Mercurial > pub > dyncall > dyncall
diff doc/manual/callconvs/callconv_sparc64.tex @ 328:276eb8c87aa0
- review and fixes, cleanup, amendments to calling convention appendix of manual
author | Tassilo Philipp |
---|---|
date | Fri, 22 Nov 2019 23:11:56 +0100 |
parents | dd1d0b0fd896 |
children | 4e6f63b7020e |
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--- a/doc/manual/callconvs/callconv_sparc64.tex Fri Nov 22 23:08:59 2019 +0100 +++ b/doc/manual/callconvs/callconv_sparc64.tex Fri Nov 22 23:11:56 2019 +0100 @@ -1,112 +1,115 @@ -%////////////////////////////////////////////////////////////////////////////// -% -% Copyright (c) 2012-2017 Daniel Adler <dadler@uni-goettingen.de>, -% Tassilo Philipp <tphilipp@potion-studios.com> -% -% Permission to use, copy, modify, and distribute this software for any -% purpose with or without fee is hereby granted, provided that the above -% copyright notice and this permission notice appear in all copies. -% -% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES -% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF -% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR -% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES -% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN -% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF -% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. -% -%////////////////////////////////////////////////////////////////////////////// - -\subsection{SPARC64 Calling Convention} - -\paragraph{Overview} - -The SPARC family of processors is based on the SPARC instruction set architecture, which comes in basically tree revisions, -V7, V8\cite{SPARCV8}\cite{SPARCSysV} and V9\cite{SPARCV9}\cite{SPARCV9SysV}. The former two are 32-bit (see previous chapter) whereas the latter refers to the 64-bit SPARC architecture. -SPARC uses big endian byte order, however, V9 supports also little endian byte order, but for data access only, not instruction access.\\ -\\ -There are two proposals, one from Sun and one from Hal, which disagree on how to handle some aspects of this calling convention.\\ - -\paragraph{\product{dyncall} support} - -\product{dyncall} fully supports the SPARC 64-bit instruction set (V9), for calls and callbacks. - -\subsubsection{SPARC (64-bit) Calling Convention} - -\begin{itemize} -\item 32 double precision floating point registers (d0,d2,d4,...,d62, usable as 16 quad precision ones q0,q4,q8,...g60, and also first half of them are usable as 32 single precision registers f0-f31) -\item 32 64-bit integer/pointer registers out of a bigger (vendor/model dependent) number that are accessible at a time (8 are global ones (g*), whereas the remaining 24 form a register window with 8 input (i*), 8 output (o*) and 8 local (l*) ones) -\item calling a function shifts the register window, the old output registers become the new input registers (old local and input ones are not accessible anymore) -\item stack and frame pointer are offset by a BIAS of 2047 (see official doc for reasons) -\end{itemize} - -\begin{table}[h] -\begin{tabular*}{0.95\textwidth}{lll} -Name & Alias & Brief description\\ -\hline -{\bf \%g0} & \%r0 & Read-only, hardwired to 0 \\ -{\bf \%g1-\%g7} & \%r1-\%r7 & Global \\ -{\bf \%o0-\%o3 and \%i0-\%i3} & \%r8-\%r11 and \%r24-\%r27 & Output and input argument registers, return value \\ -{\bf \%o4,\%o5 and \%i4,\%i5} & \%r12,\%r13 and \%r28,\%r29 & Output and input argument registers \\ -{\bf \%o6 and \%i6} & \%r14 and \%r30, \%sp and \%fp & Stack and frame pointer (NOTE, value is pointing to stack/frame minus a BIAS of 2047) \\ -{\bf \%o7 and \%i7} & \%r15 and \%r31 & Return address (caller writes to o7, callee uses i7) \\ -{\bf \%l0-\%l7} & \%r16-\%r23 & preserve \\ -{\bf \%d0,\%d2,\%d4,\%d6} & & Floating point arguments, return value \\ -{\bf \%d8,\%d10,...,\%d30} & & Floating point arguments \\ -{\bf \%d32,\%d36,...,\%d62} & & scratch (but, according do Hal, \%d16,...,\%d46 are preserved) \\ -\end{tabular*} -\caption{Register usage on sparc64 calling convention} -\end{table} - -\paragraph{Parameter passing} -\begin{itemize} -\item stack grows down -\item stack parameter order: right-to-left -\item caller cleans up the stack -\item stack frame is