[llvm] [DAGCombine] Propagate truncate to operands (PR #98666)

[Simon Pilgrim via llvm-commits]

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@@ -2975,6 +2975,8 @@ class TargetLoweringBase {
     return isTruncateFree(Val.getValueType(), VT2);
   }
 
+  virtual bool shouldReduceRegisterPressure() const { return false; }
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RKSimon wrote:

Have you tried removing it? The isZExtFree check is usually to limit the fold on x86 (where only i32->i64 is typically free) - some of the time its actually superfluous.

https://github.com/llvm/llvm-project/pull/98666