Commit Graph

1638 Commits

Author SHA1 Message Date
Chris Lattner
061718cba8 Implement InstCombine/getelementptr.ll:test9, which is the source of many
ugly and giant constnat exprs in some programs.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17066 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 19:44:59 +00:00
Chris Lattner
ec7c1ab1da Add support for unreachable
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17056 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 18:21:33 +00:00
Chris Lattner
e87597fb75 Optimize instructions involving undef values. For example X+undef == undef.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17047 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 18:11:37 +00:00
Chris Lattner
82731c793a Add support for UndefValue
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17046 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 18:10:31 +00:00
Chris Lattner
b20724dff4 When promoting mem2reg, make uninitialized values become undef isntead of 0.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17045 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 18:10:06 +00:00
Chris Lattner
5d356a7c82 Handle undef values as undefined on the constant lattice
ignore unreachable instructions


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17044 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 18:09:41 +00:00
Chris Lattner
b2f59a2af7 Add note
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17043 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 18:09:25 +00:00
Chris Lattner
7a7ed0274d Add support for the undef value. Implement a new optimization based on globals
that are initialized with undef.  When promoting malloc to a global, start out
initialized to undef


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17042 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-16 18:09:00 +00:00
Chris Lattner
b23cd2f688 Fix a bug John tracked down in libstdc++ where we were incorrectly deleting
weak functions.  Thanks for finding this John!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16997 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-14 19:53:50 +00:00
Chris Lattner
9c07866ef8 When converting phi nodes into select instructions, we shouldn't promote PHI
nodes unless we KNOW that we are able to promote all of them.

This fixes: test/Regression/Transforms/SimplifyCFG/PhiNoEliminate.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16973 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-14 05:13:36 +00:00
Reid Spencer
d96cb6eaa0 Update to reflect changes in Makefile rules.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16950 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-13 11:46:52 +00:00
Chris Lattner
35b9e48cfd Transform memmove -> memcpy when the source is obviously constant memory.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16932 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-12 04:52:52 +00:00
Chris Lattner
989cbd58fb Fix a REALLY obscure bug in my previous checkin, which was splicing the END
marker from one ilist into the middle of another basic block!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16925 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-12 01:02:29 +00:00
Chris Lattner
a4b9c7841f Handle a common case more carefully. In particular, instead of transforming
pointer recurrences into expressions from this:

  %P_addr.0.i.0 = phi sbyte* [ getelementptr ([8 x sbyte]* %.str_1, int 0, int 0), %entry ], [ %inc.0.i, %no_exit.i ]
  %inc.0.i = getelementptr sbyte* %P_addr.0.i.0, int 1            ; <sbyte*> [#uses=2]

into this:

  %inc.0.i = getelementptr sbyte* getelementptr ([8 x sbyte]* %.str_1, int 0, int 0), int %inc.0.i.rec

Actually create something nice, like this:

  %inc.0.i = getelementptr [8 x sbyte]* %.str_1, int 0, int %inc.0.i.rec


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16924 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-11 23:06:50 +00:00
Chris Lattner
6a9fdfaec8 Reenable the transform, turning X/-10 < 1 into X > -10
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16918 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-11 19:40:04 +00:00
Chris Lattner
30ba5690cf This patch implements two things (sorry).
First, it allows SRA of globals that have embedded arrays, implementing
GlobalOpt/globalsra-partial.llx.  This comes up infrequently, but does allow,
for example, deleting several stores to dead parts of globals in dhrystone.

Second, this implements GlobalOpt/malloc-promote-*.llx, which is the
following nifty transformation:

Basically if a global pointer is initialized with malloc, and we can tell
that the program won't notice, we transform this:

struct foo *FooPtr;
...
  FooPtr = malloc(sizeof(struct foo));
...
  FooPtr->A   FooPtr->B

Into:

struct foo FooPtrBody;
...
   FooPtrBody.A  FooPtrBody.B

This comes up occasionally, for example, the 'disp' global in 183.equake (where
the xform speeds the CBE version of the program up from 56.16s to 52.40s (7%)
on apoc), and the 'desired_accept', 'fixLRBT', 'macroArray', & 'key_queue'
globals in 300.twolf (speeding it up from 22.29s to 21.55s (3.4%)).

