Currently, the machine combiner can proceed matching when -ffast-math is on.
It should also match when only -ffp-contract=fast is specified as was the
case before when DAGCombiner was doing the job.
Patch by: Abderrazek Zaafrani <a.zaafrani@samsung.com>.
Differential Revision: https://reviews.llvm.org/D24366
llvm-svn: 281649
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
This recommit contains fixes for a nasty bug related to fast-isel fallback - because
fast-isel doesn't know about this optimization, if it runs and emits references to
a string that we inline (because fast-isel fell back to SDAG) we will end up
with an inlined string and also an out-of-line string, and we won't emit the
out-of-line string, causing backend failures.
llvm-svn: 281604
Summary:
It was previously not possible for tools to use solely the stackmap
information emitted to reconstruct the return addresses of callsites in
the map, which is necessary to use the information to walk a stack. This
patch adds per-function callsite counts when emitting the stackmap
section in order to resolve the problem. Note that this slightly alters
the stackmap format, so external tools parsing these maps will need to
be updated.
**Problem Details:**
Records only store their offset from the beginning of the function they
belong to. While these records and the functions are output in program
order, it is not possible to determine where the end of one function's
records are without the callsite count when processing the records to
compute return addresses.
Patch by Kavon Farvardin!
Reviewers: atrick, ributzka, sanjoy
Subscribers: nemanjai
Differential Revision: https://reviews.llvm.org/D23487
llvm-svn: 281532
Until AVX512DQ we only support i64/vXi64 sitofp conversion as scalars.
This patch sees if the sign bit extends far enough that we can truncate to a i32 type and then perform sitofp without loss of precision.
Differential Revision: https://reviews.llvm.org/D24345
llvm-svn: 281502
This addresses a TODO to handle operations besides and. This
also starts eliminating no-op operations with a constant that
can emerge later.
llvm-svn: 281488
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
llvm-svn: 281484
This patch corresponds to review:
https://reviews.llvm.org/D24021
In the initial implementation of this instruction, I forgot to account for
variable indices. This patch fixes PR30189 and should probably be merged into
3.9.1 (I'll open a bug according to the new instructions).
llvm-svn: 281479
Summary: When expanding mul in type legalization make sure the type for shift amount can actually fit the value. This fixes PR30354 https://llvm.org/bugs/show_bug.cgi?id=30354.
Reviewers: hfinkel, majnemer, RKSimon
Subscribers: RKSimon, llvm-commits
Differential Revision: https://reviews.llvm.org/D24478
llvm-svn: 281403
This allows us to, in some cases, create a vector_shuffle out of a build_vector, when
the inputs to the build are extract_elements from two different vectors, at least one
of which is wider than the output. (E.g. a <8 x i16> being constructed out of
elements from a <16 x i16> and a <8 x i16>).
Differential Revision: https://reviews.llvm.org/D24491
llvm-svn: 281402
Cleanup/change the code that checks for possible tailcall conventions to
look the same as the one in the X86 target. This makes the distinction
between calling conventions that can guarnatee tailcalls and the ones
that may tailcall more obvious.
- Add Swift to the mayTailCall list
- PreserveMost seemed to be incorrectly part of the guarnteed tail call
list, move it to the mayTailCall list.
llvm-svn: 281376
To avoid assertion, we must ensure that the inner shift constant is within range before calling ConstantSDNode::getZExtValue(). We already know that the outer shift constant is in range.
Followup to D23007
llvm-svn: 281362
Before, only Thumb functions were marked as ".code 16". These
".code x" directives are effective until the next directive of its
kind is encountered. Therefore, in code with interleaved ARM and
Thumb functions, it was possible to declare a function as ARM and
end up with a Thumb function after assembly. A test has been added.
An existing test has also been fixed to take this change into
account.
Reviewers: aschwaighofer, t.p.northover, jmolloy, rengolin
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: https://reviews.llvm.org/D24337
llvm-svn: 281324
For the common pattern (CMPZ (AND x, #bitmask), #0), we can do some more efficient instruction selection if the bitmask is one consecutive sequence of set bits (32 - clz(bm) - ctz(bm) == popcount(bm)).
1) If the bitmask touches the LSB, then we can remove all the upper bits and set the flags by doing one LSLS.
2) If the bitmask touches the MSB, then we can remove all the lower bits and set the flags with one LSRS.
3) If the bitmask has popcount == 1 (only one set bit), we can shift that bit into the sign bit with one LSLS and change the condition query from NE/EQ to MI/PL (we could also implement this by shifting into the carry bit and branching on BCC/BCS).
4) Otherwise, we can emit a sequence of LSLS+LSRS to remove the upper and lower zero bits of the mask.
1-3 require only one 16-bit instruction and can elide the CMP. 4 requires two 16-bit instructions but can elide the CMP and doesn't require materializing a complex immediate, so is also a win.
llvm-svn: 281323
If a constant is unamed_addr and is only used within one function, we can save
on the code size and runtime cost of an indirection by changing the global's storage
to inside the constant pool. For example, instead of:
ldr r0, .CPI0
bl printf
bx lr
.CPI0: &format_string
format_string: .asciz "hello, world!\n"
We can emit:
adr r0, .CPI0
bl printf
bx lr
.CPI0: .asciz "hello, world!\n"
This can cause significant code size savings when many small strings are used in one
function (4 bytes per string).
llvm-svn: 281314
descriptions now tag add instructions, and the Hexagon backend is using this to
identify loop induction statements.
Patch by Sam Parker and Sjoerd Meijer.
Differential Revision: https://reviews.llvm.org/D23601
llvm-svn: 281304
Optimized (truncate (assertzext x) to i1) and anyext i1 to i8/16/32.
Optimization of this patterns is a one more step towards i1 optimization on AVX-512.
Differential Revision: https://reviews.llvm.org/D24456
llvm-svn: 281302
We currently return 4 for stackmaps and patchpoints, which is very optimistic
and can in rare cases cause the branch relaxation pass to fail to relax certain
branches.
This patch causes getInstSizeInBytes to return a pessimistic estimate of the
size as the number of bytes requested in the stackmap/patchpoint. In the future,
we could provide a more accurate estimate by sharing some of the logic in
AArch64::LowerSTACKMAP/PATCHPOINT.
Fixes part of https://llvm.org/bugs/show_bug.cgi?id=28750
Differential Revision: https://reviews.llvm.org/D24073
llvm-svn: 281301
This patch reverses the edge from DIGlobalVariable to GlobalVariable.
This will allow us to more easily preserve debug info metadata when
manipulating global variables.
Fixes PR30362. A program for upgrading test cases is attached to that
bug.
Differential Revision: http://reviews.llvm.org/D20147
llvm-svn: 281284
That confuses e.g. machine basic block placement, which then doesn't
realize that control can fall through a block that ends with a conditional
tail call. Instead, isBranch=1 should be set.
Also, mark EFLAGS as used by these instructions.
llvm-svn: 281281
Evandro Menezes