Re: [PATCH v5 0/6] Add ARM support for VS2017

["Gao, Liming" <liming.gao@intel.com>]

Pete:
  The changes in BaseTools and MdePkg are good to me. You can add my R-B.

>-----Original Message-----
>From: Pete Batard [mailto:pete@akeo.ie]
>Sent: Friday, January 12, 2018 9:33 PM
>To: edk2-devel@lists.01.org
>Cc: Gao, Liming <liming.gao@intel.com>; ard.biesheuvel@linaro.org;
>eugene@hp.com
>Subject: [PATCH v5 0/6] Add ARM support for VS2017
>
>(Same as v4, except for the AREA names where we replaced the RVCT macros,
>in
>patch 4/6, so that it matches what would have been produced with the
>macros)
>
>
>The following series adds ARM compilation support for the VS2017 toolchain.
>* PATCH 1 targets the disabling of VS Level 4 warnings. The disabled warnings
>  for ARM are now aligned with IA32 and X64.
>* PATCH 2 adds a NULL handler for the base stack check, since this is a GCC
>  functionality.
>* PATCH 3 updates MdePkg/Library/BaseLib so that the RVCT assembly
>sources
>  are also used for MSFT.
>* PATCH 4 adds the required compiler intrinsics replacements for division,
>  shift, by reusing the RVCT code, as well as memset/memcpy.
>* PATCH 5 adds variable argument handlers for print output. Note that this
>  is done without relying on any external headers, with the VA_ARG macro
>  having been reverse engineered from MSFT ARM assembly output.
>* PATCH 6 enables the selection of ARM in the conf templates.
>
>With these patches, VS2017 toolchain users should be able to compile
>regular UEFI ARM applications using EDK2. Note that, unlike ARM64 support,
>ARM support does not require a specific update of Visual Studio 2017, as
>the ARM toolchain has been available from the very first release.
>
>Additional notes:
>
>We tested compiling and running the full UEFI Shell with this series, as
>well as a small set of applications and drivers, and found no issues.
>With an additional patch [1], it is also possible to use this proposal to
>compile a complete QEMU ARM firmware. As the patch shows, the changes
>that
>need to be applied to the EDK2 sources to achieve this are actually very
>minimal.
>
>However, the generated firmware does not currently boot, possibly because
>of the following warnings being generated by the MS compiler:
>- ArmCpuDxe.dll : warning LNK4072: section count 118 exceeds max (96);
>image may not run
>- UiApp.dll : warning LNK4072: section count 113 exceeds max (96); image may
>not run
>
>As far as I could see, the section count max is hardcoded so a workaround
>would be needed to address those.
>
>Also, because the VS2017 ARM compiler forces a section alignment of 4096
>bytes (which in turn forces use to use /FILEALIGN:4096 as a linker option
>for the firmware generation), the generated firmware exceeds 2MB and we
>had to double its size to 4MB.
>
>At this stage, since the goal of this series is to allow users to compile
>regular ARM UEFI applications using the VS2017 toolchain, I have no plans
>to spend more time on the QEMU firmware issues, especially as I suspect
>that reducing the firmware size back to 2 MB may not be achievable without
>Microsoft altering their compiler. I am however hopeful that ARM
>specialists can take this matter over eventually...
>
>Regards,
>
>/Pete
>
>[1]
>https://github.com/pbatard/edk2/commit/c4ce41094a46f4f3dc7ccc64a906048
>13f037b13
>
>Pete Batard (6):
>  MdePkg: Disable some Level 4 warnings for VS2017/ARM
>  MdePkg/Library/BaseStackCheckLib: Add Null handler for VS2017/ARM
>  MdePkg/Library/BaseLib: Enable VS2017/ARM builds
>  ArmPkg/Library/CompilerIntrinsicsLib: Enable VS2017/ARM builds
>  MdePkg/Include: Add VA list support for VS2017/ARM
>  BaseTools/Conf: Add VS2017/ARM support
>
> ArmPkg/Library/CompilerIntrinsicsLib/Arm/div.asm               | 43 +++++++--
> ArmPkg/Library/CompilerIntrinsicsLib/Arm/ldivmod.asm           | 40 ++++++--
> ArmPkg/Library/CompilerIntrinsicsLib/Arm/llsr.asm              | 22 +++--
> ArmPkg/Library/CompilerIntrinsicsLib/Arm/uldiv.asm             | 29 +++++-
> ArmPkg/Library/CompilerIntrinsicsLib/CompilerIntrinsicsLib.inf | 16 +++-
> ArmPkg/Library/CompilerIntrinsicsLib/memcpy_ms.c               | 34 +++++++
> ArmPkg/Library/CompilerIntrinsicsLib/memset_ms.c               | 33 +++++++
> BaseTools/Conf/build_rule.template                             | 31 ++++++-
> BaseTools/Conf/tools_def.template                              | 31 +++++++
> MdePkg/Include/Arm/ProcessorBind.h                             | 96
>+++++++++++++++-----
> MdePkg/Include/Base.h                                          | 13 +++
> MdePkg/Library/BaseLib/Arm/CpuBreakpoint.asm                   |  5 +-
> MdePkg/Library/BaseLib/BaseLib.inf                             | 16 +++-
> MdePkg/Library/BaseStackCheckLib/BaseStackCheckLib.inf         |  5 +-
> MdePkg/Library/BaseStackCheckLib/BaseStackCheckNull.c          | 18 ++++
> 15 files changed, 372 insertions(+), 60 deletions(-)
> create mode 100644 ArmPkg/Library/CompilerIntrinsicsLib/memcpy_ms.c
> create mode 100644 ArmPkg/Library/CompilerIntrinsicsLib/memset_ms.c
> create mode 100644
>MdePkg/Library/BaseStackCheckLib/BaseStackCheckNull.c
>
>--
>2.9.3.windows.2