forked from OSchip/llvm-project
a6f57ad2c9
To determine the list of clobbered registers, the RegUsageInfoCollector pass uses the list of callee saved registers provided by the target and then augments it with the list of registers which have all their subregisters saved. It then basically does the difference between all the registers and the saved registers to come up with what is clobbered (plus it checks that the register is defined within that functions). The patch fixes a bug where when register does not have any subregister lane, hence when checking if any of its subregister are not saved, we would find none and think the register is saved as well. That's obviously wrong. The code was actually kind of checking for something like that with the CoveredBySubRegs bit. What this bit says is that a register is completely covered by its subregisters. We required that this bit was set, to check that a register was saved by its subregister lanes, since without this bit, we potentially would miss to check some part of the register. However, this bit is used de facto on registers that don't have any subregisters (e.g., on ARM) and the code was not prepared for that. This patch fixes this by checking that a register has subregisters before declaring it saved when none of its lanes are modified. llvm-svn: 361901 |
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| clang | ||
| clang-tools-extra | ||
| compiler-rt | ||
| debuginfo-tests | ||
| libclc | ||
| libcxx | ||
| libcxxabi | ||
| libunwind | ||
| lld | ||
| lldb | ||
| llgo | ||
| llvm | ||
| openmp | ||
| parallel-libs | ||
| polly | ||
| pstl | ||
| .arcconfig | ||
| .clang-format | ||
| .clang-tidy | ||
| .gitignore | ||
| README.md | ||
README.md
The LLVM Compiler Infrastructure
This directory and its subdirectories contain source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and runtime environments.