always aligned to 16 bytes -\item first 6 integers are passed in registers using \%o0-\%o5 -\item first 8 quad precision floating point args (or 16 double precision, or 32 single precision) are passed in floating point registers (\%q0,\%q4,...,\%q28 or \%d0,\%d2,...,\%d30 or \%f0-\%f32, respectively) -\item for every other argument the stack is used -\item single precision floating point args are passed in odd \%f* registers, and are "right aligned" in their 8-byte space on the stack -\item for every argument passed, corresponding \%o*, \%f* register or stack space is skipped (e.g. passing a doube as 3rd call argument, \%d4 is used and \%o2 is skipped) -\item all arguments \textless=\ 64 bit are passed as 64 bit values -\item minimum stack size is 128 bytes, b/c stack pointer must always point at enough space to store all \%i* and \%l* registers, used when running out of register windows -\item if needed, register spill area (for integer arguments passed via \%o0-\%o5) is adjacent to parameters -\item results are expected by caller to be returned in \%o0-\%o3 (after reg window restore, meaning callee writes to \%i0-\%i3) for integers, \%d0,\%d2,\%d4,\%d6 for floats -\item structs/unions up to 32b, the fields are returned via the respective registers mentioned in the previous bullet point -\item for structs/unions \textgreater= 32b, the caller allocates the space and a pointer to it is passed as hidden first parameter to the function called (meaning in \%o0) -\end{itemize} - -\paragraph{Stack layout} - -Stack directly after function prolog:\\ - -\begin{figure}[h] -\begin{tabular}{5|3|1 1} -\hhline{~-~~} - & \vdots & & \\ -\hhline{~=~~} -local data (and padding) & \hspace{4cm} & & \mrrbrace{8}{caller's frame} \\ -\hhline{~-~~} -\mrlbrace{6}{parameter area} & argument x & \mrrbrace{3}{stack parameters} & \\ - & \ldots & & \\ - & argument 6 & & \\ - & input argument 5 spill & \mrrbrace{3}{spill area} & \\ - & \ldots & & \\ - & input argument 0 spill & & \\ -\hhline{~-~~} -register save area (\%i* and \%l*) & & & \\ -\hhline{~=~~} -local data (and padding) & & & \mrrbrace{3}{current frame} \\ -\hhline{~-~~} -parameter area & & & \\ -\hhline{~-~~} - & \vdots & & \\ -\hhline{~-~~} -\end{tabular} -\\ -\\ -\\ -\caption{Stack layout on sparc64 calling convention} -\end{figure} - +%////////////////////////////////////////////////////////////////////////////// +% +% Copyright (c) 2012-2019 Daniel Adler <dadler@uni-goettingen.de>, +% Tassilo Philipp <tphilipp@potion-studios.com> +% +% Permission to use, copy, modify, and distribute this software for any +% purpose with or without fee is hereby granted, provided that the above +% copyright notice and this permission notice appear in all copies. +% +% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES +% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF +% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR +% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES +% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN +% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF +% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. +% +%////////////////////////////////////////////////////////////////////////////// + +\subsection{SPARC64 Calling Conventions} + +\paragraph{Overview} + +The SPARC family of processors is based on the SPARC instruction set architecture, which comes in basically three revisions, +V7, V8\cite{SPARCV8}\cite{SPARCSysV} and V9\cite{SPARCV9}\cite{SPARCV9SysV}. The former two are 32-bit (see previous chapter) whereas the latter refers to the 64-bit SPARC architecture. +SPARC uses big endian byte order, however, V9 supports also little endian byte order, but for data access only, not instruction access.\\ +\\ +There are two proposals, one from Sun and one from Hal, which disagree on how to handle some aspects of this calling convention.