When the least bit of C is greater than V, (x&C) must be greater than V
if it is not zero, so the comparison can be simplified.
Although this was suggested in Target/X86/README.txt, it benefits any
architecture with a directly testable form of AND.
Patch by Kevin Schoedel
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170576 91177308-0d34-0410-b5e6-96231b3b80d8
This assumes (1 << n) is always not zero. Consider n is greater than word size.
Although I know it is undefined, this transforms undefined behavior hidden.
This led clang unexpected behavior with some failures. I will investigate to fix undefined shl in clang.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@170128 91177308-0d34-0410-b5e6-96231b3b80d8
This change attempts to simplify (X^Y) -> X or Y in the user's context if we know that
only bits from X or Y are demanded.
A minimized case is provided bellow. This change will simplify "t>>16" into "var1 >>16".
=============================================================
unsigned foo (unsigned val1, unsigned val2) {
unsigned t = val1 ^ 1234;
return (t >> 16) | t; // NOTE: t is used more than once.
}
=============================================================
Note that if the "t" were used only once, the expression would be finally optimized as well.
However, with with this change, the optimization will take place earlier.
Reviewed by Nadav, Thanks a lot!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169317 91177308-0d34-0410-b5e6-96231b3b80d8
The type of shirt-right (logical or arithemetic) should remain unchanged
when transforming "X << C1 >> C2" into "X << (C1-C2)"
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@169209 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the puts optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
All the simplifiers from simplify-libcalls have now been migrated to
instcombine. Yay! Just a few other bits to migrate (prototype attribute
inference and a few statistics) and simplify-libcalls can finally be put
to rest.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168925 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the fputs optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168893 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the fwrite optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168892 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the fprintf optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168891 91177308-0d34-0410-b5e6-96231b3b80d8
My commit to migrate the printf simplifiers from the simplify-libcalls
in r168604 introduced a regression reported by Duncan [1]. The problem
is that in some cases the library call simplifier can return a new value
that has no uses and the new value's type is different than the old value's
type (which is fine because there are no uses). The specific case that
triggered the bug looked something like:
declare void @printf(i8*, ...)
...
call void (i8*, ...)* @printf(i8* %fmt)
Which we want to optimized into:
call i32 @putchar(i32 104)
However, the code was attempting to replace all uses of the printf with
the putchar and the types differ, hence a crash. This is fixed by *just*
deleting the original instruction when there are no uses. The old
simplify-libcalls pass is already doing something similar.
[1] http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-November/056338.html
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168716 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the sprintf optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168677 91177308-0d34-0410-b5e6-96231b3b80d8
InstCombineLoadStoreAlloca.cpp, which had many issues.
(At least two bugs were noted on llvm-commits, and it was overly conservative.)
Instead, use getOrEnforceKnownAlignment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168629 91177308-0d34-0410-b5e6-96231b3b80d8
Enhancement to InstCombine. Try to catch this opportunity:
---------------------------------------------------------------
((X^C1) >> C2) ^ C3 => (X>>C2) ^ ((C1>>C2)^C3)
where the subexpression "X ^ C1" has more than one uses, and
"(X^C1) >> C2" has single use.
----------------------------------------------------------------
Reviewed by Nadav (with minor change per his request).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168615 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the printf optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168604 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the toascii optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168580 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the isascii optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168579 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the isdigit optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168578 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the *abs optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168574 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the ffs* optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168571 91177308-0d34-0410-b5e6-96231b3b80d8
I discovered a few more missing functions while migrating optimizations
from the simplify-libcalls pass to the instcombine (I already added some
in r167659).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168501 91177308-0d34-0410-b5e6-96231b3b80d8
"not grep '-715827882'" performed as below...bad...
Usage: grep [OPTION]... PATTERN [FILE]...
Try `grep --help' for more information.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168430 91177308-0d34-0410-b5e6-96231b3b80d8
replaced by this patch is equivalent to the new logic, but you'd be wrong, and
that's exactly where the bug was. There's a similar bug in instsimplify which
manifests itself as instsimplify failing to simplify this, rather than doing it
wrong, see next commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168181 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the math library call simplifications from the
simplify-libcalls pass into the instcombine library call simplifier.
I have typically migrated just one simplifier at a time, but the math
simplifiers are interdependent because:
1. CosOpt, PowOpt, and Exp2Opt all depend on UnaryDoubleFPOpt.
2. CosOpt, PowOpt, Exp2Opt, and UnaryDoubleFPOpt all depend on
the option -enable-double-float-shrink.
These two factors made migrating each of these simplifiers individually
more of a pain than it would be worth. So, I migrated them all together.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167815 91177308-0d34-0410-b5e6-96231b3b80d8
The library call simplifier folds memcmp calls with all constant arguments
to a constant. For example:
memcmp("foo", "foo", 3) -> 0
memcmp("hel", "foo", 3) -> 1
memcmp("foo", "hel", 3) -> -1
The folding is implemented in terms of the system memcmp that LLVM gets
linked with. It currently just blindly uses the value returned from
the system memcmp as the folded constant.
This patch normalizes the values returned from the system memcmp to
(-1, 0, 1) so that we get consistent results across multiple platforms.
The test cases were adjusted accordingly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167726 91177308-0d34-0410-b5e6-96231b3b80d8
Transforms/InstCombine/memcmp-1.ll has a test case that looks like:
@foo = constant [4 x i8] c"foo\00"
@hel = constant [4 x i8] c"hel\00"
...
