there are clearly no stores between the load and the store. This fixes
this miscompile reported as PR7833.
This breaks the test/CodeGen/X86/narrow_op-2.ll optimization, which is
safe, but awkward to prove safe. Move it to X86's README.txt.
llvm-svn: 112861
add, and subtract operations with zero-extended or sign-extended vectors.
Update tests. Add auto-upgrade support for the old intrinsics.
llvm-svn: 112773
check more strict, breaking some cases not checked in the
testsuite, but also exposes some foldings not done before,
as this example:
movaps (%rdi), %xmm0
movaps (%rax), %xmm1
movaps %xmm0, %xmm2
movss %xmm1, %xmm2
shufps $36, %xmm2, %xmm0
now is generated as:
movaps (%rdi), %xmm0
movaps %xmm0, %xmm1
movlps (%rax), %xmm1
shufps $36, %xmm1, %xmm0
llvm-svn: 112753
int x(int t) {
if (t & 256)
return -26;
return 0;
}
We generate this:
tst.w r0, #256
mvn r0, #25
it eq
moveq r0, #0
while gcc generates this:
ands r0, r0, #256
it ne
mvnne r0, #25
bx lr
Scandalous really!
During ISel time, we can look for this particular pattern. One where we have a
"MOVCC" that uses the flag off of a CMPZ that itself is comparing an AND
instruction to 0. Something like this (greatly simplified):
%r0 = ISD::AND ...
ARMISD::CMPZ %r0, 0 @ sets [CPSR]
%r0 = ARMISD::MOVCC 0, -26 @ reads [CPSR]
All we have to do is convert the "ISD::AND" into an "ARM::ANDS" that sets [CPSR]
when it's zero. The zero value will all ready be in the %r0 register and we only
need to change it if the AND wasn't zero. Easy!
llvm-svn: 112664
kill flag.
This could cause duplicate kill flags when the same register was used twice in a
continuous sequence of STRs.
There is no small test case. <rdar://problem/8218046>
llvm-svn: 112534
operand is killed, add it to the expanded instruction as an implicit kill
operand instead of marking the individual subregs with kill flags. This
should work better in general and also handles the case for VST3 where one
of the subregs was not referenced in the expanded instruction and so was
not marked killed.
llvm-svn: 112494
optional modified register (instead of reg0). Along with r112461 it will make
sure that the optional define of CPSR is marked as "def" and will thus mark the
instructions using these classes (t2ANDS*) as setting the 's' flag.
llvm-svn: 112462
times. This patch causes llc and llvm-mc (which both default to
verbose-asm) to print out comments after a few common shuffle
instructions which indicates the shuffle mask, e.g.:
insertps $113, %xmm3, %xmm0 ## xmm0 = zero,xmm0[1,2],xmm3[1]
unpcklps %xmm1, %xmm0 ## xmm0 = xmm0[0],xmm1[0],xmm0[1],xmm1[1]
pshufd $1, %xmm1, %xmm1 ## xmm1 = xmm1[1,0,0,0]
This is carefully factored to keep the information extraction (of the
shuffle mask) separate from the printing logic. I plan to move the
extraction part out somewhere else at some point for other parts of
the x86 backend that want to introspect on the behavior of shuffles.
llvm-svn: 112387
when the top elements of a vector are undefined. This happens all
the time for X86-64 ABI stuff because only the low 2 elements of
a 4 element vector are defined. For example, on:
_Complex float f32(_Complex float A, _Complex float B) {
return A+B;
}
We used to produce (with SSE2, SSE4.1+ uses insertps):
_f32: ## @f32
movdqa %xmm0, %xmm2
addss %xmm1, %xmm2
pshufd $16, %xmm2, %xmm2
pshufd $1, %xmm1, %xmm1
pshufd $1, %xmm0, %xmm0
addss %xmm1, %xmm0
pshufd $16, %xmm0, %xmm1
movdqa %xmm2, %xmm0
unpcklps %xmm1, %xmm0
ret
We now produce:
_f32: ## @f32
movdqa %xmm0, %xmm2
addss %xmm1, %xmm2
pshufd $1, %xmm1, %xmm1
pshufd $1, %xmm0, %xmm3
addss %xmm1, %xmm3
movaps %xmm2, %xmm0
unpcklps %xmm3, %xmm0
ret
This implements rdar://8368414
llvm-svn: 112378
Also teach this logic how to handle target specific shuffles if
needed, this is necessary while searching recursively for zeroed
scalar elements in vector shuffle operands.
