Hi Andrew, Attachment and below are my build map files and code size for your suggested two modules with CLANGLTO38 and VS2013x86. Maybe I should use latest VS2015x86 for the comparing next time.
* CLANGLTO38: > build -a IA32 -t CLANGLTO38 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > IntelFrameworkModulePkg/Universal/StatusCode/Pei/StatusCodePei.inf -b RELEASE 1,184 > build -a IA32 -t CLANGLTO38 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > IntelFrameworkModulePkg/Universal/StatusCode/Pei/StatusCodePei.inf -b DEBUG > -DDEBUG_ON_SERIAL_PORT 7,648 > build -a X64 -t CLANGLTO38 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > PcAtChipsetPkg/8254TimerDxe/8254Timer.inf -b RELEASE 1,600 > build -a X64 -t CLANGLTO38 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > PcAtChipsetPkg/8254TimerDxe/8254Timer.inf -b DEBUG -DDEBUG_ON_SERIAL_PORT 11,712 (with -fno-lto to disable lto in MdePkg\Library\BasePrintLib\BasePrintLib.inf, which is to work around CPU exception in PrintLib during boot time) 8,736 (with lto enalbed in BasePrintLib.inf) * VS2013x86: > build -a IA32 -t VS2013x86 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > IntelFrameworkModulePkg/Universal/StatusCode/Pei/StatusCodePei.inf -b RELEASE 1,280 > build -a IA32 -t VS2013x86 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > IntelFrameworkModulePkg/Universal/StatusCode/Pei/StatusCodePei.inf -b DEBUG > -DDEBUG_ON_SERIAL_PORT 8,576 > build -a X64 -t VS2013x86 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > PcAtChipsetPkg/8254TimerDxe/8254Timer.inf -b RELEASE 1,760 > build -a X64 -t VS2013x86 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > PcAtChipsetPkg/8254TimerDxe/8254Timer.inf -b DEBUG -DDEBUG_ON_SERIAL_PORT 9,760 I believe the clang3.8 with LTO enabled is good enough on code size. My current biggest trouble is the Clang3.8 LTO not stable on GNU ld when generate X64 code, and worse on gold (even cannot finish build). I've reported two bugs about LTO against GNU ld and gold in below, FYI. https://sourceware.org/bugzilla/show_bug.cgi?id=20062 https://sourceware.org/bugzilla/show_bug.cgi?id=20070 BTW, does XCODE linker have linux version? If yes, I'd like to try it to co-work with clang 3.8 as CC compiler. Steven Shi Intel\SSG\STO\UEFI Firmware Tel: +86 021-61166522 iNet: 821-6522 > -----Original Message----- > From: af...@apple.com [mailto:af...@apple.com] > Sent: Wednesday, May 11, 2016 11:09 PM > To: Shi, Steven <steven....@intel.com> > Cc: edk2-devel@lists.01.org > Subject: Re: [edk2] edk2 llvm branch > > > > On May 11, 2016, at 5:08 AM, Shi, Steven > > <steven....@intel.com<mailto:steven....@intel.com>> wrote: > > > > Hi Andrew, > > From your data, it looks the XCode LTO is not enabled correctly for IA32, > but correct for X64. Attachment has my build map files, and below are my > build commands. FYI. > > > > Sorry had a typo in the tools_def.txt, here are the numbers with -flto > correctly added to the CC_FLAGS: > > > build -a IA32 -t XCODE5 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > MdeModulePkg/Core/Pei/PeiMain.inf -b RELEASE > 25K > > build -a IA32 -t XCODE5 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > MdeModulePkg/Core/Pei/PeiMain.inf -b DEBUG - > DDEBUG_ON_SERIAL_PORT > 45K > > build -a X64 -t XCODE5 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > MdeModulePkg/Core/Dxe/DxeMain.inf -b RELEASE > 103K > > build -a X64 -t XCODE5 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > MdeModulePkg/Core/Dxe/DxeMain.inf -b DEBUG - > DDEBUG_ON_SERIAL_PORT > 133K > > When doing size optimizations it is often easier to start with smaller > drivers. > Can you send the sizes/map files for: > > build -a IA32 -t XCODE5 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > IntelFrameworkModulePkg/Universal/StatusCode/Pei/StatusCodePei.inf -b > RELEASE > 1220 > > build -a IA32 -t XCODE5 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > IntelFrameworkModulePkg/Universal/StatusCode/Pei/StatusCodePei.inf -b > DEBUG -DDEBUG_ON_SERIAL_PORT > 8228 > > build -a X64 -t XCODE5 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > PcAtChipsetPkg/8254TimerDxe/8254Timer.inf -b RELEASE > 2464 > > build -a X64 -t XCODE5 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > PcAtChipsetPkg/8254TimerDxe/8254Timer.inf -b DEBUG - > DDEBUG_ON_SERIAL_PORT > 9088 > > > > I forgot to mention that X64 XCODE5/clang has a 5 byte overhead per > function vs.VS2013x86 due to supporting stack unwind. The upside is the > unexpected exception handler can print out a stack trace. VS2013x86 > requires the debugger with symbols to unwind the stack. > > ~/work/Compiler>cat call.c > int main () > { > return 0; > } > ~/work/Compiler>clang -Os call.c > ~/work/Compiler>lldb a.out > (lldb) target create "a.out" > Current executable set to 'a.out' (x86_64). > (lldb) dis -m -b -n main > a.out`main > a.out`main: > a.out[0x100000f98] <+0>: 55 pushq %rbp > a.out[0x100000f99] <+1>: 48 89 e5 movq %rsp, %rbp > a.out[0x100000f9c] <+4>: 31 c0 xorl %eax, %eax > a.out[0x100000f9e] <+6>: 5d popq %rbp > a.out[0x100000f9f] <+7>: c3 retq > > Thanks, > > Andrew Fish > > > VS2013x86: > > build -a IA32 -t VS2013x86 -p OvmfPkg\OvmfPkgIa32.dsc -n 5 -m > MdeModulePkg\Core\Pei\PeiMain.inf -b RELEASE > > build -a IA32 -t VS2013x86 -p OvmfPkg\OvmfPkgIa32.dsc -n 5 -m > MdeModulePkg\Core\Pei\PeiMain.inf -b DEBUG - > DDEBUG_ON_SERIAL_PORT > > build -a X64 -t VS2013x86 -p OvmfPkg\OvmfPkgX64.dsc -n 5 -m > MdeModulePkg\Core\Dxe\DxeMain.inf -b RELEASE > > build -a X64 -t VS2013x86 -p OvmfPkg\OvmfPkgX64.dsc -n 5 -m > MdeModulePkg\Core\Dxe\DxeMain.inf -b DEBUG - > DDEBUG_ON_SERIAL_PORT > > > > CLANGLTO38: > > build -a IA32 -t CLANGLTO38 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > MdeModulePkg/Core/Pei/PeiMain.inf -b RELEASE > > build -a IA32 -t CLANGLTO38 -p OvmfPkg/OvmfPkgIa32.dsc -n 5 -m > MdeModulePkg/Core/Pei/PeiMain.inf -b DEBUG - > DDEBUG_ON_SERIAL_PORT > > build -a X64 -t CLANGLTO38 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > MdeModulePkg/Core/Dxe/DxeMain.inf -b RELEASE > > build -a X64 -t CLANGLTO38 -p OvmfPkg/OvmfPkgX64.dsc -n 5 -m > MdeModulePkg/Core/Dxe/DxeMain.inf -b DEBUG - > DDEBUG_ON_SERIAL_PORT > > > > > > > > Steven Shi > > Intel\SSG\STO\UEFI Firmware > > > > Tel: +86 021-61166522 > > iNet: 821-6522 > > > > From: af...@apple.com<mailto:af...@apple.com> [mailto:af...@apple.com] > > Sent: Wednesday, May 11, 2016 2:03 AM > > To: Shi, Steven <steven....@intel.com<mailto:steven....@intel.com>> > > Cc: edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org> > > Subject: Re: [edk2] edk2 llvm branch > > > > > > On May 10, 2016, at 8:05 AM, Shi, Steven > <steven....@intel.com<mailto:steven....@intel.com<mailto:steven....@intel.com%3cmailto:steven....