Re: [edk2-devel] [Patch 0/4 V4] Enhance Incremental Build

["Bob Feng" <bob.c.feng@intel.com>]

Hi Mike,

A tool chain enable this feature by defining the *_<tool chain name>_*_DEPS_FLAGS  in tools_def and applying $(DEPS_FLAGS) in build_rule.txt.
I have added those setting for MSVC, GCC, CLANG tool chain in tools_def.template and build_rule.template. Those exist tool chains are all enable this feature by default.

Only RVCT tool chain does not support this feature, but according to https://bugzilla.tianocore.org/show_bug.cgi?id=1750, RVCT will be dropped from our support tool chains.

So is it fine to add comments for each tool chain to document this tool chain is enabled to generate dependency files in build_rule.template?

Thanks,
Bob

-----Original Message-----
From: Kinney, Michael D 
Sent: Friday, December 6, 2019 12:49 AM
To: devel@edk2.groups.io; Feng, Bob C <bob.c.feng@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>
Subject: RE: [edk2-devel] [Patch 0/4 V4] Enhance Incremental Build

Hi Bob,

How does a tool chain opt-in or opt-out of this feature?

As you point out, not all tool chains provide the information needed to support this feature.  We need to make sure the use of this feature or not is clearly documented in the profile for each tool chain.

Thanks,

Mike

> -----Original Message-----
> From: devel@edk2.groups.io <devel@edk2.groups.io> On Behalf Of Bob 
> Feng
> Sent: Thursday, December 5, 2019 12:18 AM
> To: devel@edk2.groups.io
> Subject: [edk2-devel] [Patch 0/4 V4] Enhance Incremental Build
> 
> V4: Move .deps files to where corresponding .obj file locate
> V3: Change CLANG9 to CLANGPDB according to commit 14672c34bd
> V2: Fixed a bug in patch 4/4.
> 
> Incremental build reduces the build time by only building the module 
> that need to update. Edk2 Build system is a Makefile based build 
> system. The incrememtal build ability is provided by the Make program. 
> But Edk2 build tool need to generate correct makefile to have Make 
> program do incremental build correctly.
> 
> The current solution in build tool to support incremental build is 
> that build tool find out the include file list for each source file of 
> a module, and in module's makefile, build tool add the include file 
> list as the source file's dependency.
> In this way Make program can decide if it need to rebuild a source 
> code by checking its dependency. This solution has 2 shortcommings, 
> one is the process of finding include list is slow, the other is this 
> method can't handle case that a MACRO in #include statement so the 
> related source file is always built.
> 
> This patch provides another method to support incremental build. That 
> is to use c preprocessor and trim tool to generate dependency files 
> for the source file.
> This method will save much time in AutoGen phase and handle MACRO in 
> #include correctly.
> 
> For C files:
>     1. MSVS.
>         cl.exe has a build option /showIncludes to display include 
> files on stdout. Build tool captures
>         that messages and generate dependency files, .deps files.
>     2. CLANG and GCC
>         -MMD -MF build option are used to generate dependency files by 
> preprocessor. Build tool updates the
>        .deps files.
> 
> For ASL files:
>     1. Trim find out all the included files, which are asl specific 
> include format, and generate .trim.deps file.
>     2. ASL PP use c preprocessor to find out all included files with 
> #include format and generate a .deps file
>     3. build tool updates the .deps file
> 
> For ASM files (.asm, .s or .nasm):
>     1. Trim find out all the included files, which are asm specific 
> include format, and generate .trim.deps file.
>     2. ASM PP use c preprocessor to find out all included files with 
> #include format and generate a deps file
>     3. build tool updates the .deps file
> 
> Build tool add "include" instruction for those deps files in the 
> Makefile.
> 
> This patch does not support RVCT tool chain for the BZ
> https://bugzilla.tianocore.org/show_bug.cgi?id=1750
> 
> Feng, Bob C (4):
>   BaseTools: Add build option for dependency file generation
>   BaseTools: Generate dependent files for ASL and ASM files
>   BaseTools: Update build_rule.txt to generate dependent files.
>   BaseTools: Enhance Basetool for incremental build
> 
>  BaseTools/Conf/build_rule.template            |  94
> ++++---
>  BaseTools/Conf/tools_def.template             | 173
> ++++++------
>  BaseTools/Source/Python/AutoGen/GenMake.py    |  83
> ++----
>  .../Source/Python/AutoGen/IncludesAutoGen.py  | 255
> ++++++++++++++++++
>  .../Source/Python/AutoGen/ModuleAutoGen.py    |  23 ++
>  BaseTools/Source/Python/Trim/Trim.py          | 115
> ++++++--
>  BaseTools/Source/Python/build/build.py        |  63
> ++++-
>  7 files changed, 588 insertions(+), 218 deletions(-)  create mode 
> 100644 BaseTools/Source/Python/AutoGen/IncludesAutoGen.py
> 
> --
> 2.20.1.windows.1
> 
> 
>