Commit Graph

1341 Commits

Author SHA1 Message Date
Chris Lattner
59fdaeeae8 Change the canonical induction variable that we insert.
Instead of producing code like this:

Loop:
  X = phi 0, X2
  ...

  X2 = X + 1
  if (X != N-1) goto Loop

We now generate code that looks like this:

Loop:
  X = phi 0, X2
  ...

  X2 = X + 1
  if (X2 != N) goto Loop

This has two big advantages:
  1. The trip count of the loop is now explicit in the code, allowing
     the direct implementation of Loop::getTripCount()
  2. This reduces register pressure in the loop, and allows X and X2 to be
     put into the same register.

As a consequence of the second point, the code we generate for loops went
from:

.LBB2:  # no_exit.1
	...
        mov %EDI, %ESI
        inc %EDI
        cmp %ESI, 2
        mov %ESI, %EDI
        jne .LBB2 # PC rel: no_exit.1

To:

.LBB2:  # no_exit.1
	...
        inc %ESI
        cmp %ESI, 3
        jne .LBB2 # PC rel: no_exit.1

... which has two fewer moves, and uses one less register.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12961 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-15 15:21:43 +00:00
Chris Lattner
d9955aaa61 ADd a trivial instcombine: load null -> null
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12940 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-14 03:28:36 +00:00
Chris Lattner
58b7b08ad7 Add SCCP support for constant folding calls, implementing:
test/Regression/Transforms/SCCP/calltest.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12921 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 19:43:54 +00:00
Chris Lattner
25b8390bf2 Add a simple call constant propagation interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12919 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 19:28:52 +00:00
Chris Lattner
4647b7cd69 Constant propagation should remove the dead instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12917 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 19:28:20 +00:00
Chris Lattner
4b66242c54 Fix LoopSimplify/2004-04-13-LoopSimplifyUpdateDomFrontier.ll
LoopSimplify was not updating dominator frontiers correctly in some cases.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12890 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 16:23:25 +00:00
Chris Lattner
1f62f82b05 Refactor code a bit to make it simpler and eliminate the goto
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12888 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 15:21:18 +00:00
Chris Lattner
529b28da45 This patch addresses PR35: Loop simplify should reconstruct nested loops.
This is fairly straight-forward, but was a real nightmare to get just
perfect.  aarg.  :)


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12884 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-13 05:05:33 +00:00
Chris Lattner
ce1a3a292d Actually update the call graph as the inliner changes it. This allows us to
execute other CallGraphSCCPasses after the inliner without crashing.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12861 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 05:37:29 +00:00
Chris Lattner
1708d12916 Add support for removing invoke instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12858 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 05:15:13 +00:00
Chris Lattner
85eb157d96 Stop printing Function*
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12857 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 04:06:56 +00:00
Chris Lattner
d08ddd3300 Simplify code a bit, and be sure to mark the external node as potentially throwing
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12856 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-12 04:06:38 +00:00
Chris Lattner
fbede52af4 Fix a bug in my select transformation
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12826 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-11 01:39:19 +00:00
Chris Lattner
adb7c0de39 Update the value numbering interface.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12824 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 22:33:34 +00:00
Chris Lattner
d76956d444 Implement InstCombine/select.ll:test13*
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12821 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 22:21:27 +00:00
Chris Lattner
66331a4e33 Implement InstCombine/add.ll:test20
Canonicalize add of sign bit constant into a xor


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12819 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 22:01:55 +00:00
Chris Lattner
38e66bd9d1 Rewrite the GCSE pass to be *substantially* simpler, a bit more efficient,
and a bit more powerful


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12817 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 21:11:11 +00:00
Chris Lattner
326c0f3013 Fix spurious warning in release mode
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12816 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 19:15:56 +00:00
Chris Lattner
a5f4103931 Simplify code a bit, and fix a bug that was breaking perlbmk
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12814 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 18:06:21 +00:00
Chris Lattner
562cb66b84 Fix a bug in my checkin last night that was breaking programs using invoke.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12813 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 16:53:29 +00:00
Chris Lattner
27c694bacb Fix previous patch
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12811 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 07:27:48 +00:00
Chris Lattner
17177601fb Correctly update counters
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12810 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 07:02:02 +00:00
Chris Lattner
ede6ac60a5 Simplify code a bit, and use alias analysis to allow us to delete unused
call and invoke instructions that are known to not write to memory.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12807 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-10 06:53:09 +00:00
Chris Lattner
e576b91948 Implement select.ll:test12*
This transforms code like this:

   %C = or %A, %B
   %D = select %cond, %C, %A
into:
   %C = select %cond, %B, 0
   %D = or %A, %C

Since B is often a constant, the select can often be eliminated.  In any case,
this reduces the usage count of A, allowing subsequent optimizations to happen.

