implement some fixme's: when deleting an instruction with
an entry in the nonlocal deps map, don't reset entries
referencing that instruction to [dirty, null], instead, set
them to [dirty,next] where next is the instruction after the
deleted one.  Use this information in the non-local deps
code to avoid rescanning entire blocks.

This speeds up GVN slightly by avoiding pointless work.  On
403.gcc this makes GVN 1.5% faster.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60256 91177308-0d34-0410-b5e6-96231b3b80d8

Change MemDep::getNonLocalDependency to return its results as
a smallvector instead of a DenseMap.  This speeds up GVN by 5%
on 403.gcc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60255 91177308-0d34-0410-b5e6-96231b3b80d8

move MemoryDependenceAnalysis::verifyRemoved to the end of the file,
no functionality/code change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60254 91177308-0d34-0410-b5e6-96231b3b80d8

reimplement getNonLocalDependency with a simpler worklist
formulation that is faster and doesn't require nonLazyHelper.
Much less code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60253 91177308-0d34-0410-b5e6-96231b3b80d8

don't require GVN to work on dead values, just make the
test return the loaded value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60252 91177308-0d34-0410-b5e6-96231b3b80d8

Fix a thinko that manifested as a crash on clamav last night.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60251 91177308-0d34-0410-b5e6-96231b3b80d8

Fix spelling mistake.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60250 91177308-0d34-0410-b5e6-96231b3b80d8

tidy up some variable names.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60243 91177308-0d34-0410-b5e6-96231b3b80d8

rename some maps.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60242 91177308-0d34-0410-b5e6-96231b3b80d8

rename some variables.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60241 91177308-0d34-0410-b5e6-96231b3b80d8

eliminate a bunch of code in favor of using AliasAnalysis::getModRefInfo.
Put a some code back to handle buggy behavior that GVN expects: it wants
loads to depend on each other, and accesses to depend on their allocations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60240 91177308-0d34-0410-b5e6-96231b3b80d8

protect against negative values that would exceed allowed bit width

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60239 91177308-0d34-0410-b5e6-96231b3b80d8

simplify some code and rename some variables.  Reduce nesting.
Use getTypeStoreSize instead of ABITypeSize for in-memory size
in a couple places.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60238 91177308-0d34-0410-b5e6-96231b3b80d8

apparently GCC doesn't believe that I understand C
precedence rules.  Pacify it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60237 91177308-0d34-0410-b5e6-96231b3b80d8

Typo fix.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60236 91177308-0d34-0410-b5e6-96231b3b80d8

Split getDependency into getDependency and getDependencyFrom, the
former does caching, the later doesn't.  This dramatically simplifies
the logic in getDependency and getDependencyFrom.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60234 91177308-0d34-0410-b5e6-96231b3b80d8

Temporarily revert r60195. It's causing an optimized bootstrap of llvm-gcc to fail.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60233 91177308-0d34-0410-b5e6-96231b3b80d8

Now that DepType is private, we can start cleaning up some of its uses:
Document the Dirty value more precisely, use it for the uninitialized
DepResultTy value.  Change reverse mappings to be from an instruction*
instead of DepResultTy, and stop tracking other forms.  This makes it more
clear that we only care about the instruction cases.

Eliminate a DepResultTy,bool pair by using Dirty in the local case as well,
shrinking the map and simplifying the code.

This speeds up GVN by ~3% on 403.gcc.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60232 91177308-0d34-0410-b5e6-96231b3b80d8

Introduce and use a new MemDepResult class to hold the results of a memdep
query.  This makes it crystal clear what cases can escape from MemDep that
the clients have to handle.  This also gives the clients a nice simplified
interface to it that is easy to poke at.

This patch also makes DepResultTy and MemoryDependenceAnalysis::DepType
private, yay.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60231 91177308-0d34-0410-b5e6-96231b3b80d8

Reimplement the internal abstraction used by MemDep in terms
of a pointer/int pair instead of a manually bitmangled pointer.
This forces clients to think a little more about checking the
appropriate pieces and will be useful for internal
implementation improvements later.

