code.  Patch by Benjamin Kramer!

llvm-svn: 68885

integer types, unless they are already strange.  This prevents it from
turning the code produced by SROA into crazy libcalls and stuff that 
the code generator can't handle.  In the attached example, the result
was an i96 multiply that caused the x86 backend to assert.

Note that if TargetData had an idea of what the legal types are for
a target that this could be used to stop instcombine from introducing
i64 muls, as Scott wanted.

llvm-svn: 68598

llvm-svn: 68500

llvm-svn: 68485

instead of the place where it started to perform the string copy.

- PR3661
- Patch by Benjamin Kramer!

llvm-svn: 68443

llvm-svn: 68262

  Applications/Burg/burg
  Applications/ClamAV/clamscan
and many other tests.

llvm-svn: 68211

llvm-svn: 68172

if it dangles.

llvm-svn: 68150

Throttle back "fold select into operand" transformation. InstCombine should not generate selects of two constants unless they are selects of 0 and 1.

e.g.
define i32 @t1(i32 %c, i32 %x) nounwind {
       %t1 = icmp eq i32 %c, 0
       %t2 = lshr i32 %x, 18
       %t3 = select i1 %t1, i32 %t2, i32 %x
       ret i32 %t3
}

was turned into

define i32 @t2(i32 %c, i32 %x) nounwind {
       %t1 = icmp eq i32 %c, 0
       %t2 = select i1 %t1, i32 18, i32 0
       %t3 = lshr i32 %x, %t2
       ret i32 %t3
}

For most targets, that means materializing two constants and then a select. e.g. On x86-64

movl    %esi, %eax
shrl    $18, %eax
testl   %edi, %edi
cmovne  %esi, %eax
ret

=>

xorl    %eax, %eax
testl   %edi, %edi
movl    $18, %ecx
cmovne  %eax, %ecx
movl    %esi, %eax
shrl    %cl, %eax
ret

Also, the optimizer and codegen can reason about shl / and / add, etc. by a constant. This optimization will hinder optimizations using ComputeMaskedBits.

llvm-svn: 68142

Patch by Jay Foad.

llvm-svn: 68120

Loop Index Split can eliminate a loop if it can determin if loop body is executed only once. There was a bug in determining IV based value of the iteration for which the loop body is executed. Fix it.

llvm-svn: 68071

a miscompilation.

make[4]: Entering directory `gcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/include'
if [ ! -d "./x86_64-unknown-linux-gnu/bits/stdtr1c++.h.gch" ]; then \
          mkdir -p ./x86_64-unknown-linux-gnu/bits/stdtr1c++.h.gch; \
        fi; \
        gcc-4.2.llvm-objects/./gcc/xgcc -shared-libgcc -Bgcc-4.2.llvm-objects/./gcc -nostdinc++ 
-Lgcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/src -Lgcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/src/.libs 
-B/usr/local/gnat-llvm/x86_64-unknown-linux-gnu/bin/ -B/usr/local/gnat-llvm/x86_64-unknown-linux-gnu/lib/ -isystem 
/usr/local/gnat-llvm/x86_64-unknown-linux-gnu/include -isystem /usr/local/gnat-llvm/x86_64-unknown-linux-gnu/sys-include -Winvalid-pch -Wno-deprecated -x 
c++-header -g -O2  -D_GNU_SOURCE -Igcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/include/x86_64-unknown-linux-gnu 
-Igcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/include -Igcc-4.2.llvm/libstdc++-v3/libsupc++ -O2 -g 
gcc-4.2.llvm/libstdc++-v3/include/precompiled/stdtr1c++.h -o x86_64-unknown-linux-gnu/bits/stdtr1c++.h.gch/O2g.gch
In file included from gcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/include/tr1/repeat.h:247,
                 from gcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/include/tr1/functional:1098,
                 from gcc-4.2.llvm/libstdc++-v3/include/precompiled/stdtr1c++.h:53:
gcc-4.2.llvm-objects/x86_64-unknown-linux-gnu/libstdc++-v3/include/tr1/functional_iterate.h:417: internal compiler error: in ggc_recalculate_in_use_p, at 
ggc-page.c:1602
Please submit a full bug report,
with preprocessed source if appropriate.
See <URL:http://llvm.org/bugs/> for instructions.
make[4]: *** [x86_64-unknown-linux-gnu/bits/stdtr1c++.h.gch/O2g.gch] Error 1

llvm-svn: 67839

llvm-svn: 67811

llvm-svn: 67798

called from llc, not opt, but it's an IR level
optimization nevertheless.)

llvm-svn: 67724

Before deleting a basic block, give other loop passes a chance cleanup analysis values, related to the instructions in the basic block.

llvm-svn: 67719

precise than it used to be.

llvm-svn: 67662

llvm-svn: 67657

to/from integer types that are not intptr_t to convert to intptr_t
then do an integer conversion to the dest type.  This exposes the
cast to the optimizer.

llvm-svn: 67638

1. Make instcombine always canonicalize trunc x to i1 into an icmp(x&1).  This 
   exposes the AND to other instcombine xforms and is more of what the code
   generator expects.
2. Rewrite the remaining trunc pattern match to use 'match', which 
   simplifies it a lot.
   

llvm-svn: 67635

llvm-svn: 67578

explicitly flush it.

llvm-svn: 67526

llvm-svn: 67454

shifts together.  This fixes PR3851.

llvm-svn: 67411

linkage: the value may be replaced with something
different at link time.  (Frontends that want to
allow values to be loaded out of weak constants can
give their constants weak_odr linkage).

llvm-svn: 67407

the inliner; prevents nondeterministic behavior
when the same address is reallocated.
Don't build call graph nodes for debug intrinsic calls;
they're useless, and there were typically a lot of them.

llvm-svn: 67311

llvm-svn: 67307

and was deleting Instructions without clearing the
corresponding map entry.  This led to nondeterministic
behavior if the same address got allocated to another
Instruction within a short time.

llvm-svn: 67306

llvm-svn: 67287

for pointing this out :)

llvm-svn: 67212

llvm-svn: 67211

llvm-svn: 67210

unused loads or bitcasts.

llvm-svn: 67202

If the instruction has no users, it is also not only used by debug info 
and should not be deleted.

llvm-svn: 67194

If I->use_empty(), this method should return false.

llvm-svn: 67180

an invoke instead of after the invoke (in its block), which is invalid.

llvm-svn: 67139

it is not APInt clean, but even when it is it needs to be evaluated carefully
to determine whether it is actually profitable.

This fixes a crash on PR3806

llvm-svn: 67134

llvm-svn: 67089

llvm-svn: 67064