@intel.com>>> > wrote: > > > > Hi Andrew, > > Thank you for the suggestion. I will try your suggestion and response other > questions in your email later. I don't have XCODE5 environment, but could do > me a favor and let me know what current XCODE5 code size for PeiCore.efi > and DxeCore.efi in your side? In my side, as below data show, I see the LTO > can bring big code size improvement which is quite important for firmware in > many scenarios. > > > > I forgot to mention. LTO or not it is good to check to make sure the > assembly files are getting dead stripped. For example check to make sure you > are not getting all the assembly functions in the BaseLib included in your > executable. Some of the assembly is .S and some is .nasm so you may see > different behavior depending on which assembler was used. > > > > It is also useful to start looking at the smallest PEIM/DXE drivers 1st as > > it > may be easier to spot what is different. > > > > > > Maybe it is also a good idea to enable LTO in XCODE. > > > > For Xcode you add -object_path_lto > $(DEST_DIR_DEBUG)/$(BASE_NAME).lto to *_XCODE5_*_DLINK_FLAGS. > This places the intermediate link code gen in the Build/ director vs. a temp > director and is important for source level debugging. To turn LTO on and off > you add -flto to *_XCODE5_*_CC_FLAGS . > > > > We ended up making LTO a configurable build option, so we control it in > the DSC file. git > > > > [BuildOptions] > > !if $(PEI_LTO_ENABLE) > > XCODE:*_*_IA32_PLATFORM_FLAGS = -flto > > !endif > > > > !if $(DXE_LTO_ENABLE) > > XCODE:*_*_X64_PLATFORM_FLAGS = -flto > > !endif > > > > I included the Xcode 6.3.2 Numbers: > > > > > > > > > > IA32 DEBUG PeiCore.efi on Ovmf build code size example: > > ToolChainName PeiCore.efi file size > > VS2013x86: 40KB > > CLANGLTO38: 42KB > > Xcode 61K > > > > > > GCCLTO53: 44KB > > GCC49: 55KB > > CLANG38: 60KB > > > > > > IA32 RELEASE PeiCore.efi on Ovmf build code size example: > > ToolChainName PeiCore.efi file size > > VS2013x86: 20KB > > GCCLTO53: 23KB > > CLANGLTO38: 24KB > > Xcode 31K > > > > > > > > GCC49: 27KB > > Clang38: 29KB > > > > > > X64 DEBUG DxeCore.efi on Ovmf build code size example: > > ToolChainName .efi file size LZMA > > Compressed size > > VS2013x86: 137KB > > 57KB > > CLANGLTO38: 145KB > > 61KB > > Xcode 157K 68K > > > > > > GCCLTO53: 161KB > > 63KB > > GCC49: 273KB 69KB > > CLANG38: 205KB > > 72KB > > > > > > > > X64 RELEASE DxeCore.efi on Ovmf build code size example: > > ToolChainName .efi file size LZMA > > Compressed size > > VS2013x86: 95KB > > 44KB > > GCCLTO53: 101KB > > 46KB > > CLANGLTO38: 107KB > > 48KB > > Xcode 104K 49K > > > > > > GCC49: 184KB 52KB > > CLANG38: 133KB > > 53KB > > > > > > Can you send my linker map files for VS2013 & CLANGLTO38 off list. > > > > Thanks, > > > > Andrew Fish > > > > > > Steven Shi > > Intel\SSG\STO\UEFI Firmware > > > > Tel: +86 021-61166522 > > iNet: 821-6522 > > > >> -----Original Message----- > >> From: > >> af...@apple.com<mailto:af...@apple.com<mailto:af...@apple.com%3cmailto:af...@apple.com>> > [mailto:af...@apple.com] > >> Sent: Tuesday, May 10, 2016 1:12 PM > >> To: Shi, Steven > >> <steven....@intel.com<mailto:steven....@intel.com<mailto:steven....@intel.com%3cmailto:steven....@intel.com>>> > >> Cc: > >> edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org%3cmailto:edk2-devel@lists.01.org>> > >> Subject: Re: [edk2] edk2 llvm branch > >> > >> > > > > _______________________________________________ > > edk2-devel mailing list > > edk2-devel@lists.01.org<mailto:edk2-devel@lists.01.org> > > https://lists.01.org/mailman/listinfo/edk2-devel _______________________________________________ edk2-devel mailing list edk2-devel@lists.01.org https://lists.01.org/mailman/listinfo/edk2-devel
