[PATCH] D81900: Add coverage for inexact constant folding for multiplication in Selection DAG

[Michael Berg via Phabricator via llvm-commits]

mcberg2017 marked an inline comment as done.
mcberg2017 added inline comments.


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Comment at: llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp:5139-5140
+          RHS.multiply(LHS, APFloat::rmNearestTiesToEven);
+      if (((status & APFloat::opInexact) == 0) ||
+          getTarget().Options.UnsafeFPMath) {
+        return getConstantFP(RHS, DL, VT);
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arsenm wrote:
> I'm not sure I understand why this would depend on unsafe math. Why does it matter if it was inexact? The unconstrained operations have the defined rounding mode
With Unsafe any contracts concerning the ability to deliver infinite precision are broken, ergo Unsafe overrides and allows the result regardless as precision is relaxed and its behavior as well.


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  https://reviews.llvm.org/D81900/new/

https://reviews.llvm.org/D81900