[Mlir-commits] [mlir] [mlir][arith] Add result pretty printing for constant vscale values (PR #83565)

[Andrzej Warzyński]

================
@@ -400,6 +400,35 @@ OpFoldResult arith::MulIOp::fold(FoldAdaptor adaptor) {
       [](const APInt &a, const APInt &b) { return a * b; });
 }
 
+void arith::MulIOp::getAsmResultNames(
+    function_ref<void(Value, StringRef)> setNameFn) {
+  if (!isa<IndexType>(getType()))
+    return;
+
+  // Match vector.vscale by name to avoid depending on the vector dialect (which
+  // is a circular dependency).
+  auto isVscale = [](Operation *op) {
+    return op && op->getName().getStringRef() == "vector.vscale";
+  };
+
+  // Name `base * vscale` or `vscale * base` as `c<base_value>_vscale`.
+  IntegerAttr baseValue;
+  if (matchPattern(getLhs(), m_Constant(&baseValue)) &&
+      isVscale(getRhs().getDefiningOp())) {
+    // base * vscale
+  } else if (isVscale(getLhs().getDefiningOp()) &&
+             matchPattern(getRhs(), m_Constant(&baseValue))) {
+    // vscale * base
+  } else {
+    return;
+  }
----------------
banach-space wrote:

Could we avoid `if/else-if` nests? How about:

```suggestion
  bool isVscaleXBase = matchPattern(getLhs(), m_Constant(&baseValue)) &&
      isVscale(getRhs().getDefiningOp());
  bool isBaseXVscale = isVscale(getLhs().getDefiningOp()) &&
             matchPattern(getRhs(), m_Constant(&baseValue));
  if (!(isVscaleXBase || isBaseXVscale)
    return;
```

https://github.com/llvm/llvm-project/pull/83565