[llvm] [RISCV][GlobalIsel] Remove redundant sext.w for ADDIW (PR #159597)

[Craig Topper via llvm-commits]

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@@ -147,6 +147,11 @@ def : Pat<(i32 (trunc GPR:$src)), (COPY GPR:$src)>;
 def : Pat<(zext_is_sext (i32 GPR:$src)), (ADDIW GPR:$src, 0)>;
 }
 
+let Predicates = [IsRV64, NoStdExtF] in {
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topperc wrote:

Why do we need NoStdExtF?

https://github.com/llvm/llvm-project/pull/159597