Tobias Grosser
cc21c4aa98
Instcombine: Fix pattern where the sext did not dominate the icmp using it
...
llvm-svn: 123121
2011-01-09 16:00:11 +00:00
Cameron Zwarich
a42e5915bf
LoopInstSimplify preserves LoopSimplify.
...
llvm-svn: 123117
2011-01-09 12:35:16 +00:00
Chris Lattner
a337f5ec5c
reduce indentation. Print <nuw> and <nsw> when dumping SCEV AddRec's
...
that have the bit set.
llvm-svn: 123104
2011-01-09 02:16:18 +00:00
Chris Lattner
7d6433ae76
fix a latent bug in memcpyoptimizer that my recent patches exposed: it wasn't
...
updating memdep when fusing stores together. This fixes the crash optimizing
the bullet benchmark.
llvm-svn: 123091
2011-01-08 22:19:21 +00:00
Chris Lattner
ff6ed2ac5f
tryMergingIntoMemset can only handle constant length memsets.
...
llvm-svn: 123090
2011-01-08 22:11:56 +00:00
Chris Lattner
9a1d63ba9f
Merge memsets followed by neighboring memsets and other stores into
...
larger memsets. Among other things, this fixes rdar://8760394 and
allows us to handle "Example 2" from http://blog.regehr.org/archives/320 ,
compiling it into a single 4096-byte memset:
_mad_synth_mute: ## @mad_synth_mute
## BB#0: ## %entry
pushq %rax
movl $4096, %esi ## imm = 0x1000
callq ___bzero
popq %rax
ret
llvm-svn: 123089
2011-01-08 21:19:19 +00:00
Chris Lattner
5120ebf184
fix an issue in IsPointerOffset that prevented us from recognizing that
...
P and P+1 are relative to the same base pointer.
llvm-svn: 123087
2011-01-08 21:07:56 +00:00
Chris Lattner
4dc1fd938f
enhance memcpyopt to merge a store and a subsequent
...
memset into a single larger memset.
llvm-svn: 123086
2011-01-08 20:54:51 +00:00
Chris Lattner
c638147e9f
constify TargetData references.
...
Split memset formation logic out into its own
"tryMergingIntoMemset" helper function.
llvm-svn: 123081
2011-01-08 20:24:01 +00:00
Chris Lattner
59c82f850d
When loop rotation happens, it is *very* common for the duplicated condbr
...
to be foldable into an uncond branch. When this happens, we can make a
much simpler CFG for the loop, which is important for nested loop cases
where we want the outer loop to be aggressively optimized.
Handle this case more aggressively. For example, previously on
phi-duplicate.ll we would get this:
define void @test(i32 %N, double* %G) nounwind ssp {
entry:
%cmp1 = icmp slt i64 1, 1000
br i1 %cmp1, label %bb.nph, label %for.end
bb.nph: ; preds = %entry
br label %for.body
for.body: ; preds = %bb.nph, %for.cond
%j.02 = phi i64 [ 1, %bb.nph ], [ %inc, %for.cond ]
%arrayidx = getelementptr inbounds double* %G, i64 %j.02
%tmp3 = load double* %arrayidx
%sub = sub i64 %j.02, 1
%arrayidx6 = getelementptr inbounds double* %G, i64 %sub
%tmp7 = load double* %arrayidx6
%add = fadd double %tmp3, %tmp7
%arrayidx10 = getelementptr inbounds double* %G, i64 %j.02
store double %add, double* %arrayidx10
%inc = add nsw i64 %j.02, 1
br label %for.cond
for.cond: ; preds = %for.body
%cmp = icmp slt i64 %inc, 1000
br i1 %cmp, label %for.body, label %for.cond.for.end_crit_edge
for.cond.for.end_crit_edge: ; preds = %for.cond
br label %for.end
for.end: ; preds = %for.cond.for.end_crit_edge, %entry
ret void
}
Now we get the much nicer:
define void @test(i32 %N, double* %G) nounwind ssp {
entry:
br label %for.body
for.body: ; preds = %entry, %for.body
%j.01 = phi i64 [ 1, %entry ], [ %inc, %for.body ]
%arrayidx = getelementptr inbounds double* %G, i64 %j.01
%tmp3 = load double* %arrayidx
%sub = sub i64 %j.01, 1
%arrayidx6 = getelementptr inbounds double* %G, i64 %sub
%tmp7 = load double* %arrayidx6
%add = fadd double %tmp3, %tmp7
%arrayidx10 = getelementptr inbounds double* %G, i64 %j.01
store double %add, double* %arrayidx10
%inc = add nsw i64 %j.01, 1
%cmp = icmp slt i64 %inc, 1000
br i1 %cmp, label %for.body, label %for.end
for.end: ; preds = %for.body
ret void
}
With all of these recent changes, we are now able to compile:
void foo(char *X) {
for (int i = 0; i != 100; ++i)
for (int j = 0; j != 100; ++j)
X[j+i*100] = 0;
}
into a single memset of 10000 bytes. This series of changes
should also be helpful for other nested loop scenarios as well.
llvm-svn: 123079
2011-01-08 19:59:06 +00:00
Chris Lattner
30f318e5d1
split ssa updating code out to its own helper function. Don't bother
...
moving the OrigHeader block anymore: we just merge it away anyway so
its code layout doesn't matter.
llvm-svn: 123077
2011-01-08 19:26:33 +00:00
Chris Lattner
2615130e1d
Implement a TODO: Enhance loopinfo to merge away the unconditional branch
...
that it was leaving in loops after rotation (between the original latch
block and the original header.
