This patch corresponds to review:
https://reviews.llvm.org/D21135
This patch exploits the following instructions:
mtvsrws
lxvwsx
mtvsrdd
mfvsrld
In order to improve some build_vector and extractelement patterns.
llvm-svn: 282246
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.
It also contains fixes for emitting .text relocations which made the sanitizer
bots unhappy.
llvm-svn: 282241
According to MSDN (see the PR), functions which don't touch any callee-saved
registers (including %rsp) don't need any unwind info.
This patch makes LLVM not emit unwind info for such functions, to save
binary size.
Differential Revision: https://reviews.llvm.org/D24748
llvm-svn: 282185
Atomic comparison instructions use the sub-word load instruction on
Power8 and up but the value is not sign extended prior to the signed word
compare instruction. This patch adds that sign extension.
llvm-svn: 282182
This patch corresponds to review:
https://reviews.llvm.org/D19825
The new lxvx/stxvx instructions do not require the swaps to line the elements
up correctly. In order to select them over the lxvd2x/lxvw4x instructions which
require swaps, the patterns for the old instruction have a predicate that
ensures they won't be selected on Power9 and newer CPUs.
llvm-svn: 282143
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
We still don't really have an equivalent of "AssertXExt" in DAG, so we don't
exploit the guarantees on the receiving side yet, but this should produce
conservatively correct code on iOS ABIs.
llvm-svn: 282069
The postRA scheduler performs alias analysis to determine if stores and loads
can moved past each other. When a function has more arguments than argument
registers for the calling convention used, excess arguments are spilled onto the
stack. LLVM by default assumes that argument slots are immutable, unless the
function contains a tail call. Without the knowledge of that a function contains
a tail call site, stores and loads to fixed stack slots may be re-ordered
causing the out-going arguments to clobber the incoming arguments before the
incoming arguments are supposed to be dead.
Reviewers: vkalintiris
Differential Review: https://reviews.llvm.org/D24077
llvm-svn: 282063
Summary: In getArgumentAlignment check if the ImmutableCallSite pointer CS is non-null before dereferencing. If CS is 0x0 fall back to the ABI type alignment else compute the alignment as before.
Reviewers: eliben, jpienaar
Subscribers: jlebar, vchuravy, cfe-commits, jholewinski
Differential Revision: https://reviews.llvm.org/D9168
llvm-svn: 282045
Previously, such section would be marked as SHT_PROGBITS which
makes it impossible to use an initialized C variable declaration
to emit an (allocated) ELF note. The new behavior is also consistent
with ELF assembly parser.
Differential Revision: https://reviews.llvm.org/D24692
llvm-svn: 282010
This reverts commit b7d42b0048f65346e9fa37fb65defeea7ce8c337 per request by
Eric Christopher <echristo@gmail.com> (v. http://bit.ly/2cmz6kW).
llvm-svn: 282000
This reverts commit ad8ca1528242e2a4cb363e3779309e70eb7a430e per request by
Eric Christopher <echristo@gmail.com> (v. http://bit.ly/2cmz6kW).
llvm-svn: 281999
This should match the existing behaviour for passing complicated struct and
array types, in particular HFAs come through like that from Clang.
For C & C++ we still need to somehow support all the weird ABI flags, or at
least those that are present in the IR (signext, byval, ...), and stack-based
parameter passing.
llvm-svn: 281977
It is legal to merge instructions with different undef flags; However we
must drop the undef flag from the merged instruction if it isn't present
everywhere.
This fixes http://llvm.org/PR30199
llvm-svn: 281957
Machine programs need a definition of each vreg before reaching a use
(the definition may come from an IMPLICIT_DEF instruction). This class
of errors is not detected by the MachineVerifier because of efficiency
concerns. LiveRangeCalc used to report these problems, make it do that
again (followup to r279625).
Also use report_fatal_error() instead of llvm_unreachable() as the error
reporting is only present in asserts build anyway.
llvm-svn: 281914
ldm and stm instructions always require 4-byte alignment on the pointer, but we
weren't checking this before trying to reduce code-size by replacing a
post-indexed load/store with them. Unfortunately, we were also dropping this
incormation in DAG ISel too, but that's easy enough to fix.
llvm-svn: 281893
SUBREG_TO_REG is supposed to indicate that the super register has been zeroed, but we can't prove that if we don't know where it came from.
llvm-svn: 281885
This is a port of XRay to ARM 32-bit, without Thumb support yet. The XRay instrumentation support is moving up to AsmPrinter.
This is one of 3 commits to different repositories of XRay ARM port. The other 2 are:
https://reviews.llvm.org/D23932 (Clang test)
https://reviews.llvm.org/D23933 (compiler-rt)
Differential Revision: https://reviews.llvm.org/D23931
llvm-svn: 281878
With D24253 we can now use SelectionDAG::SignBitIsZero with vector operations.
This patch uses SelectionDAG::SignBitIsZero to recognise that a zero sign bit means that we can use a sitofp instead of a uitofp (which is not directly support on pre-AVX512 hardware).
While AVX512 does provide support for uitofp, the conversion to sitofp should not cause any regressions.
Differential Revision: https://reviews.llvm.org/D24343
llvm-svn: 281852
We were trying to avoid using a FrameIndex operand in non-pointer
operands in a convoluted way, and would break because of
using TargetFrameIndex. The TargetFrameIndex should only be used
in the case where it makes sense to fold it as part of the addressing
mode, otherwise it requires materialization like a normal constant.
This wasn't working reliably and failed in the added testcase, hitting
the assert when processing the frame index.
The TargetFrameIndex was coming from trying to produce an AssertZext
limiting the maximum stack size. I'm not sure this was correct to begin
with, because it is apparently possible to have a single workitem
dispatch that requires all 4G of private memory.
llvm-svn: 281824
This reduces the number of copies and reg_sequences
when using fp constant vectors. This significantly
reduces the code size in local-stack-alloc-bug.ll
llvm-svn: 281822