I'm not particularly happy with this.  After going through this
I don't think that the clients of memdep should be exposed to
the internal type at all.  I'll fix this in a subsequent commit.

This has no functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60230 91177308-0d34-0410-b5e6-96231b3b80d8

Fix sentinels to use correctly 'aligned' pointers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60229 91177308-0d34-0410-b5e6-96231b3b80d8

Fix spello, add DenseMapInfo specialization for PointerIntPair.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60228 91177308-0d34-0410-b5e6-96231b3b80d8

fix comment typo

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60227 91177308-0d34-0410-b5e6-96231b3b80d8

fix a bug.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60225 91177308-0d34-0410-b5e6-96231b3b80d8

add a generic "bitmangled pointer" class, which allows a parameterized
pointer and integer type to be used.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60224 91177308-0d34-0410-b5e6-96231b3b80d8

Fix PR3141 by ensuring that MemoryDependenceAnalysis::removeInstruction
properly updates the reverse dependency map when it installs updated
dependencies for instructions that depend on the removed instruction.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60222 91177308-0d34-0410-b5e6-96231b3b80d8

don't revisit instructions off the beginning of the block.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60221 91177308-0d34-0410-b5e6-96231b3b80d8

comment cleanups.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60220 91177308-0d34-0410-b5e6-96231b3b80d8

more cleanups for MemoryDependenceAnalysis::removeInstruction,
no functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60219 91177308-0d34-0410-b5e6-96231b3b80d8

random cleanups, no functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60218 91177308-0d34-0410-b5e6-96231b3b80d8

forward declare CallSite instead of #includ'ing it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60217 91177308-0d34-0410-b5e6-96231b3b80d8

Run verifyRemoved from removeInstruction when -debug is specified.
This shows the root problem behind PR3141.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60216 91177308-0d34-0410-b5e6-96231b3b80d8

rename "ping" to "verifyRemoved".  I don't know why 'ping' what chosen,
but it doesn't make any sense at all.

Also make the method const, private, and fit in 80 cols while we're at it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60215 91177308-0d34-0410-b5e6-96231b3b80d8

comment and indentation improvements.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60214 91177308-0d34-0410-b5e6-96231b3b80d8

simplify some code, remove escaped newline.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60213 91177308-0d34-0410-b5e6-96231b3b80d8

remove mysterious escaped newlines.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60211 91177308-0d34-0410-b5e6-96231b3b80d8

don't call MergeBasicBlockIntoOnlyPred on a block whose only
predecessor is itself.  This doesn't make sense, and this is
a dead infinite loop anyway.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60210 91177308-0d34-0410-b5e6-96231b3b80d8

Add include files needed when building with
gcc 4.4 (due to use of sprintf).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60209 91177308-0d34-0410-b5e6-96231b3b80d8

Fix build with gcc-4.4: it doesn't like PICStyle
being both a namespace and a variable name.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60208 91177308-0d34-0410-b5e6-96231b3b80d8

rewrite RecursivelyDeleteTriviallyDeadInstructions to use a more efficient
formulation that doesn't require set lookups or scanning a set.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60203 91177308-0d34-0410-b5e6-96231b3b80d8

remove some weirdness that came from the LSR code that has
nothing to do with dead instruction elimination.  No tests in
dejagnu depend on this, so I don't know what it was needed for.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60202 91177308-0d34-0410-b5e6-96231b3b80d8

rewrite a big chunk of how DSE does recursive dead operand
elimination to use more modern infrastructure.  Also do a bunch
of small cleanups.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60201 91177308-0d34-0410-b5e6-96231b3b80d8

Scrap some boilerplate.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60200 91177308-0d34-0410-b5e6-96231b3b80d8

Support multiple compilation graph definitions. Not terribly useful, but makes the code more generic.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60199 91177308-0d34-0410-b5e6-96231b3b80d8

Add 'hidden' and 'really_hidden' option properties.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60198 91177308-0d34-0410-b5e6-96231b3b80d8