With this change, it is possible for rotated loops to have just a single
basic block, which is useful.
llvm-svn: 123075
2011-01-08 19:10:28 +00:00
Chris Lattner
930b716e1b
various code cleanups, enhance MergeBlockIntoPredecessor to preserve
...
loop info.
llvm-svn: 123074
2011-01-08 19:08:40 +00:00
Chris Lattner
fee37c5fa3
inline preserveCanonicalLoopForm now that it is simple.
...
llvm-svn: 123073
2011-01-08 18:55:50 +00:00
Chris Lattner
063dca0f6a
Three major changes:
...
1. Rip out LoopRotate's domfrontier updating code. It isn't
needed now that LICM doesn't use DF and it is super complex
and gross.
2. Make DomTree updating code a lot simpler and faster. The
old loop over all the blocks was just to find a block??
3. Change the code that inserts the new preheader to just use
SplitCriticalEdge instead of doing an overcomplex
reimplementation of it.
No behavior change, except for the name of the inserted preheader.
llvm-svn: 123072
2011-01-08 18:52:51 +00:00
Chris Lattner
30d95f9f87
reduce nesting.
...
llvm-svn: 123071
2011-01-08 18:47:43 +00:00
Chris Lattner
7fab23bc1d
LoopRotate requires canonical loop form, so it always has preheaders
...
and latch blocks. Reorder entry conditions to make hte pass faster
and more logical.
llvm-svn: 123069
2011-01-08 18:06:22 +00:00
Chris Lattner
d62691f4e8
use the LI ivar.
...
llvm-svn: 123068
2011-01-08 17:49:51 +00:00
Chris Lattner
385f2ec6d8
some cleanups: remove dead arguments and eliminate ivars
...
that are just passed to one function.
llvm-svn: 123067
2011-01-08 17:48:33 +00:00
Chris Lattner
25ba40a0cc
fix an issue duncan pointed out, which could cause loop rotate
...
to violate LCSSA form
llvm-svn: 123066
2011-01-08 17:38:45 +00:00
Cameron Zwarich
b4ab257bcc
Fix coding style issues.
...
llvm-svn: 123065
2011-01-08 17:07:11 +00:00
Cameron Zwarich
84986b298a
Make more passes preserve dominators (or state that they preserve dominators if
...
they all ready do). This removes two dominator recomputations prior to isel,
which is a 1% improvement in total llc time for 403.gcc.
The only potentially suspect thing is making GCStrategy recompute dominators if
it used a custom lowering strategy.
llvm-svn: 123064
2011-01-08 17:01:52 +00:00
Cameron Zwarich
80bd9af7c5
Contract subloop bodies. However, it is still important to visit the phis at the
...
top of subloop headers, as the phi uses logically occur outside of the subloop.
llvm-svn: 123062
2011-01-08 15:52:22 +00:00
Frits van Bommel
6a1fb8f235
Fix a bug in r123034 (trying to sext/zext non-integers) and clean up a little.
...
llvm-svn: 123061
2011-01-08 10:51:36 +00:00
Chris Lattner
8c5defd0b0
Have loop-rotate simplify instructions (yay instsimplify!) as it clones
...
them into the loop preheader, eliminating silly instructions like
"icmp i32 0, 100" in fixed tripcount loops. This also better exposes the
bigger problem with loop rotate that I'd like to fix: once this has been
folded, the duplicated conditional branch *often* turns into an uncond branch.
Not aggressively handling this is pessimizing later loop optimizations
somethin' fierce by making "dominates all exit blocks" checks fail.
llvm-svn: 123060
2011-01-08 08:24:46 +00:00
Chris Lattner
43f8d16482
Revamp the ValueMapper interfaces in a couple ways:
...
1. Take a flags argument instead of a bool. This makes
it more clear to the reader what it is used for.
2. Add a flag that says that "remapping a value not in the
map is ok".
3. Reimplement MapValue to share a bunch of code and be a lot
more efficient. For lookup failures, don't drop null values
into the map.
4. Using the new flag a bunch of code can vaporize in LinkModules
and LoopUnswitch, kill it.
No functionality change.
llvm-svn: 123058
2011-01-08 08:15:20 +00:00
Chris Lattner
2b3f20e6ec
two minor changes: switch to the standard ValueToValueMapTy
...
map from ValueMapper.h (giving us access to its utilities)
and add a fastpath in the loop rotation code, avoiding expensive
ssa updator manipulation for values with nothing to update.
llvm-svn: 123057
2011-01-08 07:21:31 +00:00
Tobias Grosser
fc3d7f664b
InstCombine: Match min/max hidden by sext/zext
...