The nice thing about this xform is that it exposes the resulting global to
global variable optimization and makes alias analysis easier in addition to
eliminating a few loads.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16916 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-11 05:54:41 +00:00
Chris Lattner
708148e41f Just because we cannot completely eliminate all uses of a global, we can
still optimize away all of the indirect calls and loads, etc from it.
This turns code like this:

  if (G != 0)
    G();

into
   if (G != 0)
     ActualCallee();

This triggers a couple of times in gcc and libstdc++.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16901 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-10 23:14:11 +00:00
Reid Spencer
81f76b324e Initial version of automake Makefile.am file.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16893 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-10 22:20:40 +00:00
Chris Lattner
8be8012ba4 Fix 2004-10-10-CastStoreOnce.llx, by adjusting types back if we strip off a cast
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16878 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-10 17:07:12 +00:00
Chris Lattner
c4d81b0388 Implement GlobalOpt/deadglobal-2.llx, deletion of globals that are only
stored to, but are stored at variable indexes.  This occurs at least in
176.gcc, but probably others, and we should handle it for completeness.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16876 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-10 16:47:33 +00:00
Chris Lattner
031955d462 Avoid calling use_size() which could (in theory) be expensive if the global
has a large number of users.  Instead, just keep track of whether we're
making changes as we do so.

This patch has no functionlity changes.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16874 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-10 16:43:46 +00:00
Chris Lattner
9b34a61019 Eliminate global pointers that are only stored a single value and null if
we know that all uses of the global will trap if the pointer contained is
null.  In this case, we forward substitute the stored value to any uses.

This has the effect of devirtualizing trivial globals in trivial cases.  For
example, 164.gzip contains this:

gzip.h:extern   int (*read_buf) OF((char *buf, unsigned size));
bits.c: read_buf  = file_read;
deflate.c:    lookahead = read_buf((char*)window,
deflate.c:        n = read_buf((char*)window+strstart+lookahead, more);

Since read_buf has to point to file_read at every use, we just replace
the calls through read_buf with a direct call to file_read.

This occurs in several benchmarks, including 176.gcc and 164.gzip.  Direct
calls are good and stuff.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16871 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-09 21:48:45 +00:00
Chris Lattner
dd27827733 Use DEBUG instead of DebugFlag directly, as DebugFlag does not respect
-debug-only!


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16868 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-09 19:30:36 +00:00
Chris Lattner
930f475604 Fix infinite loop due to iteration
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16864 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-09 03:32:52 +00:00
Chris Lattner
a052f8297a Implement sub.ll:test17, -X/C -> X/-C
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16863 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-09 02:50:40 +00:00
Chris Lattner
8f57e9c083 If we found a dead global, we should at least delete it...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16858 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-08 22:05:31 +00:00
Chris Lattner
a4be1dc0a1 * Pull out the meat of runOnModule into another function for clarity.
* Do not lead dangling dead constants prevent optimization
* Iterate global optimization while we're making progress.

These changes allow us to be more aggressive, handling cases like
GlobalOpt/iterate.llx without a problem (turning it into 'ret int 0').


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16857 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-08 20:59:28 +00:00
Chris Lattner
e40e2d1a71 We might as well delete the known-dead global sooner rather than later since
we know it is dead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16855 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-08 20:25:55 +00:00
Chris Lattner
340a05fb3a Temporarily disable a buggy transformation until it can be fixed. This fixes
254.gap.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16853 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-08 19:15:44 +00:00
Chris Lattner
670c889ac9 Implement SRA for global variables. This allows the other global variable
optimizations to trigger much more often.  This allows the elimination of
several dozen more global variables in Programs/External.  Note that we only
do this for non-constant globals: constant globals will already be optimized
out if the accesses to them permit it.

This implements Transforms/GlobalOpt/globalsra.llx


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16842 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-08 17:32:09 +00:00
Chris Lattner
b99d6b1cac Instcombine (X & FF00) + xx00 -> (X+xx00) & FF00, implementing and.ll:test27
This comes up when doing adds to bitfield elements.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16836 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-08 05:07:56 +00:00
Chris Lattner
1f7e160f77 Little patch to turn (shl (add X, 123), 4) -> (add (shl X, 4), 123 << 4)
This triggers in cases of bitfield additions, opening opportunities for
future improvements.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16834 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-08 03:46:20 +00:00
Chris Lattner
cf4d2a5699 Improve comments, no functionality changes
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16814 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-07 21:30:30 +00:00
Chris Lattner
3602549c3d Fix a bug in the safety analysis routine
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16804 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-07 06:01:25 +00:00
Chris Lattner
bc53e5e628 Comment cleanups
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16803 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-07 06:00:24 +00:00
Chris Lattner
7a90b68e5c * Rename pass to globalopt, since we do more than just constify
* Instead of handling dead functions specially, just nuke them.
* Be more aggressive about cleaning up after constification, in
  particular, handle getelementptr instructions and constantexprs.
* Be a little bit more structured about how we process globals.

