We can replace "scalar" FP-bitwise-logic with other forms of bitwise-logic instructions.
Scalar SSE/AVX FP-logic instructions only exist in your imagination and/or the bowels of
compilers, but logically equivalent int, float, and double variants of bitwise-logic
instructions are reality in x86, and the float variant may be a shorter instruction
depending on which flavor (SSE or AVX) of vector ISA you have...so just prefer float all
the time.
This is a preliminary step towards solving PR6137:
https://llvm.org/bugs/show_bug.cgi?id=6137
Differential Revision:
https://reviews.llvm.org/D26712
llvm-svn: 287122
-Don't print the 'x' suffix for the 128-bit reg/mem VEX encoded instructions in Intel syntax. This is consistent with the EVEX versions.
-Don't print the 'y' suffix for the 256-bit reg/reg VEX encoded instructions in Intel or AT&T syntax. This is consistent with the EVEX versions.
-Allow the 'x' and 'y' suffixes to be used for the reg/mem forms when we're assembling using Intel syntax.
-Allow the 'x' and 'y' suffixes on the reg/reg EVEX encoded instructions in Intel or AT&T syntax. This is consistent with what VEX was already allowing.
This should fix at least some of PR28850.
llvm-svn: 286787
This removes a couple tablegen classes that become unused after this change. Another class gained an additional parameter to allow PMADDUBSW to specify a different result type from its input type.
llvm-svn: 285515
MOVSD/MOVSS take a 128-bit register and a FR32/FR64 register input, the commutation code wasn't taking this into account leading to verification errors.
This patch inserts a vreg copy mi to ensure that the registers are correct.
Fix for PR30607
Differential Revision: https://reviews.llvm.org/D25280
llvm-svn: 283539
I don't know for sure that we truly needs this, but its the only vector load that isn't rematerializable. Making it consistent allows it to not be a special case in the td files.
llvm-svn: 283083
Instead of selecting between MOVSD/MOVSS and BLENDPD/BLENDPS at shuffle lowering by subtarget this will help us select the instruction based on actual commutation requirements.
We could possibly add BLENDPD/BLENDPS -> MOVSD/MOVSS commutation and MOVSD/MOVSS memory folding using a similar approach if it proves useful
I avoided adding AVX512 handling as I'm not sure when we should be making use of VBLENDPD/VBLENDPS on EVEX targets
llvm-svn: 283037
We can't use Jcc to leave a Win64 function in general, because that
confuses the unwinder. However, for "leaf" functions, that is, functions
where the return address is always on top of the stack and which don't
have unwind info, it's OK.
Differential Revision: https://reviews.llvm.org/D24836
llvm-svn: 282920
This adds new pseudo instructions that can be selected during register allocation to represent loads and stores of XMM/YMM registers when AVX512F is available, but VLX isn't. They will be converted to VEX encoded moves if the register turns out to be XMM0-15/YMM0-15. Otherwise either an EVEX VEXTRACT(store) or VBROADCAST(load) will be used.
Fixes one of the cases from PR29112.
llvm-svn: 282690
VPTERNLOG is a ternary instruction with an immediate specifying the logical operation to perform. For each bit position in the 3 source vectors the bit from each source is concatenated together and the resulting 3-bit value is used to select a bit in the immediate. This bit value is written to the result vector.
We can commute this by swapping operands and modifying the immediate. To modify the immediate we need to swap two pairs of bits. The pairs correspond to the locations in the immediate where the commuted operands bits have opposite values and the uncommuted operand has the same value. Bits 0 and 7 will never be swapped since the relevant bits from all sources are the same value.
This refactors and reuses parts of the FMA3 commuting code which is also a three operand instruction.
llvm-svn: 282132
r280832 added 32-bit support for emitting conditional tail-calls, but
dropped imp-used parameter registers. This went unnoticed until
r281113, which added 64-bit support, as this is only exposed with
parameter passing via registers.
Don't drop the imp-used parameters.
llvm-svn: 281223
Now that MachineBasicBlock::reverse_instr_iterator knows when it's at
the end (since r281168 and r281170), implement
MachineBasicBlock::reverse_iterator directly on top of an
ilist::reverse_iterator by adding an IsReverse template parameter to
MachineInstrBundleIterator. This replaces another hard-to-reason-about
use of std::reverse_iterator on list iterators, matching the changes for
ilist::reverse_iterator from r280032 (see the "out of scope" section at
the end of that commit message). MachineBasicBlock::reverse_iterator
now has a handle to the current node and has obvious invalidation
semantics.
r280032 has a more detailed explanation of how list-style reverse
iterators (invalidated when the pointed-at node is deleted) are
different from vector-style reverse iterators like std::reverse_iterator
(invalidated on every operation). A great motivating example is this
commit's changes to lib/CodeGen/DeadMachineInstructionElim.cpp.