X = sext x; x >s c ? X : C+1 --> X = sext x; X <s C+1 ? C+1 : X
X = sext x; x <s c ? X : C-1 --> X = sext x; X >s C-1 ? C-1 : X
X = zext x; x >u c ? X : C+1 --> X = zext x; X <u C+1 ? C+1 : X
X = zext x; x <u c ? X : C-1 --> X = zext x; X >u C-1 ? C-1 : X
X = sext x; x >u c ? X : C+1 --> X = sext x; X <u C+1 ? C+1 : X
X = sext x; x <u c ? X : C-1 --> X = sext x; X >u C-1 ? C-1 : X
Instead of calculating this with mixed types promote all to the
larger type. This enables scalar evolution to analyze this
expression. PR8866
llvm-svn: 123034
2011-01-07 21:33:14 +00:00
Tobias Grosser
411e6eedff
Some whitespace fixes
...
llvm-svn: 123033
2011-01-07 21:33:13 +00:00
Benjamin Kramer
134cde912a
Revert 122959, it needs more thought. Add it back to README.txt with additional notes.
...
llvm-svn: 123030
2011-01-07 20:42:20 +00:00
Jay Foad
89afb43b1e
Remove all uses of the "ugly" method BranchInst::setUnconditionalDest().
...
llvm-svn: 123025
2011-01-07 20:25:56 +00:00
Benjamin Kramer
ae67cc13a9
InstCombine: Turn _chk functions into the "unsafe" variant if length and max langth are equal.
...
This happens when we take the (non-constant) length from a malloc.
llvm-svn: 122961
2011-01-06 14:22:52 +00:00
Benjamin Kramer
799b011276
InstCombine: If we call llvm.objectsize on a malloc call we can replace it with the size passed to malloc.
...
llvm-svn: 122959
2011-01-06 13:11:05 +00:00
Benjamin Kramer
a76cc117e0
InstCombine: Teach llvm.objectsize folding to look through GEPs.
...
llvm-svn: 122958
2011-01-06 13:07:49 +00:00
Cameron Zwarich
9ec19ea06a
Add the CallInst optimizations that don't involve expanding inline assembly to
...
OptimizeInst() so that they can be used on a worklist instruction.
llvm-svn: 122945
2011-01-06 02:56:42 +00:00
Cameron Zwarich
d28c78eb4f
Move the GEP handling in CodeGenPrepare to OptimizeInst().
...
llvm-svn: 122944
2011-01-06 02:44:52 +00:00
Cameron Zwarich
14ac865ca9
Split the optimizations in CodeGenPrepare that don't manipulate the iterators
...
into a separate function, so that it can be called from a loop using a worklist
rather than a loop traversing a whole basic block.
llvm-svn: 122943
2011-01-06 02:37:26 +00:00
Jakob Stoklund Olesen
70be93a200
Zap the last two -Wself-assign warnings in llvm.
...
Simplify RALinScan::DowngradeRegister with TRI::getOverlaps while we are there.
llvm-svn: 122940
2011-01-06 01:33:22 +00:00
Cameron Zwarich
ce3b930a98
Stop reallocating SunkAddrs for each basic block. When we move to an instruction
...
worklist, the key will need to become std::pair<BasicBlock*, Value*>.
llvm-svn: 122932
2011-01-06 00:42:50 +00:00
Cameron Zwarich
b62ccb241b
Add some more statistics to CodeGenPrepare.
...
llvm-svn: 122891
2011-01-05 17:47:38 +00:00
Cameron Zwarich
ced753fadf
Add some stats to CodeGenPrepare to make it easier to speed it up without
...
regressing code quality.
llvm-svn: 122887
2011-01-05 17:27:27 +00:00
Cameron Zwarich
6a78995369
Use pop_back_val instead of back followed by pop_back.
...
llvm-svn: 122876
2011-01-05 16:08:47 +00:00
Cameron Zwarich
5a2bb998ac
Use a worklist for later iterations just like ordinary instsimplify. The next
...
step is to only process instructions in subloops if they have been modified by
an earlier simplification.
llvm-svn: 122869
2011-01-05 05:47:47 +00:00
Cameron Zwarich
4c51d122d5
Change LoopInstSimplify back to a LoopPass. It revisits subloops rather than
...
skipping them, but it should probably use a worklist and only revisit those
instructions in subloops that have actually changed. It should probably also
use a worklist after the first iteration like instsimplify now does. Regardless,
it's only 0.3% of opt -O2 time on 403.gcc if it replaces the instcombine placed
in the middle of the loop passes.
llvm-svn: 122868
2011-01-05 05:15:53 +00:00
Owen Anderson
7b25ff04bd
Don't bother value numbering instructions with void types in GVN. In theory this should allow us to insert
...
fewer things into the value numbering maps, but any speedup is beneath the noise threshold on my machine
on 403.gcc.
llvm-svn: 122844
2011-01-04 22:15:21 +00:00
Owen Anderson
e39cb57b09
Complete the NumberTable --> LeaderTable rename.
...
llvm-svn: 122828
2011-01-04 19:29:46 +00:00
Owen Anderson
d7d06d3aaf
Fix typo in a comment.
...
llvm-svn: 122827
2011-01-04 19:25:18 +00:00
Owen Anderson
51489b3b28
Prune #include's.
...
llvm-svn: 122826
2011-01-04 19:24:57 +00:00
Owen Anderson
c7c3bc63f7
Clarify terminology, settling on referring to what was the "number table" as the "leader table", and
...
rename methods to make it much more clear what they're doing.
llvm-svn: 122823
2011-01-04 19:13:25 +00:00
Owen Anderson
83546f2fe0
When removing a value from GVN's leaders list, don't drop the Next pointer in a corner case.
