e6-96231b3b80d8
2007-10-21 23:05:16 +00:00
Tanya Lattner
08d14d2469 Adding ability to demote phi to stack.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@39744 91177308-0d34-0410-b5e6-96231b3b80d8
2007-07-11 18:41:34 +00:00
Chris Lattner
997c74ce35 move constant folding code out of Utils/Local into libanalysis
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33681 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-30 23:46:43 +00:00
Chris Lattner
73259caa44 Change constant folding APIs to take an optional TargetData, and change
ConstantFoldInstOperands/ConstantFoldCall to take a pointer to an array
of operands + size, instead of an std::vector.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33669 91177308-0d34-0410-b5e6-96231b3b80d8
2007-01-30 23:12:47 +00:00
Reid Spencer
e4d87aa2de For PR950:
This patch removes the SetCC instructions and replaces them with the ICmp
and FCmp instructions. The SetCondInst instruction has been removed and
been replaced with ICmpInst and FCmpInst.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@32751 91177308-0d34-0410-b5e6-96231b3b80d8
2006-12-23 06:05:41 +00:00
Chris Lattner
b5a554ec80 Add an interface to constant fold and instruction given it's opcode, type
and operands.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@28516 91177308-0d34-0410-b5e6-96231b3b80d8
2006-05-27 01:17:40 +00:00
John Criswell
bd9d37026a Move some constant folding functions into LLVMAnalysis since they are used
by Analysis and Transformation passes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24038 91177308-0d34-0410-b5e6-96231b3b80d8
2005-10-27 16:00:10 +00:00
Chris Lattner
cc0f703f42 allow demotion to volatile values
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23472 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-27 19:38:43 +00:00
Chris Lattner
c5406b55d5 add a new function
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23443 91177308-0d34-0410-b5e6-96231b3b80d8
2005-09-26 05:26:32 +00:00
Nate Begeman
a83ba0f5c9 Fix a fixme in CondPropagate.cpp by moving a PhiNode optimization into
BasicBlock's removePredecessor routine.  This requires shuffling around
the definition and implementation of hasContantValue from Utils.h,cpp into
Instructions.h,cpp


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22664 91177308-0d34-0410-b5e6-96231b3b80d8
2005-08-04 23:24:19 +00:00
Misha Brukman
34695381d6 Remove trailing whitespace
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21412 91177308-0d34-0410-b5e6-96231b3b80d8
2005-04-21 20:59:05 +00:00
Chris Lattner
a2631b0225 Add new interfaces
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12918 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 19:28:32 +00:00
Chris Lattner
8f71b63bea cleanup comment
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12463 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-17 01:29:36 +00:00
Chris Lattner
cbf99ee973 Move DemoteRegToStack prototype out of DemoteRegToStack.h to this file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12367 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-14 02:13:07 +00:00
Chris Lattner
77ab3f1c89 llvm::ConstantFoldInstruction
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10787 91177308-0d34-0410-b5e6-96231b3b80d8
2004-01-12 18:25:56 +00:00
Chris Lattner
abbc2dd779 Add new function
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@10529 91177308-0d34-0410-b5e6-96231b3b80d8
2003-12-19 05:56:28 +00:00