Commit Graph

1967 Commits

Author SHA1 Message Date
Nick Lewycky
0f8df9a9ce Run a post-pass that marks known function declarations by name.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61632 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-04 20:27:34 +00:00
Bill Wendling
a96658c417 XFAIL this test. The xform was removed.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61624 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-04 06:32:28 +00:00
Duncan Sands
338cd6ba6e When calculating 'nocapture' argument attributes, allow
the argument to be stored to an alloca by tracking uses
of the alloca.  This occurs 4 times (out of 7121, 0.05%)
in MultiSource/Applications, so may not be worth it.  On
the other hand, it is easy to do and fairly cheap.  The
functions it helps are: W_addcom and W_addlit in spiff;
process_args (argv) in d (make_dparser); ercPixConcealIMB
in JM/ldecod.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61570 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-02 11:54:37 +00:00
Chris Lattner
df98617b23 Reimplement the old and horrible bison parser for .ll files with a nice
and clean recursive descent parser.

This change has a couple of ramifications:
1. The parser code is about 400 lines shorter (in what we maintain, not
   including what is autogenerated).
2. The code should be significantly faster than the old code because we 
   don't have to work around bison's poor handling of datatypes with 
   ctors/dtors.  This also makes the code much more resistant to memory 
   leaks.
3. We now get caret diagnostics from the .ll parser, woo.
4. The actual diagnostics emited from the parser are completely different
   so a bunch of testcases had to be updated.
5. I now disallow "%ty = type opaque %ty = type i32".  There was no good
   reason to support this, it was just an accident of the old 
   implementation.  I have no reason to think that anyone is actually using
   this.
6. The syntax for sticking a global variable has changed to make it 
   unambiguous.  I don't think anyone is depending on this since only clang
   supports this and it is not solid yet, so I'm not worried about anything
   breaking.
7. This gets rid of the last use of bison, and along with it the .cvs files.
   I'll prune this from the makefiles as a subsequent commit.

There are a few minor cleanups that can be done after this commit (suggestions
welcome!) but this passes dejagnu testing and is ready for its time in the
limelight.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61558 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-02 07:01:27 +00:00
Nick Lewycky
8439653dfc Remove the cyclic part of this test, it was passing for the wrong
reason. Two functions which mutually require each other to be nocapture 
are not currently supported.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61553 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-02 03:52:27 +00:00
Nick Lewycky
6b05686283 Make adding nocapture a bit stronger. FreeInst is nocapture. Also,
functions that don't write can't leak a pointer except through 
the return value, so a void readonly function is implicitly nocapture.

Test these, and add a test that verifies that f1 calling f2 with an 
otherwise dead pointer gets both of them marked nocapture.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61552 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-02 03:46:56 +00:00
Duncan Sands
29ab02b2c2 Add tests for two types of traps that escape analysis
might one day fall into.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61549 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-02 00:55:51 +00:00
Bill Wendling
3479be91c4 Add transformation:
xor (or (icmp, icmp), true) -> and(icmp, icmp)

This is possible because of De Morgan's law.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61537 91177308-0d34-0410-b5e6-96231b3b80d8
2009-01-01 01:18:23 +00:00
Duncan Sands
1010941954 Look through phi nodes and select instructions when
calculating nocapture attributes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61535 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-31 20:21:34 +00:00
Duncan Sands
9e89ba31f1 Rename AddReadAttrs to FunctionAttrs, and teach it how
to work out (in a very simplistic way) which function
arguments (pointer arguments only) are only dereferenced
and so do not escape.  Mark such arguments 'nocapture'.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61525 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-31 16:14:43 +00:00
Duncan Sands
516ec62bfe Allow readnone functions to read (and write!) global
constants, since doing so is irrelevant for aliasing
purposes.  While this doesn't increase the total number
of functions marked readonly or readnone in MultiSource/
Applications (3089), it does result in 12 functions being
marked readnone rather than readonly.
Before:
  readnone: 820
  readonly: 2269
After:
  readnone: 832
  readonly: 2257