...
llvm-svn: 122822
2011-01-04 19:10:54 +00:00
Dale Johannesen
a71d2cc88d
Improve the accuracy of the inlining heuristic looking for the
...
case where a static caller is itself inlined everywhere else, and
thus may go away if it doesn't get too big due to inlining other
things into it. If there are references to the caller other than
calls, it will not be removed; account for this.
This results in same-day completion of the case in PR8853.
llvm-svn: 122821
2011-01-04 19:01:54 +00:00
Owen Anderson
41a1550ef5
Branch instructions don't produce values, so there's no need to generate a value number for them. This
...
avoids adding them to the various value numbering tables, resulting in a minor (~3%) speedup for GVN
on 40.gcc.
llvm-svn: 122819
2011-01-04 18:54:18 +00:00
Owen Anderson
22c53e277a
Remove commented out code.
...
llvm-svn: 122817
2011-01-04 18:22:08 +00:00
Cameron Zwarich
b2a41e9388
Switch to the new style of asterisk placement.
...
llvm-svn: 122815
2011-01-04 18:19:19 +00:00
Chris Lattner
8643810ede
Teach loop-idiom to turn a loop containing a memset into a larger memset
...
when safe.
The testcase is basically this nested loop:
void foo(char *X) {
for (int i = 0; i != 100; ++i)
for (int j = 0; j != 100; ++j)
X[j+i*100] = 0;
}
which gets turned into a single memset now. clang -O3 doesn't optimize
this yet though due to a phase ordering issue I haven't analyzed yet.
llvm-svn: 122806
2011-01-04 07:46:33 +00:00
Chris Lattner
a62b01dc37
restructure this a bit. Initialize the WeakVH with "I", the
...
instruction *after* the store. The store will always be deleted
if the transformation kicks in, so we'd do an N^2 scan of every
loop block. Whoops.
llvm-svn: 122805
2011-01-04 07:27:30 +00:00
Cameron Zwarich
f4e13699e7
Avoid finding loop back edges when we are not splitting critical edges in
...
CodeGenPrepare (which is the default behavior).
llvm-svn: 122801
2011-01-04 04:43:31 +00:00
Cameron Zwarich
e924969380
Address most of Duncan's review comments. Also, make LoopInstSimplify a simple
...
FunctionPass. It probably doesn't have a reason to be a LoopPass, as it will
probably drop the simple fixed point and either use RPO iteration or Duncan's
approach in instsimplify of only revisiting instructions that have changed.
The next step is to preserve LoopSimplify. This looks like it won't be too hard,
although the pass manager doesn't actually seem to respect when non-loop passes
claim to preserve LCSSA or LoopSimplify. This will have to be fixed.
llvm-svn: 122791
2011-01-04 00:12:46 +00:00
Chris Lattner
0ba473c218
use the very-handy getTruncateOrZeroExtend helper function, and
...
stop setting NSW: signed overflow is possible. Thanks to Dan
for pointing these out.
llvm-svn: 122790
2011-01-04 00:06:55 +00:00
Owen Anderson
0839d3930a
Fix comment.
...
llvm-svn: 122788
2011-01-03 23:51:56 +00:00
Owen Anderson
d62d37225a
Use the new addEscapingValue callback to update GlobalsModRef when GVN adds PHIs of GEPs. For the moment,
...
have GlobalsModRef handle this conservatively by simply removing the value from its maps.
llvm-svn: 122787
2011-01-03 23:51:43 +00:00
Chris Lattner
bde6ec1db6
Duncan deftly points out that readnone functions aren't
...
invalidated by stores, so they can be handled as 'simple'
operations.
llvm-svn: 122785
2011-01-03 23:38:13 +00:00
Owen Anderson
3a33d0cc4a
Simplify GVN's value expression structure, allowing the elimination of a lot of
...
almost-but-not-quite-identical code. No intended functionality change.
llvm-svn: 122760
2011-01-03 19:00:11 +00:00
Chris Lattner
16ca19ffc5
stength reduce my previous patch a bit. The only instructions
...
that are allowed to have metadata operands are intrinsic calls,
and the only ones that take metadata currently return void.
Just reject all void instructions, which should not be value
numbered anyway. To future proof things, add an assert to the
getHashValue impl for calls to check that metadata operands
aren't present.
llvm-svn: 122759
2011-01-03 18:43:03 +00:00
Chris Lattner
142f1cd251
fix PR8895: metadata operands don't have a strong use of their
...
nested values, so they can change and drop to null, which can
change the hash and cause havok.
It turns out that it isn't a good idea to value number stuff
with metadata operands anyway, so... don't.
llvm-svn: 122758
2011-01-03 18:28:15 +00:00
Duncan Sands
697de77339
Speed up instsimplify by about 10-15% by not bothering to retry
...
InstructionSimplify on instructions that didn't change since the
last time round the loop.
llvm-svn: 122745
2011-01-03 10:50:04 +00:00
Cameron Zwarich
43cecb1200
Switch a worklist in CodeGenPrepare to SmallVector and increase the inline
...
capacity on the Visited SmallPtrSet. On 403.gcc, this is about a 4.5% speedup of
CodeGenPrepare time (which itself is 10% of time spent in the backend).