Note: If your out-of-tree backend deletes instructions while iterating
on a MachineBasicBlock::reverse_iterator or converts between
MachineBasicBlock::iterator and MachineBasicBlock::reverse_iterator,
you'll need to update your code in similar ways to r280032. The
following table might help:
[Old] ==> [New]
delete &*RI, RE = end() delete &*RI++
RI->erase(), RE = end() RI++->erase()
reverse_iterator(I) std::prev(I).getReverse()
reverse_iterator(I) ++I.getReverse()
--reverse_iterator(I) I.getReverse()
reverse_iterator(std::next(I)) I.getReverse()
RI.base() std::prev(RI).getReverse()
RI.base() ++RI.getReverse()
--RI.base() RI.getReverse()
std::next(RI).base() RI.getReverse()
(For more details, have a look at r280032.)
llvm-svn: 281172
Summary:
An IR load can be invariant, dereferenceable, neither, or both. But
currently, MI's notion of invariance is IR-invariant &&
IR-dereferenceable.
This patch splits up the notions of invariance and dereferenceability at
the MI level. It's NFC, so adds some probably-unnecessary
"is-dereferenceable" checks, which we can remove later if desired.
Reviewers: chandlerc, tstellarAMD
Subscribers: jholewinski, arsenm, nemanjai, llvm-commits
Differential Revision: https://reviews.llvm.org/D23371
llvm-svn: 281151
Summary:
I want to separate out the notions of invariance and dereferenceability
at the MI level, so that they correspond to the equivalent concepts at
the IR level. (Currently an MI load is MI-invariant iff it's
IR-invariant and IR-dereferenceable.)
First step is renaming this function.
Reviewers: chandlerc
Subscribers: MatzeB, jfb, llvm-commits
Differential Revision: https://reviews.llvm.org/D23370
llvm-svn: 281125
This extends the optimization in r280832 to also work for 64-bit. The only
quirk is that we can't do this for 64-bit Windows (yet).
Differential Revision: https://reviews.llvm.org/D24423
llvm-svn: 281113
The REX prefix should be used on indirect jmps, but not direct ones.
For direct jumps, the unwinder looks at the offset to determine if
it's inside the current function.
Differential Revision: https://reviews.llvm.org/D24359
llvm-svn: 281003
When branching to a block that immediately tail calls, it is possible to fold
the call directly into the branch if the call is direct and there is no stack
adjustment, saving one byte.
Example:
define void @f(i32 %x, i32 %y) {
entry:
%p = icmp eq i32 %x, %y
br i1 %p, label %bb1, label %bb2
bb1:
tail call void @foo()
ret void
bb2:
tail call void @bar()
ret void
}
before:
f:
movl 4(%esp), %eax
cmpl 8(%esp), %eax
jne .LBB0_2
jmp foo
.LBB0_2:
jmp bar
after:
f:
movl 4(%esp), %eax
cmpl 8(%esp), %eax
jne bar
.LBB0_1:
jmp foo
I don't expect any significant size savings from this (on a Clang bootstrap I
saw 288 bytes), but it does make the code a little tighter.
This patch only does 32-bit, but 64-bit would work similarly.
Differential Revision: https://reviews.llvm.org/D24108
llvm-svn: 280832
The code is now written in terms of source and dest classes with feature checks inside each type of copy instead of having separate functions for each feature set.
llvm-svn: 280673
Previously we were extending to copying the whole ZMM register. The register allocator shouldn't use XMM16-31 or YMM16-31 in this configuration as the instructions to spill them aren't available.
llvm-svn: 280648
The only way to select them was in AVX512 mode because EVEX VMOVSS/SD was below them and the patterns weren't qualified properly for AVX only. So if you happened to have an aligned FR32/FR64 load in AVX512 you could get a VEX encoded VMOVAPS/VMOVAPD.
I tried to search back through history and it seems like these instructions were probably unselectable for at least 5 years, at least to the time the VEX versions were added. But I can't prove they ever were.
llvm-svn: 280644
According to spec cvtdq2pd and cvtps2pd instructions don't require memory operand to be aligned
to 16 bytes. This patch removes this requirement from the memory folding table.
Differential Revision: https://reviews.llvm.org/D23919
llvm-svn: 280402