The 0x66 prefix toggles between 16-bit and 32-bit addressing mode.
So in 32-bit mode it is used to switch to 16-bit addressing mode for the
following instruction, while in 16-bit mode it's the other way round — it's
used to switch to 32-bit mode instead.
Thus, emit the 0x66 prefix byte for OpSize only in 32-bit (and 64-bit) mode,
and introduce a new OpSize16 bit which is used in 16-bit mode instead.
This is just the basic infrastructure for that change; a subsequent patch
will add the new OpSize16 bit to the 32-bit instructions that need it.
Patch from David Woodhouse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198586 91177308-0d34-0410-b5e6-96231b3b80d8
This is not really expected to work right yet. Mostly because we will
still emit the OpSize (0x66) prefix in all the wrong places, along with
a number of other corner cases. Those will all be fixed in the subsequent
commits.
Patch from David Woodhouse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198584 91177308-0d34-0410-b5e6-96231b3b80d8
There is a wrong assumption that the vector element type and the
type of each ConstantSDNode in the build_vector were the same.
However, when promoting the integer operand of a legally typed
build_vector, the operand type and the vector element type do not
need to be the same
(See method 'DAGTypeLegalizer::PromoteIntOp_BUILD_VECTOR' in
LegalizeIntegerTypes.cpp).
in AArch64 backend, the following dag sequence:
C0: i1 = Constant<0>
C1: i1 = Constant<-1>
V: v8i1 = BUILD_VECTOR C1, C1, C0, C0, C0, C0, C0, C0
is type-legalized into:
NewC0: i32 = Constant<0>
NewC1: i32 = Constant<1>
V: v8i8 = BUILD_VECTOR NewC1, NewC1, NewC0, NewC0, NewC0, NewC0, NewC0, NewC0
Forcing a getZeroExtend to VTBits to ensure that the new constant
is correctly.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198582 91177308-0d34-0410-b5e6-96231b3b80d8
This moves the check up into the parent class so that all targets can use it
without having to copy (and keep in sync) the same error message.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198579 91177308-0d34-0410-b5e6-96231b3b80d8
Move the ARM EHABI unwind opcode definitions from the ARM MCTargetDesc into LLVM
Support. This enables sharing of the definitions across the ARM target code as
well as llvm-readobj. This will allow implementation of the unwind decoding in
llvm-readobj.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198576 91177308-0d34-0410-b5e6-96231b3b80d8
Add some tests to validate correct register selection, including a fix
to an existing test which was requiring the *wrong* output.
Patch from David Woodhouse.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198566 91177308-0d34-0410-b5e6-96231b3b80d8
Removed vzeroupper from AVX-512 mode - our optimization gude does not recommend to insert vzeroupper at all.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198557 91177308-0d34-0410-b5e6-96231b3b80d8
Missed this when adding the skeleton analysis. Caught by a build break
in the next patch I'm working on when trying to use the analysis.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198556 91177308-0d34-0410-b5e6-96231b3b80d8
instructions. I needed this for a quick experiment I was making, and
while I've no idea if that will ever get committed, I didn't want to
throw away the pattern match code and for anyone else to have to write
it again. I've added unittests to make sure this works correctly.
In fun news, this also uncovered the IRBuilder bug. Doh!
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198541 91177308-0d34-0410-b5e6-96231b3b80d8
failed to correctly propagate the NUW and NSW flags to the constant
folder for two instructions. I've added a unittest to cover flag
propagation for the rest of the instructions and constant expressions.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198538 91177308-0d34-0410-b5e6-96231b3b80d8
basic block to hold instructions, and managing all of their lifetimes in
a fixture. This makes it easy to sink the expectations into the test
cases themselves which also makes things a bit more explicit and clearer
IMO.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198532 91177308-0d34-0410-b5e6-96231b3b80d8
__builtin_returnaddress requires that the value passed into is be a constant.
However, at -O0 even a constant expression may not be converted to a constant.
Emit an error message intead of crashing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198531 91177308-0d34-0410-b5e6-96231b3b80d8
All other uses of this macro in LLVM/clang have been moved to the function
definition so follow suite (and the usage advice) here too for consistency.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198516 91177308-0d34-0410-b5e6-96231b3b80d8
This commit was the source of crasher PR18384:
While deleting: label %for.cond127
An asserting value handle still pointed to this value!
UNREACHABLE executed at llvm/lib/IR/Value.cpp:671!
Reverting to get the builders green, feel free to re-land after fixing up.
(Renato has a handy isolated repro if you need it.)
This reverts commit r198478.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198503 91177308-0d34-0410-b5e6-96231b3b80d8
getSCEV for an ashr instruction creates an intermediate zext
expression when it truncates its operand.
The operand is initially inside the loop, so the narrow zext
expression has a non-loop-invariant loop disposition.
LoopSimplify then runs on an outer loop, hoists the ashr operand, and
properly invalidate the SCEVs that are mapped to value.
The SCEV expression for the ashr is now an AddRec with the hoisted
value as the now loop-invariant start value.
The LoopDisposition of this wide value was properly invalidated during
LoopSimplify.
However, if we later get the ashr SCEV again, we again try to create
the intermediate zext expression. We get the same SCEV that we did
earlier, and it is still cached because it was never mapped to a
Value. When we try to create a new AddRec we abort because we're using
the old non-loop-invariant LoopDisposition.
I don't have a solution for this other than to clear LoopDisposition
when LoopSimplify hoists things.
I think the long-term strategy should be to perform LoopSimplify on
all loops before computing SCEV and before running any loop opts on
individual loops. It's possible we may want to rerun LoopSimplify on
individual loops, but it should rarely do anything, so rarely require
invalidating SCEV.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198478 91177308-0d34-0410-b5e6-96231b3b80d8