This is progress towards PR8889.
llvm-svn: 122741
2011-01-03 06:33:01 +00:00
Chris Lattner
9e5e9ed79a
earlycse can do trivial with-a-block dead store
...
elimination as well. This deletes 60 stores in 176.gcc
that largely come from bitfield code.
llvm-svn: 122736
2011-01-03 04:17:24 +00:00
Chris Lattner
4b9a525742
switch the load table to use a recycling bump pointer allocator,
...
speeding earlycse up by 6%.
llvm-svn: 122733
2011-01-03 03:53:50 +00:00
Chris Lattner
e0e32a9ef0
now that loads are in their own table, we can implement
...
store->load forwarding. This allows EarlyCSE to zap 600 more
loads from 176.gcc.
llvm-svn: 122732
2011-01-03 03:46:34 +00:00
Chris Lattner
92bb0f9f9d
split loads and calls into separate tables. Loads are now just indexed
...
by their pointer instead of using MemoryValue to wrap it.
llvm-svn: 122731
2011-01-03 03:41:27 +00:00
Chris Lattner
4cb365414f
various cleanups, no functionality change.
...
llvm-svn: 122729
2011-01-03 03:28:23 +00:00
Chris Lattner
b9a8efc960
Teach EarlyCSE to do trivial CSE of loads and read-only calls.
...
On 176.gcc, this catches 13090 loads and calls, and increases the
number of simple instructions CSE'd from 29658 to 36208.
llvm-svn: 122727
2011-01-03 03:18:43 +00:00
Chris Lattner
79d83067ee
rename InstValue to SimpleValue, add some comments.
...
llvm-svn: 122725
2011-01-03 02:20:48 +00:00
Michael J. Spencer
edb5bcdde5
CMake: Add missing source file.
...
llvm-svn: 122724
2011-01-03 02:13:05 +00:00
Chris Lattner
d815f69b30
Allocate nodes for the scoped hash table from a recyling bump pointer
...
allocator. This speeds up early cse by about 20%
llvm-svn: 122723
2011-01-03 01:42:46 +00:00
Chris Lattner
02a9776b64
reduce redundancy in the hashing code and other misc cleanups.
...
llvm-svn: 122720
2011-01-03 01:10:08 +00:00
Cameron Zwarich
cab9a0abab
Add a new loop-instsimplify pass, with the intention of replacing the instance
...
of instcombine that is currently in the middle of the loop pass pipeline. This
commit only checks in the pass; it will hopefully be enabled by default later.
llvm-svn: 122719
2011-01-03 00:25:16 +00:00
Chris Lattner
0844c76f9a
fix some pastos
...
llvm-svn: 122718
2011-01-02 23:29:58 +00:00
Chris Lattner
8fac5db251
add DEBUG and -stats output to earlycse.
...
Teach it to CSE the rest of the non-side-effecting instructions.
llvm-svn: 122716
2011-01-02 23:19:45 +00:00
Chris Lattner
18ae5436b1
Enhance earlycse to do CSE of casts, instsimplify and die.
...
Add a testcase.
llvm-svn: 122715
2011-01-02 23:04:14 +00:00
Chris Lattner
bf0aa927cc
split dom frontier handling stuff out to its own DominanceFrontier header,
...
so that Dominators.h is *just* domtree. Also prune #includes a bit.
llvm-svn: 122714
2011-01-02 22:09:33 +00:00
Chris Lattner
704541bb23
sketch out a new early cse pass. No functionality yet.
...
llvm-svn: 122713
2011-01-02 21:47:05 +00:00
Chris Lattner
9c69406f2b
fix a miscompilation of tramp3d-v4: when forming a memcpy, we have to make
...
sure that the loop we're promoting into a memcpy doesn't mutate the input
of the memcpy. Before we were just checking that the dest of the memcpy
wasn't mod/ref'd by the loop.
llvm-svn: 122712
2011-01-02 21:14:18 +00:00
Chris Lattner
5702a43c09
If a loop iterates exactly once (has backedge count = 0) then don't
...
mess with it. We'd rather peel/unroll it than convert all of its
stores into memsets.
llvm-svn: 122711
2011-01-02 20:24:21 +00:00
Nick Lewycky
5361b84184
Also remove functions that use complex constant expressions in terms of
...
another function.
llvm-svn: 122705
2011-01-02 19:16:44 +00:00
Chris Lattner
8455b6e45e
enhance loop idiom recognition to scan *all* unconditionally executed
...
blocks in a loop, instead of just the header block. This makes it more
aggressive, able to handle Duncan's Ada examples.
llvm-svn: 122704
2011-01-02 19:01:03 +00:00
Chris Lattner
0cdc6f62a5
make inSubLoop much more efficient.
...
llvm-svn: 122703
2011-01-02 18:53:08 +00:00
Chris Lattner
27497ece96
rip out isExitBlockDominatedByBlockInLoop, calling DomTree::dominates instead.
...
isExitBlockDominatedByBlockInLoop is a relic of the days when domtree was
*just* a tree and didn't have DFS numbers. Checking DFS numbers is faster
and easier than "limiting the search of the tree".
llvm-svn: 122702
2011-01-02 18:45:39 +00:00
Chris Lattner
0469e01c02
add a list of opportunities for future improvement.
