[PATCH] D24822: [SelectionDAG] Enable division-by-constant optimization for wide types

[Alexei Starovoitov via llvm-commits]

ast added inline comments.

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Comment at: test/CodeGen/BPF/sdiv_error.ll:3
@@ -2,3 +2,3 @@
 ; RUN: FileCheck %s < %t1
-; CHECK: Unsupport signed division
+; CHECK: Cannot select: t27: i64,i64 = smul_lohi
 
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'cannot select' is unreadable to C programmer comparing to 'Unsupported signed div'.
Usability of BPF is the hardest problem we're facing, so we don't want to lose those error messages. Hence similar to the SDIV error, can you please add the same error for SMUL_LOHI in BPFDAGToDAGISel::Select() ?
Also keeping the same hint "Please convert to unsigned div/mod".
Thanks


https://reviews.llvm.org/D24822