FailedChanges

Summary

  1. [ARM] Use ADDCARRY / SUBCARRY This patch: - 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::SUBCARRY into 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 Differential Revision: https://reviews.llvm.org/D35192
Revision 309923 by rogfer01:
[ARM] Use ADDCARRY / SUBCARRY

This patch:

- 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::SUBCARRY into 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

Differential Revision: https://reviews.llvm.org/D35192
Change TypePath in RepositoryPath in Workspace
The file was modified/llvm/trunk/lib/Target/ARM/ARMISelLowering.cppllvm.src/lib/Target/ARM/ARMISelLowering.cpp
The file was modified/llvm/trunk/lib/Target/ARM/ARMISelLowering.hllvm.src/lib/Target/ARM/ARMISelLowering.h
The file was modified/llvm/trunk/test/CodeGen/ARM/intrinsics-overflow.llllvm.src/test/CodeGen/ARM/intrinsics-overflow.ll