...
llvm-svn: 122701
2011-01-02 18:32:09 +00:00
Duncan Sands
64f1c0dcda
Fix PR8702 by not having LoopSimplify claim to preserve LCSSA form. As described
...
in the PR, the pass could break LCSSA form when inserting preheaders. It probably
would be easy enough to fix this, but since currently we always go into LCSSA form
after running this pass, doing so is not urgent.
llvm-svn: 122695
2011-01-02 13:38:21 +00:00
Chris Lattner
ddf58010bd
Allow loop-idiom to run on multiple BB loops, but still only scan the loop
...
header for now for memset/memcpy opportunities. It turns out that loop-rotate
is successfully rotating loops, but *DOESN'T MERGE THE BLOCKS*, turning "for
loops" into 2 basic block loops that loop-idiom was ignoring.
With this fix, we form many *many* more memcpy and memsets than before, including
on the "history" loops in the viterbi benchmark, which look like this:
for (j=0; j<MAX_history; ++j) {
history_new[i][j+1] = history[2*i][j];
}
Transforming these loops into memcpy's speeds up the viterbi benchmark from
11.98s to 3.55s on my machine. Woo.
llvm-svn: 122685
2011-01-02 07:58:36 +00:00
Chris Lattner
5b5a043d82
remove debugging code.
...
llvm-svn: 122683
2011-01-02 07:37:13 +00:00
Chris Lattner
12f91befce
add some -stats output.
...
llvm-svn: 122682
2011-01-02 07:36:44 +00:00
Chris Lattner
679572e584
improve loop rotation to use CodeMetrics to analyze the
...
size of a loop header instead of its own code size estimator.
This allows it to handle bitcasts etc more precisely.
llvm-svn: 122681
2011-01-02 07:35:53 +00:00
Chris Lattner
85b6d81d41
teach loop idiom recognition to form memcpy's from simple loops.
...
llvm-svn: 122678
2011-01-02 03:37:56 +00:00
Nick Lewycky
4e250c8245
Remove functions from the FnSet when one of their callee's is being merged. This
...
maintains the guarantee that the DenseSet expects two elements it contains to
not go from inequal to equal under its nose.
As a side-effect, this also lets us switch from iterating to a fixed-point to
actually maintaining a work queue of functions to look at again, and we don't
add thunks to our work queue so we don't need to detect and ignore them.
llvm-svn: 122677
2011-01-02 02:46:33 +00:00
Chris Lattner
1903c42b97
fix a globalopt crash on two Adobe-C++ testcases that the recent
...
loop idiom pass exposed.
llvm-svn: 122674
2011-01-01 22:31:46 +00:00
Chris Lattner
a3514441e0
add a validity check that was missed, fixing a crash on the
...
new testcase.
llvm-svn: 122662
2011-01-01 20:12:04 +00:00
Chris Lattner
91a4435875
improve validity check to handle constant-trip-count loops more
...
aggressively. In practice, this doesn't help anything though,
see the todo.
llvm-svn: 122660
2011-01-01 19:54:22 +00:00
Chris Lattner
8b3baf6d75
implement the "no aliasing accesses in loop" safety check. This pass
...
should be correct now.
llvm-svn: 122659
2011-01-01 19:39:01 +00:00
Duncan Sands
2c440fa403
Simplify this pass by using a depth-first iterator to ensure that all
...
operands are visited before the instructions themselves.
llvm-svn: 122647
2010-12-31 17:49:05 +00:00
Duncan Sands
6cc7126ed9
Zap dead instructions harder.
...
llvm-svn: 122645
2010-12-31 16:17:54 +00:00
Benjamin Kramer
570dd787a6
Make a bunch of symbols internal.
...
llvm-svn: 122642
2010-12-30 22:34:44 +00:00
Chris Lattner
65a699d4d0
simplify this, isBytewiseValue handles the extra check. We still
...
check for "multiple of a byte" in size to make it clear that the
>> 3 below is safe.
llvm-svn: 122604
2010-12-28 18:53:48 +00:00
Duncan Sands
5cf10e691b
Silence gcc warning about an unused variable when doing a release build.
...
llvm-svn: 122593
2010-12-28 09:41:15 +00:00
Chris Lattner
cb18bfa3d2
fix some issues Frits noticed, add AliasAnalysis as a dependency
...
llvm-svn: 122585
2010-12-27 18:39:08 +00:00
Benjamin Kramer
84bd73c527
BuildLibCalls: Nuke EmitMemCpy, EmitMemMove and EmitMemSet. They are dead and superseded by IRBuilder.
...
llvm-svn: 122576
2010-12-27 00:25:32 +00:00
Benjamin Kramer
7cba269dfb
SimplifyLibCalls: Use IRBuilder to simplify code.
...
llvm-svn: 122575
2010-12-27 00:16:46 +00:00
Chris Lattner
b9fe685b9a
have loop-idiom nuke instructions that feed stores that get removed.
...
llvm-svn: 122574
2010-12-27 00:03:23 +00:00
Chris Lattner
29e14edc8d
implement enough of the memset inference algorithm to recognize and insert
...
memsets. This is still missing one important validity check, but this is enough
to compile stuff like this:
void test0(std::vector<char> &X) {
for (std::vector<char>::iterator I = X.begin(), E = X.end(); I != E; ++I)
*I = 0;
}
void test1(std::vector<int> &X) {
for (long i = 0, e = X.size(); i != e; ++i)
X[i] = 0x01010101;
}
With:
$ clang t.cpp -S -o - -O2 -emit-llvm | opt -loop-idiom | opt -O3 | llc
to:
__Z5test0RSt6vectorIcSaIcEE: ## @_Z5test0RSt6vectorIcSaIcEE
## BB#0: ## %entry
subq $8, %rsp
movq (%rdi), %rax
movq 8(%rdi), %rsi
cmpq %rsi, %rax
je LBB0_2
## BB#1: ## %bb.nph
subq %rax, %rsi
movq %rax, %rdi
callq ___bzero
LBB0_2: ## %for.end
addq $8, %rsp
ret
...
