20faf78919
Thinlink provides an opportunity to propagate function attributes across modules, enabling additional propagation opportunities. This change propagates (currently default off, turn on with `disable-thinlto-funcattrs=1`) noRecurse and noUnwind based off of function summaries of the prevailing functions in bottom-up call-graph order. Testing on clang self-build: 1. There's a 35-40% increase in noUnwind functions due to the additional propagation opportunities. 2. Throughput is measured at 10-15% increase in thinlink time which itself is 1.5% of E2E link time. Implementation-wise this adds the following summary function attributes: 1. noUnwind: function is noUnwind 2. mayThrow: function contains a non-call instruction that `Instruction::mayThrow` returns true on (e.g. windows SEH instructions) 3. hasUnknownCall: function contains calls that don't make it into the summary call-graph thus should not be propagated from (e.g. indirect for now, could add no-opt functions as well) Testing: Clang self-build passes and 2nd stage build passes check-all ninja check-all with newly added tests passing Reviewed By: tejohnson Differential Revision: https://reviews.llvm.org/D36850 |
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| .. | ||
| BitWriter.cpp | ||
| BitcodeWriter.cpp | ||
| BitcodeWriterPass.cpp | ||
| CMakeLists.txt | ||
| ValueEnumerator.cpp | ||
| ValueEnumerator.h | ||