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Summary: SimplifyFPBinOp is a variant of SimplifyBinOp that lets you specify fast math flags, but the name is misleading because both functions can simplify both FP and non-FP ops. Instead, overload SimplifyBinOp so that you can optionally specify fast math flags. Likewise for SimplifyFPUnOp. Reviewers: spatel Reviewed By: spatel Subscribers: xbolva00, cameron.mcinally, eraman, hiraditya, haicheng, zzheng, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D64902 llvm-svn: 366902
Analysis Opportunities: //===---------------------------------------------------------------------===// In test/Transforms/LoopStrengthReduce/quadradic-exit-value.ll, the ScalarEvolution expression for %r is this: {1,+,3,+,2}<loop> Outside the loop, this could be evaluated simply as (%n * %n), however ScalarEvolution currently evaluates it as (-2 + (2 * (trunc i65 (((zext i64 (-2 + %n) to i65) * (zext i64 (-1 + %n) to i65)) /u 2) to i64)) + (3 * %n)) In addition to being much more complicated, it involves i65 arithmetic, which is very inefficient when expanded into code. //===---------------------------------------------------------------------===// In formatValue in test/CodeGen/X86/lsr-delayed-fold.ll, ScalarEvolution is forming this expression: ((trunc i64 (-1 * %arg5) to i32) + (trunc i64 %arg5 to i32) + (-1 * (trunc i64 undef to i32))) This could be folded to (-1 * (trunc i64 undef to i32)) //===---------------------------------------------------------------------===//