mirror of https://github.com/acidanthera/audk.git
026a82abf0
The ADRP instruction in the AArch64 ISA requires the link time and load time offsets of a binary to be equal modulo 4 KB. The reason is that this instruction always produces a multiple of 4 KB, and relies on a subsequent ADD or LDR instruction to set the offset into the page. The resulting symbol reference only produces the correct value if the symbol in question resides at that exact offset into the page, and so loading the binary at arbitrary offsets is not possible. Due to the various levels of padding when packing FVs into FVs into FDs, this alignment is very costly for XIP code, and so we would like to relax this alignment requirement if possible. Given that symbols that are sufficiently close (within 1 MB) of the reference can also be reached using an ADR instruction which does not suffer from this alignment issue, let's replace ADRP instructions with ADR after linking if the offset can be encoded in this instruction's immediate field. Note that this only makes sense if the section alignment is < 4 KB. Otherwise, replacing the ADRP has no benefit, considering that the subsequent ADD or LDR instruction is retained, and that micro-architectures are more likely to be optimized for ADRP/ADD pairs (i.e., via micro op fusing) than for ADR/ADD pairs, which are non-typical. Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org> |
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| .. | ||
| Bin | ||
| BinWrappers/PosixLike | ||
| Conf | ||
| Scripts | ||
| Source | ||
| Tests | ||
| UserManuals | ||
| gcc | ||
| .gitignore | ||
| BuildEnv | ||
| BuildNotes.txt | ||
| Contributions.txt | ||
| GNUmakefile | ||
| License.txt | ||
| Makefile | ||
| ReadMe.txt | ||
| building-gcc.txt | ||
| get_vsvars.bat | ||
| toolsetup.bat | ||
ReadMe.txt
This directory contains the next generation of EDK II build tools and template files. Templates are located in the Conf directory, while the tools executables for Microsoft Windows 32-bit Operating Systems are located in the Bin\Win32 directory, other directory contatins tools source. 1. Build step to generate the binary tools. === Windows/Visual Studio Notes === To build the BaseTools, you should run the standard vsvars32.bat script from your preferred Visual Studio installation or you can run get_vsvars.bat to use latest automatically detected version. In addition to this, you should set the following environment variables: * EDK_TOOLS_PATH - Path to the BaseTools sub directory under the edk2 tree * BASE_TOOLS_PATH - The directory where the BaseTools source is located. (It is the same directory where this README.txt is located.) * PYTHON_FREEZER_PATH - Path to where the python freezer tool is installed After this, you can run the toolsetup.bat file, which is in the same directory as this file. It should setup the remainder of the environment, and build the tools if necessary. Please also refer to the 'BuildNotes.txt' file for more information on building under Windows. === Unix-like operating systems === To build on Unix-like operating systems, you only need to type 'make' in the base directory of the project. === Ubuntu Notes === On Ubuntu, the following command should install all the necessary build packages to build all the C BaseTools: sudo apt-get install build-essential uuid-dev === Python sqlite3 module === On Windows, the cx_freeze will not copy the sqlite3.dll to the frozen binary directory (the same directory as build.exe and GenFds.exe). Please copy it manually from <PythonHome>\DLLs. The Python distributed with most recent Linux will have sqlite3 module built in. If not, please install sqlit3 package separately. 26-OCT-2011