forked from OSchip/llvm-project
7e5937b775
32-bit x86 Windows targets use a linked-list of nodes allocated on the stack, referenced to via thread-local storage. The personality routine interprets one of the fields in the node as a 'state number' which indicates where the personality routine should transfer control. State transitions are possible only before call-sites which may throw exceptions. Our previous scheme had us update the state number before all call-sites which may throw. Instead, we can try to minimize the number of times we need to store by reasoning about the nearest store which dominates the current call-site. If the last store agrees with the current call-site, then we know that the state-update is redundant and can be elided. This is largely straightforward: an RPO walk of the blocks allows us to correctly forward propagate the information when the function is a DAG. Currently, loops are not handled optimally and may trigger superfluous state stores. Differential Revision: http://reviews.llvm.org/D16763 llvm-svn: 261122 |
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| clang | ||
| clang-tools-extra | ||
| compiler-rt | ||
| debuginfo-tests | ||
| libclc | ||
| libcxx | ||
| libcxxabi | ||
| libunwind | ||
| lld | ||
| lldb | ||
| llgo | ||
| llvm | ||
| openmp | ||
| polly | ||