llvm-svn: 12618

This actually causes us to turn code like:

  return C ? A : B;

into a select instruction.

llvm-svn: 12617

llvm-svn: 12597

llvm-svn: 12595

Testcase: LoopSimplify/2004-04-01-IncorrectDomUpdate.ll

llvm-svn: 12592

llvm-svn: 12573

this and the other patches 253.perlbmk links again.

llvm-svn: 12565

llvm-svn: 12548

pass can eliminate many nasty cases of them, start generating them in the optimizers

llvm-svn: 12545

llvm-svn: 12544

llvm-svn: 12540

llvm-svn: 12520

#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

llvm-svn: 12519

llvm-svn: 12507

With this fix we now successfully extract all 149 loops from 256.bzip2 without
crashing or miscompiling the program!

llvm-svn: 12493

extracted all 63 loops for Olden/bh without crashing and without
miscompiling the program!!!

llvm-svn: 12491

exit nodes

llvm-svn: 12490

llvm-svn: 12489

llvm-svn: 12487

llvm-svn: 12486

1. Names were not put on the new arguments created (ok, this just helps sanity :)
2. Fix outgoing pointer values
3. Do not insert stores for values that had not been computed
4. Fix some wierd problems with the outset calculation

This fixes CodeExtractor/2004-03-14-DominanceProblem.ll, making the extractor
work on at least one simple case!

llvm-svn: 12484

llvm-svn: 12483

exposed the fact that the header was not self-contained.  There is a reason
we do things :)

llvm-svn: 12481

llvm-svn: 12465

llvm-svn: 12464

llvm-svn: 12458

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
}

llvm-svn: 12457

llvm-svn: 12456

testcase from 32.5s in -raise to take .3s

llvm-svn: 12443

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).

llvm-svn: 12442

llvm-svn: 12441

http://mail.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20040308/013095.html

Basically, this patch only updated the immediate dominatees of the header node
to tell them that the preheader also dominated them.  In practice, ALL
dominatees of the header node are also dominated by the preheader.

This fixes: LoopSimplify/2004-03-15-IncorrectDomUpdate.
and PR293

llvm-svn: 12434

horrible hack.

llvm-svn: 12423

llvm-svn: 12420

sin/cos/strlen calls and stuff.  This implements:
  LICM/call_sink_pure_function.ll
  LICM/call_sink_const_function.ll

llvm-svn: 12415

llvm-svn: 12406

Simplify the input/output finder.  All elements of a basic block are
instructions.  Any used arguments are also inputs.  An instruction can only
be used by another instruction.

llvm-svn: 12405

extracted, and a function that contained a single top-level loop never had
the loop extracted, regardless of how much non-loop code there was.

llvm-svn: 12403

* Don't insert a branch to the switch instruction after the call, just
  make it a single block.
* Insert the new alloca instructions in the entry block of the original
  function instead of having them execute dynamically
* Don't make the default edge of the switch instruction go back to the switch.
  The loop extractor shouldn't create new loops!
* Give meaningful names to the alloca slots and the reload instructions
* Some minor code simplifications

llvm-svn: 12402

This also implements a two minor improvements:
  * Don't insert live-out stores IN the region, insert them on the code path
    that exits the region
  * If the region is exited to the same block from multiple paths, share the
    switch statement entry, live-out store code, and the basic block.

llvm-svn: 12401