[PATCH] D157603: [RISCV] Truncate constants to EltSize when combine store of BUILD_VECTOR

[Wang Pengcheng via Phabricator via llvm-commits]

wangpc marked 3 inline comments as done.
wangpc added inline comments.


================
Comment at: llvm/lib/Target/RISCV/RISCVISelLowering.cpp:13486
           continue;
-        NewC.insertBits(Val.getConstantOperandAPInt(i),
-                        i * Val.getScalarValueSizeInBits());
+        NewC.insertBits(Val.getConstantOperandAPInt(i).zextOrTrunc(EleSize),
+                        i * EleSize);
----------------
craig.topper wrote:
> wangpc wrote:
> > craig.topper wrote:
> > > Why does it need to be `zextOrTrunc`? Can it just be `trunc`? It never need to be extended right?
> > Actually I don't know, here is just defensive programming.
> I would use trunc so we get the assertion. If we did need to extend for some reason, I don't know that zero extend would be correct.
OK, it makes sense to me.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D157603/new/

https://reviews.llvm.org/D157603