\\ + +\paragraph{\product{dyncall} support} + +\product{dyncall} fully supports the SPARC 64-bit instruction set (V9), for calls and callbacks. + +\subsubsection{SPARC (64-bit) Calling Convention} + +\begin{itemize} +\item 32 double precision floating point registers (d0,d2,d4,...,d62, usable as 16 quad precision ones q0,q4,q8,...g60, and also first half of them are usable as 32 single precision registers f0-f31) +\item 32 64-bit integer/pointer registers out of a bigger (vendor/model dependent) number that are accessible at a time (8 are global ones (g*), whereas the remaining 24 form a register window with 8 input (i*), 8 output (o*) and 8 local (l*) ones) +\item calling a function shifts the register window, the old output registers become the new input registers (old local and input ones are not accessible anymore) +\item stack and frame pointer are offset by a BIAS of 2047 (see official doc for reasons) +\end{itemize} + +\begin{table}[h] +\begin{tabular*}{0.95\textwidth}{lll} +Name & Alias & Brief description\\ +\hline +{\bf \%g0} & \%r0 & Read-only, hardwired to 0 \\ +{\bf \%g1-\%g7} & \%r1-\%r7 & Global \\ +{\bf \%o0-\%o3 and \%i0-\%i3} & \%r8-\%r11 and \%r24-\%r27 & Output and input argument registers, return value \\ +{\bf \%o4,\%o5 and \%i4,\%i5} & \%r12,\%r13 and \%r28,\%r29 & Output and input argument registers \\ +{\bf \%o6 and \%i6} & \%r14 and \%r30, \%sp and \%fp & Stack and frame pointer (NOTE, offset with a BIAS of 2047) \\ +{\bf \%o7 and \%i7} & \%r15 and \%r31 & Return address (caller writes to o7, callee uses i7) \\ +{\bf \%l0-\%l7} & \%r16-\%r23 & preserve \\ +{\bf \%d0,\%d2,\%d4,\%d6} & & scratch, Floating point arguments, return value \\ +{\bf \%d8,\%d10,...,\%d14} & & scratch, Floating point arguments \\ +{\bf \%d16,\%d18,...,\%d30} & & scratch (preserve for Hal), Floating point arguments \\ +{\bf \%d32,\%d34,...,\%d62} & & scratch (preserve for Hal) \\ +\end{tabular*} +\caption{Register usage on sparc64 calling convention} +\end{table} + +\paragraph{Parameter passing} +\begin{itemize} +\item stack grows down +\item stack parameter order: right-to-left +\item caller cleans up the stack +\item stack frame is always aligned to 16 bytes +\item first 6 integers are passed in registers using \%o0-\%o5 +\item first 8 quad precision floating point args (or 16 double precision, or 32 single precision) are passed in floating point registers (\%q0,\%q4,...,\%q28 or \%d0,\%d2,...,\%d30 or \%f0-\%f31, respectively) +\item for every other argument the stack is used +\item single precision floating point args are passed in odd \%f* registers, and are "right aligned" in their 8-byte space on the stack +\item for every argument passed, corresponding \%o*, \%f* register or stack space is skipped (e.g. passing a double as 3rd call argument, \%d4 is used and \%o2 is skipped) +\item all arguments \textless=\ 64 bit are passed as 64 bit values +\item minimum stack size is 128 bytes, b/c stack pointer must always point at enough space to store all \%i* and \%l* registers, used when running out of register windows +\item if needed, register spill area (both, integer and float arguments are spilled in order) is adjacent to parameters +\end{itemize} + +\paragraph{Return values} + +\begin{itemize} +\item results are expected by caller to be returned in \%o0-\%o3 (after reg window restore, meaning callee writes to \%i0-\%i3) for integers +\item \%d0,\%d2,\%d4,\%d6 are used for floating point values +\item the fields of structs/unions up to 32b are returned via the respective registers mentioned in the previous bullet points +\item structs/unions \textgreater= 32b are returned in a space allocated by the caller, with a pointer to it passed as first parameter to the function called (meaning in \%o0) +\end{itemize} + +\paragraph{Stack layout} + +% verified/amended: TP nov 2019 (see also doc/disas_examples/sparc64.sparc64.disas) +Stack directly after function prolog:\\ + +\begin{figure}[h] +\begin{tabular}{5|3|1 1} + & \vdots & & \\ +\hhline{~=~~} +local data (and padding) & \hspace{4cm} & & \mrrbrace{8}{caller's frame} \\ +\hhline{~-~~} +\mrlbrace{6}{parameter area} & arg n-1 & \mrrbrace{3}{stack parameters} & \\ + & \ldots & & \\ + & arg 6 & & \\ + & \%i5 & \mrrbrace{3}{spill area} & \\ + & \ldots & & \\ + & \%i0 & & \\ +\hhline{~-~~} +register save area (\%i* and \%l*) & & & \\ +\hhline{~=~~} +local data (and padding) & & & \mrrbrace{3}{current frame} \\ +\hhline{~-~~} +parameter area & & & \\ +\hhline{~-~~} + & \vdots & & \\ +\end{tabular} +\caption{Stack layout on sparc64 calling convention} +\end{figure} +