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61469 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-29 11:34:09 +00:00
Nick Lewycky
13a09e298c Turn strcmp into memcmp, such as strcmp(P, "x") --> memcmp(P, "x", 2).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61297 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-21 00:19:21 +00:00
Nick Lewycky
2a8f6597a3 Make all the vector elements positive in an srem of constant vector.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61195 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-18 06:31:11 +00:00
Chris Lattner
bce4afe839 Enhance heap sra to be substantially more aggressive w.r.t PHI
nodes.  This allows it to do fairly general phi insertion if a 
load from a pointer global wants to be SRAd but the load is used
by (recursive) phi nodes.  This fixes a pessimization on ppc
introduced by Load PRE.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61123 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-17 05:28:49 +00:00
Chris Lattner
85d3d4f35d Fix another crash found by inspection. If we have a PHI node merging
the load multiple times, make sure the check the uses of the PHI to 
ensure they are transformable.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61102 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 21:24:51 +00:00
Chris Lattner
542dc1a0de fix a crash found by inspection.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61101 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 21:04:51 +00:00
Eli Friedman
080efb8cea Add a helper to remove a branch and DCE the condition, and use it
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
2008-12-16 20:54:32 +00:00
Chris Lattner
f478951b0e fix PR3217: fully cached queries need to be verified against the
visited set before they are used.  If used, their blocks need to be
added to the visited set so that subsequent queries don't use conflicting
pointer values in the cache result blocks.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61080 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-16 07:10:09 +00:00
Chris Lattner
657084a8ea add testcase for r61051
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61052 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 21:46:23 +00:00
Chris Lattner
ca17422158 add a basic test for heap-sra
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61041 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 19:42:05 +00:00
Chris Lattner
8f416f3afd Add a testcase for GCC PR 23455, which lpre handles now. Add some
comments about why we're not getting other cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61032 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 07:49:24 +00:00
Chris Lattner
ef423ebdd1 gvn now hoists this load out of the hot non-call path.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61028 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 06:34:48 +00:00
Chris Lattner
4807e07fff Adjust testcase to make it more stable across visitation order changes,
unbreaking it after r61024.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61025 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 04:42:00 +00:00
Chris Lattner
f33131685b make GVN try to rename inputs to the resultant replaced values, which
cleans up the generated code a bit.  This should have the added benefit of
not randomly renaming functions/globals like my previous patch did. :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61023 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 03:46:38 +00:00
Chris Lattner
9e59c64c14 Implement initial support for PHI translation in memdep. This means that
memdep keeps track of how PHIs affect the pointer in dep queries, which 
allows it to eliminate the load in cases like rle-phi-translate.ll, which
basically end up being:

BB1:
   X = load P
   br BB3
BB2:
   Y = load Q
   br BB3
BB3:
   R = phi [P] [Q]
   load R

turning "load R" into a phi of X/Y.  In addition to additional exposed
opportunities, this makes memdep safe in many cases that it wasn't before
(which is required for load PRE) and also makes it substantially more 
efficient.  For example, consider:


bb1:  // has many predecessors.
   P = some_operator()
   load P

In this example, previously memdep would scan all the predecessors of BB1
to see if they had something that would mustalias P.  In some cases (e.g.
test/Transforms/GVN/rle-must-alias.ll) it would actually find them and end
up eliminating something.  In many other cases though, it would scan and not
find anything useful.  MemDep now stops at a block if the pointer is defined
in that block and cannot be phi translated to predecessors.  This causes it
to miss the (rare) cases like rle-must-alias.ll, but makes it faster by not
scanning tons of stuff that is unlikely to be useful.  For example, this
speeds up GVN as a whole from 3.928s to 2.448s (60%)!.  IMO, scalar GVN 
should be enhanced to simplify the rle-must-alias pointer base anyway, which
would allow the loads to be eliminated.

