[llvm] [RISCV] Set the exact flag on the SRL created for converting vscale to a read of vlenb. (PR #144571)

[Craig Topper via llvm-commits]

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@@ -7360,20 +7360,25 @@ SDValue RISCVTargetLowering::LowerOperation(SDValue Op,
     uint64_t Val = Op.getConstantOperandVal(0);
     if (isPowerOf2_64(Val)) {
       uint64_t Log2 = Log2_64(Val);
-      if (Log2 < 3)
+      if (Log2 < 3) {
+        SDNodeFlags Flags;
+        Flags.setExact(true);
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topperc wrote:

I forgot to pass the Flags to getNode. New patch coming as soon as tests finish.

https://github.com/llvm/llvm-project/pull/144571