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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@282241 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281715 91177308-0d34-0410-b5e6-96231b3b80d8
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.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281604 91177308-0d34-0410-b5e6-96231b3b80d8
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).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281484 91177308-0d34-0410-b5e6-96231b3b80d8
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
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281324 91177308-0d34-0410-b5e6-96231b3b80d8
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).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281314 91177308-0d34-0410-b5e6-96231b3b80d8
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).
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281213 91177308-0d34-0410-b5e6-96231b3b80d8
And associated commits, as they broke the Thumb bots.
This reverts commit r280935.
This reverts commit r280891.
This reverts commit r280888.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@280967 91177308-0d34-0410-b5e6-96231b3b80d8
This is a mechanical change of comments in switches like fallthrough,
fall-through, or fall-thru to use the LLVM_FALLTHROUGH macro instead.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278902 91177308-0d34-0410-b5e6-96231b3b80d8
This patch adds support for some new relocation models to the ARM
backend:
* Read-only position independence (ROPI): Code and read-only data is accessed
PC-relative. The offsets between all code and RO data sections are known at
static link time. This does not affect read-write data.
* Read-write position independence (RWPI): Read-write data is accessed relative
to the static base register (r9). The offsets between all writeable data
sections are known at static link time. This does not affect read-only data.
These two modes are independent (they specify how different objects
should be addressed), so they can be used individually or together. They
are otherwise the same as the "static" relocation model, and are not
compatible with SysV-style PIC using a global offset table.
These modes are normally used by bare-metal systems or systems with
small real-time operating systems. They are designed to avoid the need
for a dynamic linker, the only initialisation required is setting r9 to
an appropriate value for RWPI code.
I have only added support to SelectionDAG, not FastISel, because
FastISel is currently disabled for bare-metal targets where these modes
would be used.
Differential Revision: https://reviews.llvm.org/D23195
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@278015 91177308-0d34-0410-b5e6-96231b3b80d8
Windows on ARM uses a pure thumb-2 environment. This means that it can select a
high register when doing a __builtin_longjmp. We would use a tLDRi which would
truncate the register to a low register. Use a t2LDRi12 to get the full
register file access. Tweak the code to just load into PC, as that is an
interworking branch on all supported cores anyways.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@274815 91177308-0d34-0410-b5e6-96231b3b80d8
The R_ARM_PLT32 relocation is deprecated and is not produced by MC.
This means that the code being deleted is dead from the .o point of
view and was making the .s more confusing.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@272909 91177308-0d34-0410-b5e6-96231b3b80d8
TLS access requires an offset from the TLS index. The index itself is the
section-relative distance of the symbol. For ARM, the relevant relocation
(IMAGE_REL_ARM_SECREL) is applied as a constant. This means that the value may
not be an immediate and must be lowered into a constant pool. This offset will
not be base relocated. We were previously emitting the actual address of the
symbol which would be base relocated and would therefore be the vaue offset by
the ImageBase + TLS Offset.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@271974 91177308-0d34-0410-b5e6-96231b3b80d8
clang-tidy's performance-unnecessary-copy-initialization with some manual
fixes. No functional changes intended.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@270988 91177308-0d34-0410-b5e6-96231b3b80d8
Since r207518 they are printed exactly like non-hidden stubs on x86 and
since r207517 on ARM.