%mem1 = getelementptr [4 x i8]* @hel, i32 0, i32 0
%mem2 = getelementptr [4 x i8]* @foo, i32 0, i32 0
%ret = call i32 @memcmp(i8* %mem1, i8* %mem2, i32 3)
ret i32 %ret
; CHECK: ret i32 2
The folded return value (2 above) is computed using the system memcmp
that the compiler is linked with. This can return different values on
different systems. The test was originally written on an OS X 10.7.5
x86-64 box and passed. However, it failed on one of the x86-64 FreeBSD
buildbots because the system memcpy on that machine returned a different
value (1 instead of 2).
I fixed the test by checking the folding constants with regexes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167691 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the memset optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167689 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the memmove optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167687 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the memcpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167686 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the memcmp optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167683 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strstr optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167682 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strcspn optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167675 91177308-0d34-0410-b5e6-96231b3b80d8
Several of the simplifiers migrated from the simplify-libcalls pass to
the instcombine pass were not correctly checking the target library
information to gate the simplifications. This patch ensures that the
check is made.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167660 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strspn optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167568 91177308-0d34-0410-b5e6-96231b3b80d8
getIntPtrType support for multiple address spaces via a pointer type,
and also introduced a crasher bug in the constant folder reported in
PR14233.
These commits also contained several problems that should really be
addressed before they are re-committed. I have avoided reverting various
cleanups to the DataLayout APIs that are reasonable to have moving
forward in order to reduce the amount of churn, and minimize the number
of commits that were reverted. I've also manually updated merge
conflicts and manually arranged for the getIntPtrType function to stay
in DataLayout and to be defined in a plausible way after this revert.
Thanks to Duncan for working through this exact strategy with me, and
Nick Lewycky for tracking down the really annoying crasher this
triggered. (Test case to follow in its own commit.)
After discussing with Duncan extensively, and based on a note from
Micah, I'm going to continue to back out some more of the more
problematic patches in this series in order to ensure we go into the
LLVM 3.2 branch with a reasonable story here. I'll send a note to
llvmdev explaining what's going on and why.
Summary of reverted revisions:
r166634: Fix a compiler warning with an unused variable.
r166607: Add some cleanup to the DataLayout changes requested by
Chandler.
r166596: Revert "Back out r166591, not sure why this made it through
since I cancelled the command. Bleh, sorry about this!
r166591: Delete a directory that wasn't supposed to be checked in yet.
r166578: Add in support for getIntPtrType to get the pointer type based
on the address space.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167221 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strto* optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167119 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strpbrk optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167105 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strlen optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167103 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strncpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167102 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the stpcpy optimizations from the simplify-libcalls
pass into the instcombine library call simplifier. Note that the
__stpcpy_chk simplifications were migrated in a previous commit.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167083 91177308-0d34-0410-b5e6-96231b3b80d8
r166198 migrated the strcpy optimization to instcombine. The strcpy
simplifier that was migrated from Transforms/Scalar/SimplifyLibCalls.cpp
was also doing some __strcpy_chk simplifications. Those fortified
simplifications were migrated as well, but introduced a bug in the
__stpcpy_chk simplifier in the process. This happened because the
__strcpy_chk and __stpcpy_chk simplifiers were both mapped to StrCpyChkOpt
which was updated with simplifications that worked for __strcpy_chk, but
not __stpcpy_chk.
This patch fixes the problem by adding proper test coverage and creating a
new simplifier for __stpcpy_chk (instead of sharing one with __strcpy_chk).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@167082 91177308-0d34-0410-b5e6-96231b3b80d8
%V = mul i64 %N, 4
%t = getelementptr i8* bitcast (i32* %arr to i8*), i32 %V
into
%t1 = getelementptr i32* %arr, i32 %N
%t = bitcast i32* %t1 to i8*
incorporating the multiplication into the getelementptr.
This happens all the time in dragonegg, for example for
int foo(int *A, int N) {
return A[N];
}
because gcc turns this into byte pointer arithmetic before it hits the plugin:
D.1590_2 = (long unsigned int) N_1(D);
D.1591_3 = D.1590_2 * 4;
D.1592_5 = A_4(D) + D.1591_3;
D.1589_6 = *D.1592_5;
return D.1589_6;
The D.1592_5 line is a POINTER_PLUS_EXPR, which is turned into a getelementptr
on a bitcast of A_4 to i8*, so this becomes exactly the kind of IR that the
transform fires on.
An analogous transform (with no testcases!) already existed for bitcasts of
arrays, so I rewrote it to share code with this one.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166474 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strcpy optimizations from the simplify-libcalls pass
into the instcombine library call simplifier. Note also that StrCpyChkOpt
has been updated with a few simplifications that were being done in the
simplify-libcalls version of StrCpyOpt, but not in the migrated implementation
of StrCpyOpt. There is no reason to overload StrCpyOpt with fortified and
regular simplifications in the new model since there is already a dedicated
simplifier for __strcpy_chk.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166198 91177308-0d34-0410-b5e6-96231b3b80d8
An obfuscated splat is where the frontend poorly generates code for a splat
using several different shuffles to create the splat, i.e.,
%A = load <4 x float>* %in_ptr, align 16
%B = shufflevector <4 x float> %A, <4 x float> undef, <4 x i32> <i32 0, i32 0, i32 undef, i32 undef>
%C = shufflevector <4 x float> %B, <4 x float> %A, <4 x i32> <i32 0, i32 1, i32 4, i32 undef>
%D = shufflevector <4 x float> %C, <4 x float> %A, <4 x i32> <i32 0, i32 1, i32 2, i32 4>
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166061 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strcmp and strncmp optimizations from the
simplify-libcalls pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165915 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strchr and strrchr optimizations from the
simplify-libcalls pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165875 91177308-0d34-0410-b5e6-96231b3b80d8
This patch migrates the strcat and strncat optimizations from the
simplify-libcalls pass into the instcombine library call simplifier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@165874 91177308-0d34-0410-b5e6-96231b3b80d8
