The common code in the post-RA scheduler to break anti-dependencies on the
critical path contained a flaw. In the reported case, an anti-dependency
between the overlapping registers %X4 and %R4 exists:
%X29<def> = OR8 %X4, %X4
%R4<def>, %X3<def,dead,tied3> = LBZU 1, %X3<kill,tied1>
The unpatched code breaks the dependency by replacing %R4 and its uses
with %R3, the first register on the available list. However, %R3 and
%X3 overlap, so this creates two overlapping definitions on the same
instruction.
The fix is straightforward, preventing selection of a register that
overlaps any other defined register on the same instruction.
The test case is reduced from the bug report, and verifies that we no
longer produce "lbzu 3, 1(3)" when breaking this anti-dependency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173706 91177308-0d34-0410-b5e6-96231b3b80d8
It is way too slow. Change the default option value to 0.
Always do exact shadow propagation for unsigned ICmp with constants, it is
cheap (under 1% cpu time) and required for correctness.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173682 91177308-0d34-0410-b5e6-96231b3b80d8
Fix that by adding a cast to the shift expander. This came up with vector shifts
on sse-less X86 CPUs.
<2 x i64> = shl <2 x i64> <2 x i64>
-> i64,i64 = shl i64 i64; shl i64 i64
-> i32,i32,i32,i32 = shl_parts i32 i32 i64; shl_parts i32 i32 i64
Now we cast the last two i64s to the right type. Fixes the crash in PR14668.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173615 91177308-0d34-0410-b5e6-96231b3b80d8
This adds support for LLVM to accept metadata that doesn't include a top level
lexical block in a function. Specifically LLVM couldn't handle this when there
were file changes relating to these blocks. I've updated a few test cases to
ensure other functionality (such as inlining) isn't affected by this change, but
haven't pervasively updated all the test cases.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173592 91177308-0d34-0410-b5e6-96231b3b80d8
This catches many cases where we can emit a more efficient shuffle for a
specific mask or when the mask contains undefs. Once the splat is lowered to
unpacks we can't do that anymore.
There is a possibility of moving the promotion after pshufb matching, but I'm
not sure if pshufb with a mask loaded from memory is faster than 3 shuffles, so
I avoided that for now.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173569 91177308-0d34-0410-b5e6-96231b3b80d8
This provides a place to add customized operation cost information and
control some other target-specific IR-level transformations.
The only non-trivial logic in this checkin assigns a higher cost to
unaligned loads and stores (covered by the included test case).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173520 91177308-0d34-0410-b5e6-96231b3b80d8
The test runner does not rewrite instances of /dev/null inside the
quoted sh command. /dev/null does not exist, so opt will fail to open
it, and return a non-zero exit code.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173509 91177308-0d34-0410-b5e6-96231b3b80d8
Cygwin git-svn will faithfully forward the svn properties all the way
down to the NTFS executable permission. Without the +x bit, tests using
these scripts fail with "Access Denied".
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173508 91177308-0d34-0410-b5e6-96231b3b80d8
These tests in particular try to use escaped square brackets as an
argument to grep, which is failing for me with native win32 python. It
appears the backslash is being lost near the CreateProcess*() call.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173506 91177308-0d34-0410-b5e6-96231b3b80d8
(defined by the x32 ABI) mode, in which case its pointers are 32-bits
in size. This knowledge is also added to X86RegisterInfo that now
returns the appropriate registers in getPointerRegClass.
There are many outcomes to this change. In order to keep the patches
separate and manageable, we start by focusing on some simple testable
cases. The patch adds a test with passing a pointer to a function -
focusing on the difference between the two data models for x86-64.
Another test is added for handling of 'sret' arguments (and
functionality is added in X86ISelLowering to make it work).
A note on naming: the "x32 ABI" document refers to the AMD64
architecture (in LLVM it's distinguished by being is64Bits() in the
x86 subtarget) with two variations: the LP64 (default) data model, and
the ILP32 data model. This patch adds predicates to the subtarget
which are consistent with this naming scheme.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173503 91177308-0d34-0410-b5e6-96231b3b80d8
Only for integers, pointers, and vectors of those. No floats.
Instrumentation seems very heavy, and may need to be replaced
with some approximation in the future.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173452 91177308-0d34-0410-b5e6-96231b3b80d8
This adds an !add(a, b) operator to tablegen; this will be used
to cleanup the PPC register definitions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173445 91177308-0d34-0410-b5e6-96231b3b80d8
Allow the strategy to select SchedDFS. Allow the results of SchedDFS
to affect initialization of the scheduler state.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173425 91177308-0d34-0410-b5e6-96231b3b80d8
loops over instructions in the basic block or the use-def list of the
value, neither of which are really efficient when repeatedly querying
about values in the same basic block.
