Patch by Michele Scandale!
Rewrite of the functions used to compute the backedge taken count of a
loop on LT and GT comparisons.
I decided to split the handling of LT and GT cases becasue the trick
"a > b == -a < -b" in some cases prevents the trip count computation
due to the multiplication by -1 on the two operands of the
comparison. This issue comes from the conservative computation of
value range of SCEVs: taking the negative SCEV of an expression that
have a small positive range (e.g. [0,31]), we would have a SCEV with a
fullset as value range.
Indeed, in the new rewritten function I tried to better handle the
maximum backedge taken count computation when MAX/MIN expression are
used to handle the cases where no entry guard is found.
Some test have been modified in order to check the new value correctly
(I manually check them and reasoning on possible overflow the new
values seem correct).
I finally added a new test case related to the multiplication by -1
issue on GT comparisons.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194116 91177308-0d34-0410-b5e6-96231b3b80d8
MorphNodeTo is not safe to call during DAG building. It eagerly
deletes dependent DAG nodes which invalidates the NodeMap. We could
expose a safe interface for morphing nodes, but I don't think it's
worth it. Just create a new MachineNode and replaceAllUsesWith.
My understaning of the SD design has been that we want to support
early target opcode selection. That isn't very well supported, but
generally works. It seems reasonable to rely on this feature even if
it isn't widely used.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194102 91177308-0d34-0410-b5e6-96231b3b80d8
Cortex-M0 supports these 32-bit instructions despite being Thumb1 only
(mostly). We knew about that but not that the aliases without the default "sy"
operand were also permitted.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194094 91177308-0d34-0410-b5e6-96231b3b80d8
Due to the previously added overflow checks, we can have a retain/release
relation that is one directional. This occurs specifically when we run into an
additive overflow causing us to drop state in only one direction. If that
occurs, we should bail and not optimize that retain/release instead of
asserting.
Apologies for the size of the testcase. It is necessary to cause the additive
cfg overflow to trigger.
rdar://15377890
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194083 91177308-0d34-0410-b5e6-96231b3b80d8
Submit the basic port of the rest of ARM constant islands code to Mips.
Two test cases are added which reflect the next level of functionality:
constants getting moved to water areas that are out of range from the
initial placement at the end of the function and basic blocks being split to
create water when none exists that can be used. There is a bunch of this
code that is not complete and has been marked with IN_PROGRESS. I will
finish cleaning this all up during the next week or two and submit the
rest of the test cases. I have elminated some code for dealing with
inline assembly because to me it unecessarily complicates things and
some of the newer features of llvm like function attributies and builtin
assembler give me better tools to solve the alignment issues created
there. Also, for Mips16 I even have the option of not doing constant
islands in the present of inline assembler if I chose. When everything
has been completed I will summarize the port and notify people that
are knowledgable regarding the ARM Constant Islands code so they can
review it in it's entirety if they wish.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194053 91177308-0d34-0410-b5e6-96231b3b80d8
If an inline assembly operand has multiple constraints (e.g. "Ir" for immediate
or register) and an operand modifier (E.g. "w" for "print register as wN") then
we need to decide behaviour when the modifier doesn't apply to the constraint.
Previousely produced some combination of an assertion failure and a fatal
error. GCC's behaviour appears to be to ignore the modifier and print the
operand in the default way. This patch should implement that.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194024 91177308-0d34-0410-b5e6-96231b3b80d8
When the elements are extracted from a select on vectors
or a vector select, do the select on the extracted scalars
from the input if there is only one use.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@194013 91177308-0d34-0410-b5e6-96231b3b80d8
In order to create an ObjectFile implementation that uses bitcode files, we
need to propagate the bitcode errors to the ObjectFile interface, so we need
to convert it to use the same error handling as ObjectFile: error_code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193996 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r193356, it caused PR17781.
A reduced test case covering this regression has been added to the test suite.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193955 91177308-0d34-0410-b5e6-96231b3b80d8
This adds an SimplifyLibCalls case which converts the special __sinpi and
__cospi (float & double variants) into a __sincospi_stret where appropriate to
remove duplicated work.
Patch by Tim Northover
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193943 91177308-0d34-0410-b5e6-96231b3b80d8
There is still a long way to go for llvm-nm, but at least we now match
nm's letter output in the cases we test for.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193912 91177308-0d34-0410-b5e6-96231b3b80d8
- When selecting BLEND from vselect, the operands need swapping as due to the
difference between vselect and SSE/AVX's BLEND insn
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193900 91177308-0d34-0410-b5e6-96231b3b80d8
I hit some problems with future work due to the member subprogram of
'a_b's type having a subprogram (an implicit default ctor, !52 in the
pre-commit source) with no name. Clang now generates a name for such a
function but in this case doesn't even emit debug info for it as it is
unused (Clang never emits the body of the ctor, instead just emitting
memset if needed).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@193892 91177308-0d34-0410-b5e6-96231b3b80d8