In the future, this should be enhanced to phi translate through geps and 
bitcasts as well (as indicated by FIXMEs) making memdep even more powerful.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61022 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-15 03:35:32 +00:00
Chris Lattner
5c6d91c1d1 another random testcase that shouldn't crash gvn and is
good for coverage with future changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@61011 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-14 21:20:46 +00:00
Chris Lattner
3f101bb1e7 RLE isn't smart enough to eliminate this safely yet.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60994 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-13 21:04:20 +00:00
Chris Lattner
4f118f0a20 rename some tests to be more uniform in naming convention.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60988 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-13 18:47:40 +00:00
Chris Lattner
c2f33f24af gvn should never crash on this.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60987 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-13 18:39:44 +00:00
Bill Wendling
8295e49e76 Temporarily revert r60973. It's inexplicably causing a failure when self-hosting LLVM:
llvm[2]: Linking Release executable opt (without symbols)
...
Undefined symbols:
  "llvm::APFloat::IEEEsingle", referenced from:
      __ZN4llvm7APFloat10IEEEsingleE$non_lazy_ptr in libLLVMCore.a(Constants.o)
      __ZN4llvm7APFloat10IEEEsingleE$non_lazy_ptr in libLLVMCore.a(AsmWriter.o)
      __ZN4llvm7APFloat10IEEEsingleE$non_lazy_ptr in libLLVMCore.a(ConstantFold.o)
  "llvm::APFloat::IEEEdouble", referenced from:
      __ZN4llvm7APFloat10IEEEdoubleE$non_lazy_ptr in libLLVMCore.a(Constants.o)
      __ZN4llvm7APFloat10IEEEdoubleE$non_lazy_ptr in libLLVMCore.a(AsmWriter.o)
      __ZN4llvm7APFloat10IEEEdoubleE$non_lazy_ptr in libLLVMCore.a(ConstantFold.o)
ld: symbol(s) not found

This is in release mode. To replicate, compile llvm and llvm-gcc in optimized
mode. Then build llvm, in optimized mode, with the newly created compiler.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60977 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-13 09:28:44 +00:00
Chris Lattner
879922932f make RLE preserve the name of the load that it replaces. This is just
a pretification of the IR.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60973 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-13 07:22:47 +00:00
Chris Lattner
5a45bf1b48 loosen up an assertion that isn't valid when called from
invalidateCachedPointerInfo.  Thanks to Bill for sending me
a testcase.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60805 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-09 22:45:32 +00:00
Chris Lattner
20d6f0982a Teach BasicAA::getModRefInfo(CallSite, CallSite) some
tricks based on readnone/readonly functions.

Teach memdep to look past readonly calls when analyzing
deps for a readonly call.  This allows elimination of a
few more calls from 403.gcc:

before:
     63 gvn    - Number of instructions PRE'd
 153986 gvn    - Number of instructions deleted
  50069 gvn    - Number of loads deleted

after:
     63 gvn    - Number of instructions PRE'd
 153991 gvn    - Number of instructions deleted
  50069 gvn    - Number of loads deleted

5 calls isn't much, but this adds plumbing for the next change.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60794 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-09 21:19:42 +00:00
Devang Patel
51d8b669f1 Actually test something. Use PR3170 test case.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60727 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-08 23:44:46 +00:00
Devang Patel
6d9896f153 Undo previous patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60701 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-08 17:02:37 +00:00
Chris Lattner
a16ead8b10 fix a bug I introduced in simplifycfg handling single entry phi
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
2008-12-07 07:22:45 +00:00
Chris Lattner
5e600e67b1 Reimplement the inner loop of DSE. It now uniformly uses getDependence(),
doesn't do its own local caching, and is slightly more aggressive about
free/store dse (see testcase).  This eliminates the last external client 
of MemDep::getDependenceFrom().


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60619 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-06 00:53:22 +00:00
Chris Lattner
7f7c736682 Fix test/Transforms/GVN/pre-load.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60594 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-05 17:04:12 +00:00
Devang Patel
3831005eb1 Rewrite code that 1) filters loops and 2) calculates new loop bounds.
This fixes many bugs. I will add more test cases in a separate check-in.

