llvm-svn: 23348

This is useful for 178.galgel where resolution of dope vectors (by the
optimizer) causes the scales to become apparent.

llvm-svn: 23328

indentation, no functionality change

llvm-svn: 23325

  if () { store A -> P; } else { store B -> P; }

into a PHI node with one store, in the most trival case.  This implements
load.ll:test10.

llvm-svn: 23324

each other.  This implements InstCombine/load.ll:test9

llvm-svn: 23322

load are exactly consequtive.  This is picked up by other passes, but this
triggers thousands of times in fortran programs that use static locals
(and is thus a compile-time speedup).

llvm-svn: 23320

easier to understand?  :)

llvm-svn: 22706

isHighOnes, where it would consider 0 to have high ones.

llvm-svn: 22693

the PHI node, this ugly code can vanish.

llvm-svn: 22672

BasicBlock's removePredecessor routine.  This requires shuffling around
the definition and implementation of hasContantValue from Utils.h,cpp into
Instructions.h,cpp

llvm-svn: 22664

Patch contributed by Jim Laskey!

llvm-svn: 22592

llvm-svn: 22523

explained in the comment.

This fixes UnitTests/2003-09-18-BitFieldTest on darwin

llvm-svn: 22483

as a signed compare.  This patch may fix PR597, but is correct in any case.

llvm-svn: 22465

Because the instcombine has to scan the entire function when it starts up
to begin with, we might as well do it in DFO so we can nuke unreachable code.

This fixes: Transforms/InstCombine/2005-07-07-DeadPHILoop.ll

llvm-svn: 22348

GCC 4.0.0 compiler (sometimes incorrectly) warns about under release build.

llvm-svn: 22249

It is actually always true.  This fixes PR586 and
Transforms/InstCombine/2005-06-16-SetCCOrSetCCMiscompile.ll

llvm-svn: 22236

Transforms/InstCombine/2005-06-16-RangeCrash.ll

llvm-svn: 22234

llvm-svn: 22230

llvm-svn: 22227

llvm-svn: 22225

is always ubyte, get the type being shifted).  This unbreaks espresso

llvm-svn: 22224

Do not perform undefined out of range shifts.

llvm-svn: 22217

allows test programs to succeed. Actual fix for this is forthcoming.

llvm-svn: 22213

fix the bzip2 test. A better hack is needed.

llvm-svn: 22209

llvm-svn: 22192

llvm-svn: 22024

instruction.  This is useful for catching optimizers that don't preserve
calling conventions

llvm-svn: 21928

llvm-svn: 21809

in.  This tends to get cases like this:

  X = cast ubyte to int
  Y = shr int X, ...

Tested by: shift.ll:test24

llvm-svn: 21775

llvm-svn: 21770

llvm-svn: 21737

and.ll:test31

llvm-svn: 21717

the result, turn signed shift rights into unsigned shift rights if possible.

This leads to later simplification and happens *often* in 176.gcc.  For example,
this testcase:

struct xxx { unsigned int code : 8; };
enum codes { A, B, C, D, E, F };
int foo(struct xxx *P) {
  if ((enum codes)P->code == A)
     bar();
}

used to be compiled to:

int %foo(%struct.xxx* %P) {
        %tmp.1 = getelementptr %struct.xxx* %P, int 0, uint 0           ; <uint*> [#uses=1]
        %tmp.2 = load uint* %tmp.1              ; <uint> [#uses=1]
        %tmp.3 = cast uint %tmp.2 to int                ; <int> [#uses=1]
        %tmp.4 = shl int %tmp.3, ubyte 24               ; <int> [#uses=1]
        %tmp.5 = shr int %tmp.4, ubyte 24               ; <int> [#uses=1]
        %tmp.6 = cast int %tmp.5 to sbyte               ; <sbyte> [#uses=1]
        %tmp.8 = seteq sbyte %tmp.6, 0          ; <bool> [#uses=1]
        br bool %tmp.8, label %then, label %UnifiedReturnBlock

Now it is compiled to:

        %tmp.1 = getelementptr %struct.xxx* %P, int 0, uint 0           ; <uint*> [#uses=1]
        %tmp.2 = load uint* %tmp.1              ; <uint> [#uses=1]
        %tmp.2 = cast uint %tmp.2 to sbyte              ; <sbyte> [#uses=1]
        %tmp.8 = seteq sbyte %tmp.2, 0          ; <bool> [#uses=1]
        br bool %tmp.8, label %then, label %UnifiedReturnBlock

which is the difference between this:

foo:
        subl $4, %esp
        movl 8(%esp), %eax
        movl (%eax), %eax
        shll $24, %eax
        sarl $24, %eax
        testb %al, %al
        jne .LBBfoo_2

and this:

foo:
        subl $4, %esp
        movl 8(%esp), %eax
        movl (%eax), %eax
        testb %al, %al
        jne .LBBfoo_2

This occurs 3243 times total in the External tests, 215x in povray,
6x in each f2c'd program, 1451x in 176.gcc, 7x in crafty, 20x in perl,
25x in gap, 3x in m88ksim, 25x in ijpeg.

Maybe this will cause a little jump on gcc tommorow :)

llvm-svn: 21715

llvm-svn: 21713

llvm-svn: 21712

llvm-svn: 21709

This implements set.ll:test20.

This triggers 2x on povray, 9x on mesa, 11x on gcc, 2x on crafty, 1x on eon,
6x on perlbmk and 11x on m88ksim.

It allows us to compile these two functions into the same code:

struct s { unsigned int bit : 1; };
unsigned foo(struct s *p) {
  if (p->bit)
    return 1;
  else
    return 0;
}
unsigned bar(struct s *p) { return p->bit; }

llvm-svn: 21690

llvm-svn: 21647

Implement load.ll:test7

llvm-svn: 21645