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: 22206

llvm-svn: 22192

llvm-svn: 22024

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

llvm-svn: 21928

fixes Ptrdist/anagram with x86 llcbeta

llvm-svn: 21925

llvm-svn: 21924

llvm-svn: 21839

suitable for tail calls.

llvm-svn: 21836

llvm-svn: 21809

llvm-svn: 21788

llvm-svn: 21786

llvm-svn: 21785

This makes reassociate realize that loads should be treated as unmovable, and
gives distinct ranks to distinct values defined in the same basic block, allowing
reassociate to do its thing.

llvm-svn: 21783

llvm-svn: 21781

llvm-svn: 21780

llvm-svn: 21778

llvm-svn: 21776

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: 21772

llvm-svn: 21771

llvm-svn: 21770

of trying to do local reassociation tweaks at each level, only process an expression
tree once (at its root).  This does not improve the reassociation pass in any real way.

llvm-svn: 21768

Reassociate/shifttest.ll

llvm-svn: 21761

llvm-svn: 21759

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: 21653

llvm-svn: 21647

Implement load.ll:test7

llvm-svn: 21645

llvm-svn: 21565

llvm-svn: 21541

llvm-svn: 21500