This means we can use a single set for all stubs in those platforms.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269776 91177308-0d34-0410-b5e6-96231b3b80d8
It seems that cl will emit the export directives for Windows ARM targets. The
fact that it did this had originally been missed and this functionality was
never implemented. This makes it possible to rely solely on the source code for
indicating what the exported interfaces are and brings us more compatibility
with cl.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@269574 91177308-0d34-0410-b5e6-96231b3b80d8
The initial change was insufficiently complete for always getting the semantics
of __builtin_longjmp correct. The builtin is translated into a
`tInt_eh_sjlj_longjmp` DAG node. This node set R7 as clobbered. However, the
code would then follow up with a clobber of R11. I had failed to notice the
imp-def,kill on R7 in the isel. Unfortunately, it seems that it is not possible
to conditionalise the Defs list via an !if. Instead, construct a new parallel
WIN node and prefer that when targeting windows. This ensures that we now both
correctly model the __builtin_longjmp as well as construct the frame in a more
ABI conformant manner.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@263123 91177308-0d34-0410-b5e6-96231b3b80d8
WoA uses r11 as the FP even though it is a pure thumb-2 environment in contrast
to AAPCS which states r7. This adjusts __builtin_longjmp to not clobber r7 and
to properly restore the frame pointer on execution.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@263118 91177308-0d34-0410-b5e6-96231b3b80d8
This patch was originally committed as r257885, but was reverted due to windows
failures. The cause of these failures has been fixed under r258677, hence
re-committing the original patch.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@258683 91177308-0d34-0410-b5e6-96231b3b80d8
# The first commit's message is:
Revert "[ARM] Add DSP build attribute and extension targeting"
This reverts commit b11cc50c0b4a7c8cdb628abc50b7dc226ff583dc.
# This is the 2nd commit message:
Revert "[ARM] Add new system registers to ARMv8-M Baseline/Mainline"
This reverts commit 837d08454e3e5beb8581951ac26b22fa07df3cd5.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@257916 91177308-0d34-0410-b5e6-96231b3b80d8
EABI attributes should only be emitted on EABI targets. This prevents the
emission of the optimization goals EABI attribute on Windows ARM.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255448 91177308-0d34-0410-b5e6-96231b3b80d8
This reverts commit r254201 and r254202, as it broke test-suite,
self-hosting and sanitizer tests on ARM buildbots.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254234 91177308-0d34-0410-b5e6-96231b3b80d8
Summary:
Since this build attribute corresponds to a whole module, and
different functions in a module may differ in the optimizations
enabled for them, this attribute is emitted after all functions,
and only in the case that the optimization goals for all
functions match.
Reviewers: logan, hans
Subscribers: aemerson, rengolin, llvm-commits
Differential Revision: http://reviews.llvm.org/D14934
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@254201 91177308-0d34-0410-b5e6-96231b3b80d8
In PIC mode we were previously computing global variable addresses (or GOT
entry addresses) by adding the PC, the PC-relative GOT displacement and
the GOT-relative symbol/GOT entry displacement. Because the latter two
displacements are fixed, we ended up performing one more addition than
necessary.
This change causes us to compute addresses using a single PC-relative
displacement, resulting in a shorter code sequence. This reduces code size
by about 4% in a recent build of Chromium for Android.
As a result of this change we no longer need to compute the GOT base address
in the ARM backend, which allows us to remove the Global Base Reg pass and
SDAG lowering for the GOT.
We also now no longer use the GOT when addressing a symbol which is known
to be defined in the same linkage unit. Specifically, the symbol must have
either hidden visibility or a strong definition in the current module in
order to not use the the GOT.
This is a change from the previous behaviour where we would use the GOT to
address externally visible symbols defined in the same module. I think the
only cases where this could matter are cases involving symbol interposition,
but we don't really support that well anyway.
Differential Revision: http://reviews.llvm.org/D13650
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@251322 91177308-0d34-0410-b5e6-96231b3b80d8
Currently, the availability of DSP instructions (ACLE 6.4.7) is handled in a
hand-rolled tricky condition block in tools/clang/lib/Basic/Targets.cpp, with
a FIXME: attached.
This patch changes the handling of +t2dsp to be in line with other
architecture extensions.
Following a revert of r248152 and new review comments, this patch also includes
renaming FeatureDSPThumb2 -> FeatureDSP, hasThumb2DSP() -> hasDSP(), etc.
The spelling of "t2dsp" is preserved, pending a further investigation of its
possible external usage.
Differential Revision: http://reviews.llvm.org/D12937
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@248519 91177308-0d34-0410-b5e6-96231b3b80d8
