[SVE][CodeGen] Scalable vector MVT size queries

* Implements scalable size queries for MVTs, split out from D53137.

* Contains a fix for FindMemType to avoid using scalable vector type
  to contain non-scalable types.

* Explicit casts for several places where implicit integer sign
  changes or promotion from 32 to 64 bits caused problems.

* CodeGenDAGPatterns will treat scalable and non-scalable vector types
  as different.

Reviewers: greened, cameron.mcinally, sdesmalen, rovka

Reviewed By: rovka

Differential Revision: https://reviews.llvm.org/D66871

1 files changed, 3 insertions, 1 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 1b02f96cf27..abd046530ed 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -8842,7 +8842,9 @@ MemSDNode::MemSDNode(unsigned Opc, unsigned Order, const DebugLoc &dl,
   // We check here that the size of the memory operand fits within the size of
   // the MMO. This is because the MMO might indicate only a possible address
   // range instead of specifying the affected memory addresses precisely.
-  assert(memvt.getStoreSize() <= MMO->getSize() && "Size mismatch!");
+  // TODO: Make MachineMemOperands aware of scalable vectors.
+  assert(memvt.getStoreSize().getKnownMinSize() <= MMO->getSize() &&
+         "Size mismatch!");
 }
 
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