Re: [PATCH v3] docs/misra: document the expected sizes of integer types

[Stefano Stabellini <sstabellini@xxxxxxxxxx>]

On Thu, 4 Apr 2024, Bertrand Marquis wrote:
> Hi Stefano,
> 
> > On 4 Apr 2024, at 03:12, Stefano Stabellini <sstabellini@xxxxxxxxxx> wrote:
> > 
> > Xen makes assumptions about the size of integer types on the various
> > architectures. Document these assumptions.
> > 
> > Signed-off-by: Stefano Stabellini <stefano.stabellini@xxxxxxx>
> > ---
> > Changes in v3:
> > - add links to System V, AAPCS32 and AAPCS64
> > 
> > ---
> > docs/misra/C-language-toolchain.rst | 69 +++++++++++++++++++++++++++++
> > 1 file changed, 69 insertions(+)
> > 
> > diff --git a/docs/misra/C-language-toolchain.rst 
> > b/docs/misra/C-language-toolchain.rst
> > index b7c2000992..84b21992bc 100644
> > --- a/docs/misra/C-language-toolchain.rst
> > +++ b/docs/misra/C-language-toolchain.rst
> > @@ -480,4 +480,73 @@ The table columns are as follows:
> >      - See Section "4.13 Preprocessing Directives" of GCC_MANUAL and 
> > Section "11.1 Implementation-defined behavior" of CPP_MANUAL.
> > 
> > 
> > +Sizes of Integer types
> > +______________________
> > +
> > +Xen expects System V ABI on x86_64:
> > +  https://gitlab.com/x86-psABIs/x86-64-ABI
> > +
> > +Xen expects AAPCS32 on ARMv8-A AArch32:
> > +  https://github.com/ARM-software/abi-aa/blob/main/aapcs32/aapcs32.rst
> > +
> > +Xen expects AAPCS64 LP64 on ARMv8-A AArch64:
> > +  https://github.com/ARM-software/abi-aa/blob/main/aapcs64/aapcs64.rst
> 
> We still support armv7 somehow so we should add something for it here.
> 
> > +
> > +A summary table of data types, sizes and alignment is below:
> > +
> > +.. list-table::
> > +   :widths: 10 10 10 45
> > +   :header-rows: 1
> > +
> > +   * - Type
> > +     - Size
> > +     - Alignment
> > +     - Architectures
> > +
> > +   * - char 
> > +     - 8 bits
> > +     - 8 bits
> > +     - all architectures
> > +
> > +   * - short
> > +     - 16 bits
> > +     - 16 bits
> > +     - all architectures
> > +
> > +   * - int
> > +     - 32 bits
> > +     - 32 bits
> > +     - all architectures
> > +
> > +   * - long
> > +     - 32 bits
> > +     - 32 bits 
> > +     - 32-bit architectures (x86_32, ARMv8-A AArch32, ARMv8-R AArch32)
> 
> Same here armv7 should be mentioned.
> 
> > +
> > +   * - long
> > +     - 64 bits
> > +     - 64 bits 
> > +     - 64-bit architectures (x86_64, ARMv8-A AArch64, RV64, PPC64)
> > +
> > +   * - long long
> > +     - 64-bit
> > +     - 32-bit
> > +     - x86_32
> > +
> > +   * - long long
> > +     - 64-bit
> > +     - 64-bit
> > +     - 64-bit architectures, ARMv8-A AArch32, ARMv8-R AArch32
> 
> Should this be all architecture except x86_32 ?

yes

> > +
> > +   * - pointer
> > +     - 32-bit
> > +     - 32-bit
> > +     - 32-bit architectures (x86_32, ARMv8-A AArch32, ARMv8-R AArch32)
> 
> Armv7 missing here.

What is the formal name I should use for it here? ARMv7 AArch32 ?