Some day, the code that manipulates CFG and updates dom. info could use refactoring help.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60554 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-04 21:38:42 +00:00
Chris Lattner
2a5dc33c57 testcase for br undef folding.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60471 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03 07:48:27 +00:00
Chris Lattner
421fa9e32e Teach jump threading some more simple tricks:
1) have it fold "br undef", which does occur with
   surprising frequency as jump threading iterates.
2) teach j-t to delete dead blocks.  This removes the successor
   edges, reducing the in-edges of other blocks, allowing 
   recursive simplification.
3) Fold things like:
     br COND, BBX, BBY
  BBX:
     br COND, BBZ, BBW

   which also happens because jump threading iterates.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60470 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03 07:48:08 +00:00
Chris Lattner
1ea7771e09 don't spew tons of stuff to the output. This testcase is *not* for
loop deletion (it is for a ton of passes), which is very bad.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60465 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-03 06:41:50 +00:00
Chris Lattner
c89c6a964c Implement PRE of loads in the GVN pass with a pretty cheap and
straight-forward implementation.  This does not require any extra
alias analysis queries beyond what we already do for non-local loads.

Some programs really really like load PRE.  For example, SPASS triggers
this ~1000 times, ~300 times in 255.vortex, and ~1500 times on 403.gcc.

The biggest limitation to the implementation is that it does not split
critical edges.  This is a huge killer on many programs and should be
addressed after the initial patch is enabled by default.

The implementation of this should incidentally speed up rejection of 
non-local loads because it avoids creating the repl densemap in cases 
when it won't be used for fully redundant loads.

This is currently disabled by default.
Before I turn this on, I need to fix a couple of miscompilations in
the testsuite, look at compile time performance numbers, and look at
perf impact.  This is pretty close to ready though.




git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60408 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-02 08:16:11 +00:00
Owen Anderson
e209d9a3e6 Add a test for my previous PRE fix.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60394 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-02 04:25:42 +00:00
Bill Wendling
03aae5f7e1 Use m_Specific() instead of double matching.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60341 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 08:09:47 +00:00
Chris Lattner
d8aafcb200 simplify these patterns using m_Specific. No need to grep for
xor in testcase (or is a substring).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60328 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 05:16:26 +00:00
Chris Lattner
05f18920e1 Teach inst combine to merge GEPs through PHIs. This is really
important because it is sinking the loads using the GEPs, but
not the GEPs themselves.  This triggers 647 times on 403.gcc
and makes the .s file much much nicer.  For example before:

        je      LBB1_87 ## bb78
LBB1_62:        ## bb77
        leal    84(%esi), %eax
LBB1_63:        ## bb79
        movl    (%eax), %eax
...
LBB1_87:        ## bb78
        movl    $0, 4(%esp)
        movl    %esi, (%esp)
        call    L_make_decl_rtl$stub
        jmp     LBB1_62 ## bb77


after:

        jne     LBB1_63 ## bb79
LBB1_62:        ## bb78
        movl    $0, 4(%esp)
        movl    %esi, (%esp)
        call    L_make_decl_rtl$stub
LBB1_63:        ## bb79
        movl    84(%esi), %eax

The input code was (and the GEPs are merged and
the PHI is now eliminated by instcombine):

        br i1 %tmp233, label %bb78, label %bb77
bb77:           
        %tmp234 = getelementptr %struct.tree_node* %t_addr.3, i32 0, i32 0, i32 22              
        br label %bb79
bb78:           
        call void @make_decl_rtl(%struct.tree_node* %t_addr.3, i8* null) nounwind
        %tmp235 = getelementptr %struct.tree_node* %t_addr.3, i32 0, i32 0, i32 22              
        br label %bb79
bb79:           
        %iftmp.12.0.in = phi %struct.rtx_def** [ %tmp235, %bb78 ], [ %tmp234, %bb77 ]           
        %iftmp.12.0 = load %struct.rtx_def** %iftmp.12.0.in             



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60322 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 02:34:36 +00:00
Chris Lattner
67afda6c1e testcase for my previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60315 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 01:42:03 +00:00
Bill Wendling
b3833d1eb9 Implement ((A|B)&1)|(B&-2) -> (A&1) | B transformation. This also takes care of
permutations of this pattern.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60312 91177308-0d34-0410-b5e6-96231b3b80d8
2008-12-01 01:07:11 +00:00
Bill Wendling
b01865c210 Add instruction combining for ((A&~B)|(~A&B)) -> A^B and all permutations.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@60291 91177308-0d34-0410-b5e6-96231b3b80d8
2008-11-30 13:52:49 +00:00