Documentation: clarify what is meant by 'multiple edges'.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60197 91177308-0d34-0410-b5e6-96231b3b80d8

delete ErasePossiblyDeadInstructionTree, replacing uses of it with
RecursivelyDeleteTriviallyDeadInstructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60196 91177308-0d34-0410-b5e6-96231b3b80d8

Simplify LoopStrengthReduce::DeleteTriviallyDeadInstructions by
making it use RecursivelyDeleteTriviallyDeadInstructions to do
the heavy lifting.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60195 91177308-0d34-0410-b5e6-96231b3b80d8

enhance RecursivelyDeleteTriviallyDeadInstructions to make
PHIs dead if they are single-value.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60194 91177308-0d34-0410-b5e6-96231b3b80d8

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

use continue to reduce indentation

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60192 91177308-0d34-0410-b5e6-96231b3b80d8

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

simplify code.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60190 91177308-0d34-0410-b5e6-96231b3b80d8

simplify this logic.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60189 91177308-0d34-0410-b5e6-96231b3b80d8

Also update the README.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60188 91177308-0d34-0410-b5e6-96231b3b80d8

Chris prefers icmp/select over udiv!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60187 91177308-0d34-0410-b5e6-96231b3b80d8

Add a synthetic missed optimization.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60186 91177308-0d34-0410-b5e6-96231b3b80d8

Add a couple of missed optimizations on integer vectors. Multiply and divide
by 1, as well as multiply by -1.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60182 91177308-0d34-0410-b5e6-96231b3b80d8

defensive patch: if CGP is merging a block with the entry block, make sure
it ends up being the entry block.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60180 91177308-0d34-0410-b5e6-96231b3b80d8

Fix PR3138: if we merge the entry block into another block, make sure to
move the other block back up into the entry position!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60179 91177308-0d34-0410-b5e6-96231b3b80d8

Silence a warning.

Despite changing the order of evaluation, this doesn't actually change the
meaning of the statement.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60177 91177308-0d34-0410-b5e6-96231b3b80d8

fix build on some machines. thanks buildbot

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60175 91177308-0d34-0410-b5e6-96231b3b80d8

fix my previous commit r60064: compare strings instead of pointers

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60174 91177308-0d34-0410-b5e6-96231b3b80d8

switch InstCombine::visitLoadInst to use
FindAvailableLoadedValue

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60169 91177308-0d34-0410-b5e6-96231b3b80d8

improve const correctness.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60168 91177308-0d34-0410-b5e6-96231b3b80d8

enhance FindAvailableLoadedValue to make use of AliasAnalysis
if it has it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60167 91177308-0d34-0410-b5e6-96231b3b80d8

move FindAvailableLoadedValue from JumpThreading to Transforms/Utils.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60166 91177308-0d34-0410-b5e6-96231b3b80d8

Get rid of bogus "control may reach end of non-void function ‘...’ being
inlined" message.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60165 91177308-0d34-0410-b5e6-96231b3b80d8

simplify this code a bit.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60164 91177308-0d34-0410-b5e6-96231b3b80d8

Use the new MergeBasicBlockIntoOnlyPred function.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60163 91177308-0d34-0410-b5e6-96231b3b80d8

move MergeBasicBlockIntoOnlyPred to Transforms/Utils.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60162 91177308-0d34-0410-b5e6-96231b3b80d8

XFAil test due to reverting of patch.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60161 91177308-0d34-0410-b5e6-96231b3b80d8

rename ThreadBlock to ProcessBlock, since it does other things than
just simple threading.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60157 91177308-0d34-0410-b5e6-96231b3b80d8

Comment out code that isn't entirely correct.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60156 91177308-0d34-0410-b5e6-96231b3b80d8

Fixed HTML closing tag, cleaned up some spacing.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60153 91177308-0d34-0410-b5e6-96231b3b80d8

Removing redundant semicolons. No functionality change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60149 91177308-0d34-0410-b5e6-96231b3b80d8

Make jump threading substantially more powerful, in the following ways:

1. Make it fold blocks separated by an unconditional branch.  This enables
   jump threading to see a broader scope.
2. Make jump threading able to eliminate locally redundant loads when they
   feed the branch condition of a block.  This frequently occurs due to
   reg2mem running.
3. Make jump threading able to eliminate *partially redundant* loads when
   they feed the branch condition of a block.  This is common in code with
   lots of loads and stores like C++ code and 255.vortex.

