[flang-commits] [flang] [flang] Support non-index shape/shift/slice for CG box operations. (PR #124625)

[Tom Eccles via flang-commits]

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@@ -1675,22 +1675,26 @@ struct EmboxCommonConversion : public fir::FIROpConversion<OP> {
     this->attachTBAATag(storeOp, boxTy, boxTy, nullptr);
     return storage;
   }
-};
 
-/// Compute the extent of a triplet slice (lb:ub:step).
-static mlir::Value
-computeTripletExtent(mlir::ConversionPatternRewriter &rewriter,
-                     mlir::Location loc, mlir::Value lb, mlir::Value ub,
-                     mlir::Value step, mlir::Value zero, mlir::Type type) {
-  mlir::Value extent = rewriter.create<mlir::LLVM::SubOp>(loc, type, ub, lb);
-  extent = rewriter.create<mlir::LLVM::AddOp>(loc, type, extent, step);
-  extent = rewriter.create<mlir::LLVM::SDivOp>(loc, type, extent, step);
-  // If the resulting extent is negative (`ub-lb` and `step` have different
-  // signs), zero must be returned instead.
-  auto cmp = rewriter.create<mlir::LLVM::ICmpOp>(
-      loc, mlir::LLVM::ICmpPredicate::sgt, extent, zero);
-  return rewriter.create<mlir::LLVM::SelectOp>(loc, cmp, extent, zero);
-}
+  /// Compute the extent of a triplet slice (lb:ub:step).
+  mlir::Value computeTripletExtent(mlir::ConversionPatternRewriter &rewriter,
+                                   mlir::Location loc, mlir::Value lb,
+                                   mlir::Value ub, mlir::Value step,
+                                   mlir::Value zero, mlir::Type type) const {
+    lb = this->integerCast(loc, rewriter, type, lb);
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tblah wrote:

why are the `this->` pointers required?

https://github.com/llvm/llvm-project/pull/124625