Commit Graph

533 Commits

Author SHA1 Message Date
Chris Lattner
006118fe8c Fix some of the strange CBE-only failures that happened last night.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12980 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-16 06:03:17 +00:00
Chris Lattner
d244057a48 Fix a bug in the previous checkin: if the exit block is not the same as
the back-edge block, we must check the preincremented value.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12968 91177308-0d34-0410-b5e6-96231b3b80d8
2004-04-15 20:26:22 +00:00
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
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
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
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
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
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
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
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
Chris Lattner
e911979650 Be more accurate
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12464 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-17 01:59:27 +00:00
Chris Lattner
50eafbc828 Fix bug in previous checkin
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12458 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-16 23:36:49 +00:00
Chris Lattner
24ad00db5a Okay, so there is no reasonable way for tail duplication to update SSA form,
as it is making effectively arbitrary modifications to the CFG and we don't
have a domset/domfrontier implementations that can handle the dynamic updates.
Instead of having a bunch of code that doesn't actually work in practice,
just demote any potentially tricky values to the stack (causing the problem
to go away entirely).  Later invocations of mem2reg will rebuild SSA for us.

This fixes all of the major performance regressions with tail duplication
from LLVM 1.1.  For example, this loop:

---
int popcount(int x) {
  int result = 0;
  while (x != 0) {
    result = result + (x & 0x1);
    x = x >> 1;
  }
  return result;
}
---
Used to be compiled into:

int %popcount(int %X) {
entry:
	br label %loopentry

loopentry:		; preds = %entry, %no_exit
	%x.0 = phi int [ %X, %entry ], [ %tmp.9, %no_exit ]		; <int> [#uses=3]
	%result.1.0 = phi int [ 0, %entry ], [ %tmp.6, %no_exit ]		; <int> [#uses=2]
	%tmp.1 = seteq int %x.0, 0		; <bool> [#uses=1]
	br bool %tmp.1, label %loopexit, label %no_exit

no_exit:		; preds = %loopentry
	%tmp.4 = and int %x.0, 1		; <int> [#uses=1]
	%tmp.6 = add int %tmp.4, %result.1.0		; <int> [#uses=1]
	%tmp.9 = shr int %x.0, ubyte 1		; <int> [#uses=1]
	br label %loopentry

loopexit:		; preds = %loopentry
	ret int %result.1.0
}

And is now compiled into:

int %popcount(int %X) {
entry:
        br label %no_exit

no_exit:                ; preds = %entry, %no_exit
        %x.0.0 = phi int [ %X, %entry ], [ %tmp.9, %no_exit ]          ; <int> [#uses=2]
        %result.1.0.0 = phi int [ 0, %entry ], [ %tmp.6, %no_exit ]             ; <int> [#uses=1]
        %tmp.4 = and int %x.0.0, 1              ; <int> [#uses=1]
        %tmp.6 = add int %tmp.4, %result.1.0.0          ; <int> [#uses=2]
        %tmp.9 = shr int %x.0.0, ubyte 1                ; <int> [#uses=2]
        %tmp.1 = seteq int %tmp.9, 0            ; <bool> [#uses=1]
        br bool %tmp.1, label %loopexit, label %no_exit

loopexit:               ; preds = %no_exit
        ret int %tmp.6
}


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12457 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-16 23:29:09 +00:00
Chris Lattner
a2f652d420 Do not try to optimize PHI nodes with incredibly high degree. This reduces SCCP
time from 615s to 1.49s on a large testcase that has a gigantic switch statement
that all of the blocks in the function go to (an intepreter).


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12442 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-16 19:49:59 +00:00
Chris Lattner
4bebf08d15 Do not copy gigantic switch instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12441 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-16 19:45:22 +00:00
Chris Lattner
46234fd97f Add counters for the number of calls elimianted
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12420 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-15 05:46:59 +00:00
Chris Lattner
118dd0ce3d Implement LICM of calls in simple cases. This is sufficient to move around
sin/cos/strlen calls and stuff.  This implements:
  LICM/call_sink_pure_function.ll
  LICM/call_sink_const_function.ll


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12415 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-15 04:11:30 +00:00
Chris Lattner
0cea42a560 Add some debugging output
Fix InstCombine/2004-03-13-InstCombineInfLoop.ll which caused an infinite
loop compiling (I think) povray.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12365 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-13 23:54:27 +00:00
Chris Lattner
bfe492b5c2 Implement sub.ll:test14
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12355 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-13 00:11:49 +00:00
Chris Lattner
9c2906744a Implement InstCombine/sub.ll:test12 & test13
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12353 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-12 23:53:13 +00:00
Chris Lattner
6e32372fcd Add sccp support for select instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12318 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-12 05:52:44 +00:00
Chris Lattner
3d69f46d64 Add trivial optimizations for select instructions
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12317 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-12 05:52:32 +00:00
Chris Lattner
c76d80342e Since 'load null' is undefined, we can make it do whatever we want. Returning
a zero value is the most likely way to cause further simplification, so we do it.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12197 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-07 22:16:24 +00:00
Chris Lattner
99cca7d3aa Disable tail duplication in a case that breaks on Olden/tsp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12021 91177308-0d34-0410-b5e6-96231b3b80d8
2004-03-01 01:12:13 +00:00
Chris Lattner
4279f3c984 Fix PR255: [tailduplication] Single basic block loops are very rare
Note that this is a band-aid put over a band-aid.  This just undisables
tail duplication in on very specific case that it seems to work in.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11989 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-29 06:41:20 +00:00
Chris Lattner
7bcc0e7fff Rename AddUsesToWorkList -> AddUsersToWorkList, as that is what it does.
Create a new AddUsesToWorkList method
optimize memmove/set/cpy of zero bytes to a noop.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11941 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 05:22:00 +00:00
Chris Lattner
6160e85201 Turn 'free null' into nothing
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11940 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-28 04:57:37 +00:00
Chris Lattner
a0ebcebc06 Implement test/Regression/Transforms/InstCombine/canonicalize_branch.ll
This is a really minor thing, but might help out the 'switch statement induction'
code in simplifycfg.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@11900 91177308-0d34-0410-b5e6-96231b3b80d8
2004-02-27 06:27:46 +00:00