This implements thread-loads.ll and rdar://6402033.

Per the fixme's, several pieces of this should be moved into Transforms/Utils.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60148 91177308-0d34-0410-b5e6-96231b3b80d8

Eliminate a compile time warning.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60145 91177308-0d34-0410-b5e6-96231b3b80d8

Avoid inserting noop's in the middle of a loop.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60141 91177308-0d34-0410-b5e6-96231b3b80d8

On x86 favors folding short immediate into some arithmetic operations (e.g. add, and, xor, etc.) because materializing an immediate in a register is expensive in turns of code size.
e.g.
movl 4(%esp), %eax
addl $4, %eax

is 2 bytes shorter than

movl $4, %eax
addl 4(%esp), %eax

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60139 91177308-0d34-0410-b5e6-96231b3b80d8

Add a missing case in visitADD.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60137 91177308-0d34-0410-b5e6-96231b3b80d8

Add -march=x86.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60135 91177308-0d34-0410-b5e6-96231b3b80d8

Add typedef to StringMapEntry.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60134 91177308-0d34-0410-b5e6-96231b3b80d8

Disallow multiple edges.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60127 91177308-0d34-0410-b5e6-96231b3b80d8

Add x86-specific test for add-with-overflow intrinsics.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60125 91177308-0d34-0410-b5e6-96231b3b80d8

Generate something sensible for an [SU]ADDO op when the overflow/carry flag is
the conditional for the BRCOND statement. For instance, it will generate:

    addl %eax, %ecx
    jo LOF

instead of

    addl %eax, %ecx
    ; About 10 instructions to compare the signs of LHS, RHS, and sum.
    jl LOF

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60123 91177308-0d34-0410-b5e6-96231b3b80d8

Turn on my codegen prepare heuristic by default.  It doesn't affect
performance in most cases on the Grawp tester, but does speed some
things up (like shootout/hash by 15%).  This also doesn't impact
compile time in a noticable way on the Grawp tester.

It also, of course, gets the testcase it was designed for right :)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60120 91177308-0d34-0410-b5e6-96231b3b80d8

Small formatting change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60113 91177308-0d34-0410-b5e6-96231b3b80d8

Update to explain how ssp and sspreq attributes override each other.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60112 91177308-0d34-0410-b5e6-96231b3b80d8

Fix typo.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60111 91177308-0d34-0410-b5e6-96231b3b80d8

Cosmetic.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60110 91177308-0d34-0410-b5e6-96231b3b80d8

Check that running the DAG combiner between type
and operation legalization does something useful.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60108 91177308-0d34-0410-b5e6-96231b3b80d8

Describe some more options in the man page.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60105 91177308-0d34-0410-b5e6-96231b3b80d8

ignore build dirs and generated files

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60104 91177308-0d34-0410-b5e6-96231b3b80d8

Allow custom lowering of ADDE/ADDC/SUBE/SUBC operations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60102 91177308-0d34-0410-b5e6-96231b3b80d8

Fix the -I option (llvmc -I dir1 -I dir2 didn't work).

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60101 91177308-0d34-0410-b5e6-96231b3b80d8

Refactor Tools.td to remove repetition.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60100 91177308-0d34-0410-b5e6-96231b3b80d8

Small fix: the error message was incorrect in some cases.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60099 91177308-0d34-0410-b5e6-96231b3b80d8

Emit declaration for globals and externs.
Custom lower AND, OR, XOR bitwise operations.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60098 91177308-0d34-0410-b5e6-96231b3b80d8

Fish kill flag annotations in PUSH instructions.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60095 91177308-0d34-0410-b5e6-96231b3b80d8