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.
llvm-svn: 167726
This is the second and last (2/2) part of a change that moves llvm-symbolizer to llvm/tools/, which will allow to build it
with both cmake and configure+make.
llvm-svn: 167723
Each SM and PTX version is modeled as a subtarget feature/CPU. Additionally,
PTX 3.1 is added as the default PTX version to be out-of-the-box compatible
with CUDA 5.0.
Available CPUs for this target:
sm_10 - Select the sm_10 processor.
sm_11 - Select the sm_11 processor.
sm_12 - Select the sm_12 processor.
sm_13 - Select the sm_13 processor.
sm_20 - Select the sm_20 processor.
sm_21 - Select the sm_21 processor.
sm_30 - Select the sm_30 processor.
sm_35 - Select the sm_35 processor.
Available features for this target:
ptx30 - Use PTX version 3.0.
ptx31 - Use PTX version 3.1.
sm_10 - Target SM 1.0.
sm_11 - Target SM 1.1.
sm_12 - Target SM 1.2.
sm_13 - Target SM 1.3.
sm_20 - Target SM 2.0.
sm_21 - Target SM 2.1.
sm_30 - Target SM 3.0.
sm_35 - Target SM 3.5.
llvm-svn: 167699
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.
llvm-svn: 167691
In some cases the library call simplifier may need to replace instructions
other than the library call being simplified. In those cases it may be
necessary for clients of the simplifier to override how the replacements
are actually done. As such, a new overrideable method for replacing
instructions was added to LibCallSimplifier.
A new subclass of LibCallSimplifier is also defined which overrides
the instruction replacement method. This is because the instruction
combiner defines its own replacement method which updates the worklist
when instructions are replaced.
llvm-svn: 167681
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.
llvm-svn: 167660
In the process of migrating optimizations from the simplify-libcalls pass
to the instcombine pass I noticed that a few functions are missing from
the target library information. These functions need to be available for
querying in the instcombine library call simplifiers. More functions will
probably be added in the future as more simplifiers are migrated to
instcombine.
llvm-svn: 167659
mov lr, pc
b.w _foo
The "mov" instruction doesn't set bit zero to one, it's putting incorrect
value in lr. It messes up backtraces.
rdar://12663632
llvm-svn: 167657
The RegMaskSlots contains 'r' slots while NewIdx and OldIdx are 'B'
slots. This broke the checks in the assertions.
This fixes PR14302.
llvm-svn: 167625
