the shifts.
This allows us to fold this (which is the 'integer add a constant' sequence
from cozmic's scheme compmiler):
int %x(uint %anf-temporary776) {
%anf-temporary777 = shr uint %anf-temporary776, ubyte 1
%anf-temporary800 = cast uint %anf-temporary777 to int
%anf-temporary804 = shl int %anf-temporary800, ubyte 1
%anf-temporary805 = add int %anf-temporary804, -2
%anf-temporary806 = or int %anf-temporary805, 1
ret int %anf-temporary806
}
into this:
int %x(uint %anf-temporary776) {
%anf-temporary776 = cast uint %anf-temporary776 to int
%anf-temporary776.mask1 = add int %anf-temporary776, -2
%anf-temporary805 = or int %anf-temporary776.mask1, 1
ret int %anf-temporary805
}
note that instcombine already knew how to eliminate the AND that the two
shifts fold into. This is tested by InstCombine/shift.ll:test26
-Chris
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@25128 91177308-0d34-0410-b5e6-96231b3b80d8
Add support for specifying alignment and size of setjmp jmpbufs.
No targets currently do anything with this information, nor is it presrved
in the bytecode representation. That's coming up next.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24196 91177308-0d34-0410-b5e6-96231b3b80d8
a few times in crafty:
OLD: %tmp.36 = div int %tmp.35, 8 ; <int> [#uses=1]
NEW: %tmp.36 = div uint %tmp.35, 8 ; <uint> [#uses=0]
OLD: %tmp.19 = div int %tmp.18, 8 ; <int> [#uses=1]
NEW: %tmp.19 = div uint %tmp.18, 8 ; <uint> [#uses=0]
OLD: %tmp.117 = div int %tmp.116, 8 ; <int> [#uses=1]
NEW: %tmp.117 = div uint %tmp.116, 8 ; <uint> [#uses=0]
OLD: %tmp.92 = div int %tmp.91, 8 ; <int> [#uses=1]
NEW: %tmp.92 = div uint %tmp.91, 8 ; <uint> [#uses=0]
Which all turn into shrs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24190 91177308-0d34-0410-b5e6-96231b3b80d8
8 times in vortex, allowing the srems to be turned into shrs:
OLD: %tmp.104 = rem int %tmp.5.i37, 16 ; <int> [#uses=1]
NEW: %tmp.104 = rem uint %tmp.5.i37, 16 ; <uint> [#uses=0]
OLD: %tmp.98 = rem int %tmp.5.i24, 16 ; <int> [#uses=1]
NEW: %tmp.98 = rem uint %tmp.5.i24, 16 ; <uint> [#uses=0]
OLD: %tmp.91 = rem int %tmp.5.i19, 8 ; <int> [#uses=1]
NEW: %tmp.91 = rem uint %tmp.5.i19, 8 ; <uint> [#uses=0]
OLD: %tmp.88 = rem int %tmp.5.i14, 8 ; <int> [#uses=1]
NEW: %tmp.88 = rem uint %tmp.5.i14, 8 ; <uint> [#uses=0]
OLD: %tmp.85 = rem int %tmp.5.i9, 1024 ; <int> [#uses=2]
NEW: %tmp.85 = rem uint %tmp.5.i9, 1024 ; <uint> [#uses=0]
OLD: %tmp.82 = rem int %tmp.5.i, 512 ; <int> [#uses=2]
NEW: %tmp.82 = rem uint %tmp.5.i1, 512 ; <uint> [#uses=0]
OLD: %tmp.48.i = rem int %tmp.5.i.i161, 4 ; <int> [#uses=1]
NEW: %tmp.48.i = rem uint %tmp.5.i.i161, 4 ; <uint> [#uses=0]
OLD: %tmp.20.i2 = rem int %tmp.5.i.i, 4 ; <int> [#uses=1]
NEW: %tmp.20.i2 = rem uint %tmp.5.i.i, 4 ; <uint> [#uses=0]
it also occurs 9 times in gcc, but with odd constant divisors (1009 and 61)
so the payoff isn't as great.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@24189 91177308-0d34-0410-b5e6-96231b3b80d8
one use (but one is a cast). This handles the very common case of:
X = alloc [n x byte]
Y = cast X to somethingbetter
seteq X, null
In order to avoid infinite looping when there are multiple casts, we only
allow this if the xform is strictly increasing the alignment of the
allocation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23961 91177308-0d34-0410-b5e6-96231b3b80d8
where the second has less alignment required. If we had explicit alignment
support in the IR, we could handle this case, but we can't until we do.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23960 91177308-0d34-0410-b5e6-96231b3b80d8
This is useful for 178.galgel where resolution of dope vectors (by the
optimizer) causes the scales to become apparent.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23328 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23324 91177308-0d34-0410-b5e6-96231b3b80d8
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).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@23320 91177308-0d34-0410-b5e6-96231b3b80d8
BasicBlock's removePredecessor routine. This requires shuffling around
the definition and implementation of hasContantValue from Utils.h,cpp into
Instructions.h,cpp
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22664 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22348 91177308-0d34-0410-b5e6-96231b3b80d8
It is actually always true. This fixes PR586 and
Transforms/InstCombine/2005-06-16-SetCCOrSetCCMiscompile.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@22236 91177308-0d34-0410-b5e6-96231b3b80d8
in. This tends to get cases like this:
X = cast ubyte to int
Y = shr int X, ...
Tested by: shift.ll:test24
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21775 91177308-0d34-0410-b5e6-96231b3b80d8
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 :)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21715 91177308-0d34-0410-b5e6-96231b3b80d8
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; }
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21690 91177308-0d34-0410-b5e6-96231b3b80d8
Completely rework the 'setcc (cast x to larger), y' code. This code has
the advantage of implementing setcc.ll:test19 (being more general than
the previous code) and being correct in all cases.
This allows us to unxfail 2004-11-27-SetCCForCastLargerAndConstant.ll,
and close PR454.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@21491 91177308-0d34-0410-b5e6-96231b3b80d8
* Properly compile this:
struct a {};
int test() {
struct a b[2];
if (&b[0] != &b[1])
abort ();
return 0;
}
to 'return 0', not abort().
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@19875 91177308-0d34-0410-b5e6-96231b3b80d8