What's more, we already know that the CondBB is small, and so we can do
a much more efficient test by counting the uses in CondBB, and seeing if
those account for all of the uses.
Finally, we shouldn't blanket fail on any such instruction, instead we
should conservatively assume that those instructions are part of the
cost.
Note that this actually fixes a bug in the pass because
isUsedInBasicBlock has a really terrible bug in it. I'll fix that in my
next commit, but the fix for it would make this code suddenly take the
compile time hit I thought it already was taking, so I wanted to go
ahead and migrate this code to a faster & better pattern.
The bug in isUsedInBasicBlock was also causing other tests to test the
wrong thing entirely: for example we weren't actually disabling
speculation for floating point operations as intended (and tested), but
the test passed because we failed to speculate them due to the
isUsedInBasicBlock failure.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173417 91177308-0d34-0410-b5e6-96231b3b80d8
Original commit message:
Plug TTI into the speculation logic, giving it a real cost interface
that can be specialized by targets.
The goal here is not to be more aggressive, but to just be more accurate
with very obvious cases. There are instructions which are known to be
truly free and which were not being modeled as such in this code -- see
the regression test which is distilled from an inner loop of zlib.
Everywhere the TTI cost model is insufficiently conservative I've added
explicit checks with FIXME comments to go add proper modelling of these
cost factors.
If this causes regressions, the likely solution is to make TTI even more
conservative in its cost estimates, but test cases will help here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173357 91177308-0d34-0410-b5e6-96231b3b80d8
We use constant folding to see if an intrinsic evaluates to the same value as a
constant that we know. If we don't take the undefinedness into account we get a
value that doesn't match the actual implementation, and miscompiled code.
This was uncovered by Chandler's simplifycfg changes.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173356 91177308-0d34-0410-b5e6-96231b3b80d8
that can be specialized by targets.
The goal here is not to be more aggressive, but to just be more accurate
with very obvious cases. There are instructions which are known to be
truly free and which were not being modeled as such in this code -- see
the regression test which is distilled from an inner loop of zlib.
Everywhere the TTI cost model is insufficiently conservative I've added
explicit checks with FIXME comments to go add proper modelling of these
cost factors.
If this causes regressions, the likely solution is to make TTI even more
conservative in its cost estimates, but test cases will help here.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173342 91177308-0d34-0410-b5e6-96231b3b80d8
a cost fuction that seems both a bit ad-hoc and also poorly suited to
evaluating constant expressions.
Notably, it is missing any support for trivial expressions such as
'inttoptr'. I could fix this routine, but it isn't clear to me all of
the constraints its other users are operating under.
The core protection that seems relevant here is avoiding the formation
of a select instruction wich a further chain of select operations in
a constant expression operand. Just explicitly encode that constraint.
Also, update the comments and organization here to make it clear where
this needs to go -- this should be driven off of real cost measurements
which take into account the number of constants expressions and the
depth of the constant expression tree.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173340 91177308-0d34-0410-b5e6-96231b3b80d8
Allow Mips16 routines to call Mips32 routines that have abi requirements
that either arguments or return values are passed in floating point
registers. This handles only the pic case. We have not done non pic
for Mips16 yet in any form.
The libm functions are Mips32, so with this addition we have a complete
Mips16 hard float implementation.
We still are not able to complete mix Mip16 and Mips32 with hard float.
That will be the next phase which will have several steps. For Mips32
to freely call Mips16 some stub functions must be created.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173320 91177308-0d34-0410-b5e6-96231b3b80d8
The requirements of the strong heuristic are:
* A Protector is required for functions which contain an array, regardless of
type or length.
* A Protector is required for functions which contain a structure/union which
contains an array, regardless of type or length. Note, there is no limit to
the depth of nesting.
* A protector is required when the address of a local variable (i.e., stack
based variable) is exposed. (E.g., such as through a local whose address is
taken as part of the RHS of an assignment or a local whose address is taken as
part of a function argument.)
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173231 91177308-0d34-0410-b5e6-96231b3b80d8
SSPStrong applies a heuristic to insert stack protectors in these situations:
* A Protector is required for functions which contain an array, regardless of
type or length.
* A Protector is required for functions which contain a structure/union which
contains an array, regardless of type or length. Note, there is no limit to
the depth of nesting.
* A protector is required when the address of a local variable (i.e., stack
based variable) is exposed. (E.g., such as through a local whose address is
taken as part of the RHS of an assignment or a local whose address is taken as
part of a function argument.)
This patch implements the SSPString attribute to be equivalent to
SSPRequired. This will change in a subsequent patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@173230 91177308-0d34-0410-b5e6-96231b3b80d8