loop.  This eliminates the extra add from the previous case, but it's
not clear that this will be a performance win overall.  Tommorows test
results will tell. :)

llvm-svn: 13103

types in them.  Instead of creating an induction variable for all types, it
creates a single induction variable and casts to the other sizes.  This generates
this code:

no_exit:                ; preds = %entry, %no_exit
        %indvar = phi uint [ %indvar.next, %no_exit ], [ 0, %entry ]            ; <uint> [#uses=4]
***     %j.0.0 = cast uint %indvar to short             ; <short> [#uses=1]
        %indvar = cast uint %indvar to int              ; <int> [#uses=1]
        %tmp.7 = getelementptr short* %P, uint %indvar          ; <short*> [#uses=1]
        store short %j.0.0, short* %tmp.7
        %inc.0 = add int %indvar, 1             ; <int> [#uses=2]
        %tmp.2 = setlt int %inc.0, %N           ; <bool> [#uses=1]
        %indvar.next = add uint %indvar, 1              ; <uint> [#uses=1]
        br bool %tmp.2, label %no_exit, label %loopexit

instead of:

no_exit:                ; preds = %entry, %no_exit
        %indvar = phi ushort [ %indvar.next, %no_exit ], [ 0, %entry ]          ; <ushort> [#uses=2]
***     %indvar = phi uint [ %indvar.next, %no_exit ], [ 0, %entry ]            ; <uint> [#uses=3]
        %indvar = cast uint %indvar to int              ; <int> [#uses=1]
        %indvar = cast ushort %indvar to short          ; <short> [#uses=1]
        %tmp.7 = getelementptr short* %P, uint %indvar          ; <short*> [#uses=1]
        store short %indvar, short* %tmp.7
        %inc.0 = add int %indvar, 1             ; <int> [#uses=2]
        %tmp.2 = setlt int %inc.0, %N           ; <bool> [#uses=1]
        %indvar.next = add uint %indvar, 1
***     %indvar.next = add ushort %indvar, 1
        br bool %tmp.2, label %no_exit, label %loopexit

This is an improvement in register pressure, but probably doesn't happen that
often.

The more important fix will be to get rid of the redundant add.

llvm-svn: 13101

structure to being dynamically computed on demand.  This makes updating
loop information MUCH easier.

llvm-svn: 13045

exit values.

llvm-svn: 13018

the trip count for the loop, insert one so that we can canonicalize the exit
condition.

llvm-svn: 13015

llvm-svn: 12980

the back-edge block, we must check the preincremented value.

llvm-svn: 12968

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.

llvm-svn: 12961

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.

llvm-svn: 12620

getSubLoops/getTopLevelLoops methods, replacing them with iterator-based
accessors.

llvm-svn: 10714

it doesn't do anything with it.

llvm-svn: 10590

contains no functionality changes.

llvm-svn: 10583

arithmetic into "array subscripts"

llvm-svn: 10580

llvm-svn: 10573

according to the CVS log messages.

llvm-svn: 10517

llvm-svn: 10516

llvm-svn: 10473

llvm-svn: 10385

Reorder #includes
Implement: IndVarsSimplify/2003-12-10-IndVarDeadCode.ll

llvm-svn: 10376

llvm-svn: 9903

Header files will be on the way.

llvm-svn: 9298

llvm-svn: 9061

llvm-svn: 9027

llvm-svn: 8689

llvm-svn: 8502

be the canonical form for the word

llvm-svn: 8430

llvm-svn: 8428

llvm-svn: 7492

llvm-svn: 5872

    setPreservesCFG to be less confusing.

llvm-svn: 4255

    * Renamed StatisticReporter.h/cpp to Statistic.h/cpp
    * Broke constructor to take two const char * arguments instead of one, so
      that indendation can be taken care of automatically.
    * Sort the list by pass name when printing
    * Make sure to print all statistics as a group, instead of randomly when
      the statistics dtors are called.
    * Updated ProgrammersManual with new semantics.

llvm-svn: 4002

of instruction constructors.

llvm-svn: 3656

* Fix bug: test/Regression/Transforms/IndVarsSimplify/2002-09-09-PointerIndVar.ll

llvm-svn: 3644

- Cleaned up the interface to AnalysisUsage to take analysis class names
   instead of ::ID's.
 - Pass::getAnalysis<> now no longer takes an optional argument

llvm-svn: 3265

  methods
* Eliminate AnalysisID:  Now it is just a typedef for const PassInfo*
* Simplify how AnalysisID's are initialized
* Eliminate Analysis/Writer.cpp/.h: incorporate printing functionality into
  the analyses themselves.

llvm-svn: 3116

* Add support for different "PassType's"
* Add new RegisterOpt/RegisterAnalysis templates for registering passes that
  are to show up in opt or analyze
* Register Analyses now
* Change optimizations to use RegisterOpt instead of RegisterPass
* Add support for different "PassType's"
* Add new RegisterOpt/RegisterAnalysis templates for registering passes that
  are to show up in opt or analyze
* Register Analyses now
* Change optimizations to use RegisterOpt instead of RegisterPass
* Remove getPassName implementations from various subclasses

llvm-svn: 3113

llvm-svn: 3016

llvm-svn: 2813

llvm-svn: 2792

For details, See: docs/2002-06-25-MegaPatchInfo.txt

llvm-svn: 2779