[llvm] [Target][RISCV] Add HwMode support to subregister index size/offset. (PR #86368)

[Craig Topper via llvm-commits]

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@@ -1399,28 +1406,47 @@ CodeGenSubRegIndex *CodeGenRegBank::getConcatSubRegIndex(
 
   // None exists, synthesize one.
   std::string Name = Parts.front()->getName();
-  // Determine whether all parts are contiguous.
-  bool IsContinuous = true;
-  unsigned Size = Parts.front()->Size;
-  unsigned LastOffset = Parts.front()->Offset;
-  unsigned LastSize = Parts.front()->Size;
   const unsigned UnknownSize = (uint16_t)-1;
+
   for (unsigned i = 1, e = Parts.size(); i != e; ++i) {
     Name += '_';
     Name += Parts[i]->getName();
-    if (Size == UnknownSize || Parts[i]->Size == UnknownSize)
-      Size = UnknownSize;
-    else
-      Size += Parts[i]->Size;
-    if (LastSize == UnknownSize || Parts[i]->Offset != (LastOffset + LastSize))
-      IsContinuous = false;
-    LastOffset = Parts[i]->Offset;
-    LastSize = Parts[i]->Size;
   }
+
   Idx = createSubRegIndex(Name, Parts.front()->getNamespace());
-  Idx->Size = Size;
-  Idx->Offset = IsContinuous ? Parts.front()->Offset : -1;
   Idx->ConcatenationOf.assign(Parts.begin(), Parts.end());
+
+  unsigned NumModes = CGH.getNumModeIds();
+  for (unsigned M = 0; M < NumModes; ++M) {
+    const CodeGenSubRegIndex *Part = Parts.front();
+
+    // Determine whether all parts are contiguous.
+    bool IsContinuous = true;
+    const SubRegRange &FirstPartRange = Part->Range.get(M);
+    unsigned Size = FirstPartRange.Size;
+    unsigned LastOffset = FirstPartRange.Offset;
+    unsigned LastSize = FirstPartRange.Size;
+
+    for (unsigned i = 1, e = Parts.size(); i != e; ++i) {
+      Part = Parts[i];
+      Name += '_';
+      Name += Part->getName();
+
+      const SubRegRange &PartRange = Part->Range.get(M);
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topperc wrote:

`Range.get(M)` will return the value from the DefaultMode if the mode isn't present.

https://github.com/llvm/llvm-project/pull/86368