*** Delete globals that are only stored to, and never read.  These are
    clearly not useful, so they should go.  This implements deadglobal.llx

This last one triggers quite a few times.  In particular, 2208 in the
external tests, 1865 of which are in 252.eon.  This shrinks eon from
1995094 to 1732341 bytes of bytecode.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16802 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-07 04:16:33 +00:00
Chris Lattner
e47ba74b07 Implement GlobalConstifier/trivialstore.llx, and also do some
simplifications of the resultant program to avoid making later passes
do it all.

This allows us to constify globals that just have the same constant that
they are initialized stored into them.

Suprisingly this comes up ALL of the freaking time, dozens of times in
SPEC, 30 times in vortex alone.

For example, on 256.bzip2, it allows us to constify these two globals:

%smallMode = internal global ubyte 0             ; <ubyte*> [#uses=8]
%verbosity = internal global int 0               ; <int*> [#uses=49]

Which (with later optimizations) results in the bytecode file shrinking
from 82286 to 69686 bytes!  Lets hear it for IPO :)

For the record, it's nuking lots of "if (verbosity > 2) { do lots of stuff }"
code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16793 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-06 20:57:02 +00:00
Chris Lattner
91ccc15b45 Instcombine: -(X sdiv C) -> (X sdiv -C), tested by sub.ll:test16
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16769 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-06 15:08:25 +00:00
Chris Lattner
c3e903fe65 Reduce code growth implied by the tail duplication pass by not duplicating
an instruction if it can be hoisted to a common dominator of the block.
This implements: test/Regression/Transforms/TailDup/MergeTest.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16758 91177308-0d34-0410-b5e6-96231b3b80d8
2004-10-06 03:27:37 +00:00
Brian Gaeke
f098ced848 Add accessor function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16622 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-30 20:14:29 +00:00
Brian Gaeke
b3b1e33632 Correct type of accessor functions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16621 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-30 20:14:18 +00:00
Brian Gaeke
ccb87cdf07 Namespacify. Add accessor function.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16620 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-30 20:14:07 +00:00
Chris Lattner
23367a779c Disable the 'WARNING: Found global types that are not compatible' warning
that always prints when linking programs to libstdc++ :(


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16603 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-30 00:12:29 +00:00
Chris Lattner
a71989f11b Hrm, debugging printouts do not need to be in here
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16598 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-29 21:21:14 +00:00
Chris Lattner
a96879a26d * Pull range optimization code out into new InsertRangeTest function.
* SubOne/AddOne functions always return ConstantInt, declare them as such
* Pull code for handling setcc X, cst, where cst is at the end of the range,
  or cc is LE or GE up earlier in visitSetCondInst.  This reduces #iterations
  in some cases.
* Fold: (div X, C1) op C2 -> range check, implementing div.ll:test6 - test9.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16588 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-29 17:40:11 +00:00
Chris Lattner
0ed7f42c1b Do not insert trivially dead select instructions, which allows us to
potentially fold more in one pass.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16583 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-29 05:43:32 +00:00
Chris Lattner
4e998b2fea Fold binary expressions and casts into PHI nodes that have all constant inputs.
This takes something like this:

%A = phi int [ 3, %cond_false.0 ], [ 2, %endif.0.i ], [ 2, %endif.1.i ]
%B = div int %tmp.243, 4

and turns it into:

%A = phi int [ 3/4, %cond_false.0 ], [ 2/4, %endif.0.i ], [ 2/4, %endif.1.i ]

which is later simplified (in this case) into %A = 0.

This triggers thousands of times in spec, for example, 269 times in 176.gcc.

This is tested by InstCombine/add.ll:test23 and set.ll:test18.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16582 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-29 05:07:12 +00:00
Chris Lattner
dd763f401e Hrm, really, all tests passed without this, but it is scary to think how...
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16568 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-29 03:16:24 +00:00
Chris Lattner
f6d1d7d2ba Remove debugging printout
Instcombine (setcc (truncate X), C1).

This occurs THOUSANDS of times in many benchmarks.  Particularlly common
seem to be things like (seteq (cast bool X to int), int 0)

This turns it into (seteq bool %X, false), which then becomes (not %X).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16567 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-29 03:09:18 +00:00
Chris Lattner
b4f40d2059 Fold (X setcc C1) | (X setcc C2)
This implements or.ll:test1[89]


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@16561 91177308-0d34-0410-b5e6-96231b3b80d8
2004-09-28 22:33:08 +00:00