This xform applies when the operator is any of:
  add, sub, mul, or, xor, and, shl, shr


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12800 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-09 23:46:01 +00:00
Chris Lattner
570751c2a7 Fold code like:
if (C)
    V1 |= V2;

into:
  Vx = V1 | V2;
  V1 = select C, V1, Vx

when the expression can be evaluated unconditionally and is *cheap* to
execute.  This limited form of if conversion is quite handy in lots of cases.
For example, it turns this testcase into straight-line code:

int in0 ; int in1 ; int in2 ; int in3 ;
int in4 ; int in5 ; int in6 ; int in7 ;
int in8 ; int in9 ; int in10; int in11;
int in12; int in13; int in14; int in15;
long output;

void mux(void) {
  output =
      (in0   ?  0x00000001 : 0) | (in1   ?  0x00000002 : 0) |
      (in2   ?  0x00000004 : 0) | (in3   ?  0x00000008 : 0) |
      (in4   ?  0x00000010 : 0) | (in5   ?  0x00000020 : 0) |
      (in6   ?  0x00000040 : 0) | (in7   ?  0x00000080 : 0) |
      (in8   ?  0x00000100 : 0) | (in9   ?  0x00000200 : 0) |
      (in10  ?  0x00000400 : 0) | (in11  ?  0x00000800 : 0) |
      (in12  ?  0x00001000 : 0) | (in13  ?  0x00002000 : 0) |
      (in14  ?  0x00004000 : 0) | (in15  ?  0x00008000 : 0) ;
}


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12798 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-09 22:50:22 +00:00
Chris Lattner
2eefe518de Fold binary operators with a constant operand into select instructions
that have a constant operand.  This implements
add.ll:test19, shift.ll:test15*, and others that are not tested


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12794 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-09 19:05:30 +00:00
Chris Lattner
82e14fe168 Implement select.ll:test11
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12793 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-09 18:19:44 +00:00
Chris Lattner
f499eaca36 Implement InstCombine/cast-propagate.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12784 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-08 20:39:49 +00:00
Chris Lattner
8ba725b456 Implement ScalarRepl/select_promote.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12779 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-08 19:59:34 +00:00
Chris Lattner
775cbdd51a Remove the "really gross hacks" that are there to deal with recursive functions.
Now we collect all of the call sites we are interested in inlining, then inline
them.  This entirely avoids issues with trying to inline a call site we got by
inlining another call site.  This also eliminates iterator invalidation issues.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12770 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-08 06:34:31 +00:00
Chris Lattner
0c199a7628 Implement InstCombine/select.ll:test[7-10]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12769 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-08 04:43:23 +00:00
Chris Lattner
cb69a4ed64 Implement test/Regression/Transforms/InstCombine/getelementptr_index.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12762 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-07 18:38:20 +00:00
Chris Lattner
548f47efb0 Fix a bug in yesterdays checkins which broke siod. siod is a great testcase! :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12659 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-05 16:02:41 +00:00
Chris Lattner
15a76c0b35 Fix InstCombine/2004-04-04-InstCombineReplaceAllUsesWith.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12658 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-05 02:10:19 +00:00
Chris Lattner
28977af72a Support getelementptr instructions which use uint's to index into structure
types and can have arbitrary 32- and 64-bit integer types indexing into
sequential types.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12653 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-05 01:30:19 +00:00
Chris Lattner
40bf8b48cd Rewrite the indvars pass to use the ScalarEvolution analysis.
This also implements some new features for the indvars pass, including
linear function test replacement, exit value substitution, and it works with
a much more general class of induction variables and loops.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12620 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-02 20:24:31 +00:00
Chris Lattner
7aa773bc07 Fix the obvious bug in my previous checkin
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12618 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-02 18:15:10 +00:00
Chris Lattner
147af6b75f Implement Transforms/SimplifyCFG/return-merge.ll
This actually causes us to turn code like:

  return C ? A : B;

into a select instruction.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12617 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-02 18:13:43 +00:00
Chris Lattner
c68bace452 Fix PR310 and TailDup/2004-04-01-DemoteRegToStack.llx
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12597 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-01 20:28:45 +00:00
Chris Lattner
4edf6c043e Remove some assertions that are now bogus with the last patch I put in
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12595 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-01 19:21:46 +00:00
Chris Lattner
4f303bd4a5 Fix PR306: Loop simplify incorrectly updates dominator information
Testcase: LoopSimplify/2004-04-01-IncorrectDomUpdate.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12592 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-01 19:06:07 +00:00
Chris Lattner
0e28eca4bc Add warning
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12573 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-31 22:00:30 +00:00
Chris Lattner
1438102576 Fix linking of constant expr casts due to type resolution changes. With
this and the other patches 253.perlbmk links again.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12565 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-31 02:58:28 +00:00
Brian Gaeke
87fa610ee0 Start cleaning up this pass so that I can debug it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12548 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-30 19:53:46 +00:00
Chris Lattner
552112f2f8 Now that all the code generators support the select instruction, and the instcombine
pass can eliminate many nasty cases of them, start generating them in the optimizers


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12545 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-30 19:44:05 +00:00
Chris Lattner
c32b30a429 Implement select.ll:test[3-6]
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12544 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-30 19:37:13 +00:00
Chris Lattner
18bdbc3dda Add a simple select instruction lowering pass
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12540 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-30 18:41:10 +00:00
Chris Lattner
4df1b8aa26 X % -1 == X % 1 == 0
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12520 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-26 16:11:24 +00:00
Chris Lattner
ebd985cb87 Two changes:
#1 is to unconditionally strip constantpointerrefs out of
instruction operands where they are absolutely pointless and inhibit
optimization.  GRRR!

#2 is to implement InstCombine/getelementptr_const.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12519 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-25 22:59:29 +00:00
Chris Lattner
7c881dffc9 Teach the optimizer to delete zero sized alloca's (but not mallocs!)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12507 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-19 06:08:10 +00:00