llvm-svn: 112348
the special values that for ARM would be used with IB or DA modes. Fall
through and consider materializing a new base address is it would be
profitable.
llvm-svn: 112329
all the other LDM/STM instructions. This fixes asm printer crashes when
compiling with -O0. I've changed one of the NEON tests (vst3.ll) to run
with -O0 to check this in the future.
Prior to this change VLDM/VSTM used addressing mode #5, but not really.
The offset field was used to hold a count of the number of registers being
loaded or stored, and the AM5 opcode field was expanded to specify the IA
or DB mode, instead of the standard ADD/SUB specifier. Much of the backend
was not aware of these special cases. The crashes occured when rewriting
a frameindex caused the AM5 offset field to be changed so that it did not
have a valid submode. I don't know exactly what changed to expose this now.
Maybe we've never done much with -O0 and NEON. Regardless, there's no longer
any reason to keep a count of the VLDM/VSTM registers, so we can use
addressing mode #4 and clean things up in a lot of places.
llvm-svn: 112322
still having a significant effect. It shouldn't be now that the pre-RA
virtual base reg stuff is in. Assuming that's valididated by the nightly
testers, we can simplify a lot of the PEI frame index code.
llvm-svn: 112220
fix: add a flag to MapValue and friends which indicates whether
any module-level mappings are being made. In the common case of
inlining, no module-level mappings are needed, so MapValue doesn't
need to examine non-function-local metadata, which can be very
expensive in the case of a large module with really deep metadata
(e.g. a large C++ program compiled with -g).
This flag is a little awkward; perhaps eventually it can be moved
into the ClonedCodeInfo class.
llvm-svn: 112190
comparison with 0. These two pieces of code should give identical results:
rsbs r1, r1, 0
cmp r0, r1
mov r0, #0
it ls
mov r0, #1
and:
cmn r0, r1
mov r0, #0
it ls
mov r0, #1
However, the CMN gives the *opposite* result when r1 is 0. This is because the
carry flag is set in the CMP case but not in the CMN case. In short, the CMP
instruction doesn't perform a truncate of the (logical) NOT of 0 plus the value
of r0 and the carry bit (because the "carry bit" parameter to AddWithCarry is
defined as 1 in this case, the carry flag will always be set when r0 >= 0). The
CMN instruction doesn't perform a NOT of 0 so there is never a "carry" when this
AddWithCarry is performed (because the "carry bit" parameter to AddWithCarry is
defined as 0).
The AddWithCarry in the CMP case seems to be relying upon the identity:
~x + 1 = -x
However when x is 0 and unsigned, this doesn't hold:
x = 0
~x = 0xFFFF FFFF
~x + 1 = 0x1 0000 0000
(-x = 0) != (0x1 0000 0000 = ~x + 1)
Therefore, we should disable *all* versions of CMN, especially when comparing
against zero, until we can limit when the CMN instruction is used (when we know
that the RHS is not 0) or when we have a hardware fix for this.
(See the ARM docs for the "AddWithCarry" pseudo-code.)
This is related to <rdar://problem/7569620>.
llvm-svn: 112176
with the VST4 instructions. Until after register allocation, we want to
represent sets of adjacent registers by a single super-register. These
VST4 pseudo instructions have a single QQ or QQQQ source register operand.
They get expanded to the real VST4 instructions with 4 separate D register
operands. Once this conversion is complete, we'll be able to remove the
NEONPreAllocPass and avoid some fragile and hacky code elsewhere.
llvm-svn: 112108
comparison that would overflow.
- The other under/overflow cases can't actually happen because the immediates
which would trigger them are legal (so we don't enter this code), but
adjusted the style to make it clear the transform is always valid.
llvm-svn: 112053
Bruno Cardoso Lopes