__Z5test1RSt6vectorIiSaIiEE: ## @_Z5test1RSt6vectorIiSaIiEE
## BB#0: ## %entry
subq $8, %rsp
movq (%rdi), %rax
movq 8(%rdi), %rdx
subq %rax, %rdx
cmpq $4, %rdx
jb LBB1_2
## BB#1: ## %for.body.preheader
andq $-4, %rdx
movl $1, %esi
movq %rax, %rdi
callq _memset
LBB1_2: ## %for.end
addq $8, %rsp
ret
llvm-svn: 122573
2010-12-26 23:42:51 +00:00
Chris Lattner
6cf8d6cc6e
start using irbuilder to make mem intrinsics in a few passes.
...
llvm-svn: 122572
2010-12-26 22:57:41 +00:00
Chris Lattner
7c5f9c35d1
sketch more of this out.
...
llvm-svn: 122567
2010-12-26 20:45:45 +00:00
Chris Lattner
9cb1035f94
move isBytewiseValue out to ValueTracking.h/cpp
...
llvm-svn: 122565
2010-12-26 20:15:01 +00:00
Chris Lattner
81ae3f299a
actually add the file...
...
llvm-svn: 122563
2010-12-26 19:39:38 +00:00
Chris Lattner
2ef535a4e4
Start of a pass for recognizing memset and memcpy idioms.
...
No functionality yet.
llvm-svn: 122562
2010-12-26 19:32:44 +00:00
Benjamin Kramer
30342fb1fd
Simplify code.
...
llvm-svn: 122561
2010-12-26 15:23:45 +00:00
Chris Lattner
d729d0dcdb
don't lose TD info
...
llvm-svn: 122556
2010-12-25 20:52:04 +00:00
Chris Lattner
20fca48341
switch the inliner alignment enforcement stuff to use the
...
getOrEnforceKnownAlignment function, which simplifies the code
and makes it stronger.
llvm-svn: 122555
2010-12-25 20:42:38 +00:00
Chris Lattner
6fcd32e7d7
Move getOrEnforceKnownAlignment out of instcombine into Transforms/Utils.
...
llvm-svn: 122554
2010-12-25 20:37:57 +00:00
Benjamin Kramer
b90b2f0635
Fix a thinko pointed out by Frits van Bommel: looking through global variables in isBytewiseValue is not safe.
...
llvm-svn: 122550
2010-12-24 22:23:59 +00:00
Benjamin Kramer
ea9152e551
MemCpyOpt: Turn memcpys from a constant into a memset if possible.
...
This allows us to compile "int cst[] = {-1, -1, -1};" into
movl $-1, 16(%rsp)
movq $-1, 8(%rsp)
instead of
movl _cst+8(%rip), %eax
movl %eax, 16(%rsp)
movq _cst(%rip), %rax
movq %rax, 8(%rsp)
llvm-svn: 122548
2010-12-24 21:17:12 +00:00
Owen Anderson
226ac14afb
When determining if we can fold (x >> C1) << C2, the bits that we need to verify are zero
...
are not the low bits of x, but the bits that WILL be the low bits after the operation completes.
llvm-svn: 122529
2010-12-23 23:56:24 +00:00
Owen Anderson
5d690d4168
It is possible for SimplifyCFG to cause PHI nodes to become redundant too late in the optimization
...
pipeline to be caught by instcombine, and it's not feasible to catch them in SimplifyCFG because the
use-lists are in an inconsistent state at the point where it could know that it need to simplify them.
Instead, have CodeGenPrepare look for trivially redundant PHIs as part of its general cleanup effort.
llvm-svn: 122516
2010-12-23 20:57:35 +00:00
Mon P Wang
18b762a946
Preserve the address space when generating bitcasts for MemTransferInst in ConvertToScalarInfo
...
llvm-svn: 122462
2010-12-23 01:41:32 +00:00
Jeffrey Yasskin
9b43f33620
Change all self assignments X=X to (void)X, so that we can turn on a
...
new gcc warning that complains on self-assignments and
self-initializations.
llvm-svn: 122458
2010-12-23 00:58:24 +00:00
Benjamin Kramer
8ef5001b27
InstCombine: creating selects from -1 and 0 is fine, they combine into a sext from i1.
...
llvm-svn: 122453
2010-12-22 23:12:15 +00:00
Duncan Sands
fbb9ac3cca
Add a generic expansion transform: A op (B op' C) -> (A op B) op' (A op C)
...
if both A op B and A op C simplify. This fires fairly often but doesn't
make that much difference. On gcc-as-one-file it removes two "and"s and
turns one branch into a select.
llvm-svn: 122399
2010-12-22 13:36:08 +00:00
Duncan Sands
3547d2ebd8
Add some statistics, good for understanding how much more powerful
...
instcombine is compared to instsimplify.
llvm-svn: 122397
2010-12-22 09:40:51 +00:00
Owen Anderson
5ab8d4b5e5
Give GVN back the ability to perform simple conditional propagation on conditional branch values.
