forked from OSchip/llvm-project
075e5a2e2b
It caused PR34564. > This is a preparatory step for D34515 and also is being recommitted as its > first version caused PR34045. > > This change: > - makes nodes ISD::ADDCARRY and ISD::SUBCARRY legal for i32 > - lowering is done by first converting the boolean value into the carry flag > using (_, C) ← (ARMISD::ADDC R, -1) and converted back to an integer value > using (R, _) ← (ARMISD::ADDE 0, 0, C). An ARMISD::ADDE between the two > operations does the actual addition. > - for subtraction, given that ISD::SUBCARRY second result is actually a > borrow, we need to invert the value of the second operand and result before > and after using ARMISD::SUBE. We need to invert the carry result of > ARMISD::SUBE to preserve the semantics. > - given that the generic combiner may lower ISD::ADDCARRY and > ISD::SUBCARRYinto ISD::UADDO and ISD::USUBO we need to update their lowering > as well otherwise i64 operations now would require branches. This implies > updating the corresponding test for unsigned. > - add new combiner to remove the redundant conversions from/to carry flags > to/from boolean values (ARMISD::ADDC (ARMISD::ADDE 0, 0, C), -1) → C > - fixes PR34045 > > Differential Revision: https://reviews.llvm.org/D35192 llvm-svn: 312980 |
||
|---|---|---|
| .. | ||
| Analysis | ||
| Assembler | ||
| Bindings | ||
| Bitcode | ||
| BugPoint | ||
| CodeGen | ||
| DebugInfo | ||
| DllTool | ||
| Examples | ||
| ExecutionEngine | ||
| Feature | ||
| FileCheck | ||
| Instrumentation | ||
| Integer | ||
| JitListener | ||
| LTO | ||
| LibDriver | ||
| Linker | ||
| MC | ||
| Object | ||
| ObjectYAML | ||
| Other | ||
| SafepointIRVerifier | ||
| SymbolRewriter | ||
| TableGen | ||
| ThinLTO/X86 | ||
| Transforms | ||
| Unit | ||
| Verifier | ||
| YAMLParser | ||
| tools | ||
| .clang-format | ||
| CMakeLists.txt | ||
| TestRunner.sh | ||
| lit.cfg | ||
| lit.site.cfg.in | ||