Juneyoung Lee
06829034ca
Revert "[ConstantFold] Fold more operations to poison"
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This reverts commit 53040a968dc2ff20931661e55f05da2ef8b964a0 due to its
bad interaction with select i1 -> and/or i1 transformation.
This fixes:
https://bugs.llvm.org/show_bug.cgi?id=49005
https://bugs.llvm.org/show_bug.cgi?id=48435
2021-02-04 00:24:02 +09:00
Juneyoung Lee
9c49dcc356
[ConstantFold] Don't fold and/or i1 poison to poison (NFC)
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.. because it causes miscompilation when combined with select i1 -> and/or.
It is the select fold which is incorrect; but it is costly to disable the fold, so hack this one.
D92270
2020-11-30 22:58:31 +09:00
Juneyoung Lee
53040a968d
[ConstantFold] Fold more operations to poison
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This patch folds more operations to poison.
Alive2 proof: https://alive2.llvm.org/ce/z/mxcb9G (it does not contain tests about div/rem because they fold to poison when raising UB)
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D92270
2020-11-29 21:19:48 +09:00
Juneyoung Lee
c6b62efb91
[ConstantFold] Fold operations to poison if possible
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This patch updates ConstantFold, so operations are folded into poison if possible.
<alive2 proofs>
casts: https://alive2.llvm.org/ce/z/WSj7rw
binary operations (arithmetic): https://alive2.llvm.org/ce/z/_7dEyJ
binary operations (bitwise): https://alive2.llvm.org/ce/z/cezjVN
vector/aggregate operations: https://alive2.llvm.org/ce/z/BQ7hWz
unary ops: https://alive2.llvm.org/ce/z/yBRs4q
other ops: https://alive2.llvm.org/ce/z/iXbcFD
Reviewed By: nikic
Differential Revision: https://reviews.llvm.org/D92203
2020-11-29 02:28:40 +09:00