...
I still think that LVI should be handling this, but that capability is some ways off in the future,
and this matters for some significant benchmarks.
llvm-svn: 122378
2010-12-21 23:54:34 +00:00
Owen Anderson
12470778d7
Remove dead code.
...
llvm-svn: 122371
2010-12-21 22:31:24 +00:00
Benjamin Kramer
43493c089f
GVN's Expression is not POD-like (it contains a SmallVector). Simplify code while at it.
...
llvm-svn: 122362
2010-12-21 21:30:19 +00:00
Duncan Sands
3b8af41a3e
Visit instructions deterministically. Use a FIFO so as to approximately
...
visit instructions before their uses, since InstructionSimplify does a
better job in that case. All this prompted by Frits van Bommel.
llvm-svn: 122343
2010-12-21 17:08:55 +00:00
Duncan Sands
e7cbb64ec0
If an instruction simplifies, try again to simplify any uses of it. This is
...
not very important since the pass is only used for testing, but it does make
it more realistic. Suggested by Frits van Bommel.
llvm-svn: 122336
2010-12-21 16:12:03 +00:00
Duncan Sands
d0eb6d39f8
Pull a few more simplifications out of instcombine (there are still
...
plenty left though!), in particular for multiplication.
llvm-svn: 122330
2010-12-21 14:00:22 +00:00
Duncan Sands
eaff500c7b
Oops, forgot to add the pass itself!
...
llvm-svn: 122265
2010-12-20 21:07:42 +00:00
Duncan Sands
a436cbe4bf
Add a new convenience pass for testing InstructionSimplify. Previously
...
it could only be tested indirectly, via instcombine, gvn or some other
pass that makes use of InstructionSimplify, which means that testcases
had to be carefully contrived to dance around any other transformations
that that pass did.
llvm-svn: 122264
2010-12-20 20:54:37 +00:00
Benjamin Kramer
f7957d0463
Add a check missing from my last commit and avoid a potential overflow situation.
...
llvm-svn: 122258
2010-12-20 20:00:31 +00:00
Benjamin Kramer
2bca3a67b3
Reduce indentation.
...
llvm-svn: 122249
2010-12-20 16:21:59 +00:00
Benjamin Kramer
68531baea9
Teach InstCombine to merge (icmp ult (X + CA), C1) | (icmp eq X, C2) into (icmp ult (X + CA), C1 + 1) if C2 + CA == C1.
...
InstCombine creates these so now we compile x == 23 || x == 24 || x == 25 to
%x.off = add i32 %x, -23
%1 = icmp ult i32 %x.off, 3
instead of
%x.off = add i32 %x, -23
%1 = icmp ult i32 %x.off, 2
%cmp3 = icmp eq i32 %x, 25
%ret2 = or i1 %1, %cmp3
llvm-svn: 122248
2010-12-20 16:18:51 +00:00
Chris Lattner
27ca8ebd4b
fix PR8807 by making transformConstExprCastCall aware of byval arguments.
...
llvm-svn: 122238
2010-12-20 08:36:38 +00:00
Chris Lattner
7398965b67
various cleanups for transformConstExprCastCall
...
llvm-svn: 122237
2010-12-20 08:25:06 +00:00
Chris Lattner
0f11495289
when eliding a byval copy due to inlining a readonly function, we have
...
to make sure that the reused alloca has sufficient alignment.
llvm-svn: 122236
2010-12-20 08:10:40 +00:00
Chris Lattner
0099744506
pull byval processing out to its own helper function.
...
llvm-svn: 122235
2010-12-20 07:57:41 +00:00
Chris Lattner
7394680a00
fix PR8769, a miscompilation by inliner when inlining a function with a byval
...
argument. The generated alloca has to have at least the alignment of the
byval, if not, the client may be making assumptions that the new alloca won't
satisfy.
llvm-svn: 122234
2010-12-20 07:45:28 +00:00
Mon P Wang
1991c47ec1
Avoid dropping the address space when InstCombine optimizes memset
...
llvm-svn: 122215
2010-12-20 01:05:30 +00:00
Chris Lattner
4fb9dd4c74
fix an oversight caught by Frits!
...
llvm-svn: 122204
2010-12-19 23:24:04 +00:00
Chris Lattner
b6252a376a
tidy up
...
llvm-svn: 122190
2010-12-19 20:24:28 +00:00
Chris Lattner
3e635d2e99
move a transformation to a more logical place, simplifying it.
...
llvm-svn: 122183
2010-12-19 19:43:52 +00:00
Chris Lattner
5e0c0c72e9
recognize an unsigned add with overflow idiom into uadd.
...
This resolves a README entry and technically resolves PR4916,
but we still get poor code for the testcase in that PR because
GVN isn't CSE'ing uadd with add, filed as PR8817.
Previously we got:
_test7: ## @test7
addq %rsi, %rdi
cmpq %rdi, %rsi
movl $42, %eax
cmovaq %rsi, %rax
ret
Now we get:
_test7: ## @test7
addq %rsi, %rdi
movl $42, %eax
cmovbq %rsi, %rax
ret
llvm-svn: 122182
2010-12-19 19:37:52 +00:00