Some debuggers/profilers use this metadata to determine which function a
given instruction is in; without it they get can confused by local labels
(if you haven't stripped those). On the other hand, some tools are still
confused even with this metadata. e.g. this fixes `gdb`, but not `perf`.
Currently only implemented for ELF.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
The REP_RET workaround is only needed on old AMD cpus, and the labels clutter
up the symbol table and confuse debugging/profiling tools, so use EQU to
create SHN_ABS symbols instead of creating local labels. Furthermore, skip
the workaround completely in functions that definitely won't run on such cpus.
Note that EQU is just creating a local label when using nasm instead of yasm.
This is probably a bug, but at least it doesn't break anything.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
When allocating stack space with a larger alignment than the known stack
alignment a temporary register is used for storing the stack pointer.
Ensure that this isn't one of the registers used for passing arguments.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
* Correctly handle FMA instructions with memory operands.
* Print a warning if FMA instructions are used without the correct cpuflag.
* Simplify the instantiation code.
* Clarify documentation.
Only the last operand in FMA3 instructions can be a memory operand. When
converting FMA4 instructions to FMA3 instructions we can utilize the fact
that multiply is a commutative operation and reorder operands if necessary
to ensure that a memory operand is used only as the last operand.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Some debuggers/profilers use this metadata to determine which function a
given instruction is in; without it they get can confused by local labels
(if you haven't stripped those). On the other hand, some tools are still
confused even with this metadata. e.g. this fixes `gdb`, but not `perf`.
Currently only implemented for ELF.
The REP_RET workaround is only needed on old AMD cpus, and the labels clutter
up the symbol table and confuse debugging/profiling tools, so use EQU to
create SHN_ABS symbols instead of creating local labels. Furthermore, skip
the workaround completely in functions that definitely won't run on such cpus.
Note that EQU is just creating a local label when using nasm instead of yasm.
This is probably a bug, but at least it doesn't break anything.
When allocating stack space with a larger alignment than the known stack
alignment a temporary register is used for storing the stack pointer.
Ensure that this isn't one of the registers used for passing arguments.
* Correctly handle FMA instructions with memory operands.
* Print a warning if FMA instructions are used without the correct cpuflag.
* Simplify the instantiation code.
* Clarify documentation.
Only the last operand in FMA3 instructions can be a memory operand. When
converting FMA4 instructions to FMA3 instructions we can utilize the fact
that multiply is a commutative operation and reorder operands if necessary
to ensure that a memory operand is used only as the last operand.
The .text section is already 16-byte aligned by default on all supported
platforms so `SECTION_TEXT` isn't any different from `SECTION .text`.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Change ALLOC_STACK to always align the stack before allocating stack space for
consistency. Previously alignment would occur either before or after allocating
stack space depending on whether manual alignment was required or not.
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Emulation requires a temporary register if arguments 1 and 4 are the same; this
doesn't obey the semantics of the original instruction, so we can't emulate
that in x86inc.
Also add pmacsdql emulation.
Signed-off-by: Henrik Gramner <henrik@gramner.com>
Signed-off-by: Anton Khirnov <anton@khirnov.net>
Change ALLOC_STACK to always align the stack before allocating stack space for
consistency. Previously alignment would occur either before or after allocating
stack space depending on whether manual alignment was required or not.
Only two functions that use xop multiply-accumulate instructions where the
first operand is the same as the fourth actually took advantage of the macros.
This further reduces differences with x264's x86inc.
Reviewed-by: Ronald S. Bultje <rsbultje@gmail.com>
Signed-off-by: James Almer <jamrial@gmail.com>
The bug was fixed in 1.3.0, so only perform the workaround in earlier versions.
Reviewed-by: "Ronald S. Bultje" <rsbultje@gmail.com>
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
Silences warning(s) like:
libavcodec/x86/fft.asm:93: warning: section flags ignored on
section redeclaration
The cause of this warning is that because `struc` and `endstruc`
attempts to revert to the previous section state [1].
The section state is stored in the macro __SECT__, defined by
x86inc.asm to be `.note.GNU-stack ...`, through the `SECTION`
directive [2].
Thus, the `.note.GNU-stack` section is defined twice
(once in x86inc.asm, once during `endstruc`), causing the warning.
That is the first part of the commit: using the primitive `[section]` format
for .note.GNU-stack etc., which does not update `__SECT__` [2].
That fixes only half of the problem. Even without any `SECTION` directives,
`__SECT__` is predefined as `.text`, which conflicting with the later
`SECTION_TEXT` (which expands to `.text align=16`).
[1]: http://www.nasm.us/doc/nasmdoc6.html#section-6.4
[2]: http://www.nasm.us/doc/nasmdoc6.html#section-6.3
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>
This commit silences warning(s) like:
libavcodec/x86/fft.asm:93: warning: section flags ignored on section
redeclaration
The cause of this warning is that because `struc` and `endstruc` attempts to
revert to the previous section state [1]. The section state is stored in the
macro __SECT__, defined by x86inc.asm to be `.note.GNU-stack ...`, through the
`SECTION` directive [2]. Thus, the `.note.GNU-stack` section is defined twice
(once in x86inc.asm, once during `endstruc`), causing the warning.
That is the first part of the commit: using the primitive `[section]` format
for .note.GNU-stack etc., which does not update `__SECT__` [2].
That fixes only half of the problem. Even without any `SECTION` directives,
`__SECT__` is predefined as `.text`, which conflicting with the later
`SECTION_TEXT` (which expands to `.text align=16`).
[1]: http://www.nasm.us/doc/nasmdoc6.html#section-6.4
[2]: http://www.nasm.us/doc/nasmdoc6.html#section-6.3
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
SSE2 instructions that are XMM-implementations of pre-existing MMX/MMX2
instructions did not issue warnings when used in SSE functions. Handle
it by also checking the register type when such instructions are used.
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This mimicks what is done for the other instruction sets.
Tested-by: James Almer <jamrial@gmail.com>
Tested-by: Mickaël Raulet <mraulet@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
We need the emulation to support the cases where the first
argument is the same as the fourth. To achieve this a fifth
argument working as a temporary may be needed.
Emulation that doesn't obey the original instruction semantics
can't be in x86inc.
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Support the cases where the first and last operand of
the XOP instruction are the same.
Also add vpmacsdql emulation.
Signed-off-by: James Almer <jamrial@gmail.com>
Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
This is so we can sync to x264's version of FMA4 support.
This partialy reverts commit 79687079a9.
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>
Geza Lore
Henrik Gramner
Rodger Combs
Christophe Gisquet
Anton Mitrofanov
James Almer
Timothy Gu
James Darnley
Loren Merritt
Diego Biurrun
Jason Garrett-Glaser
Derek Buitenhuis