[llvm] [RISCV] Implement RISCVTTIImpl::getPreferredAddressingMode for HasVendorXCVmem (PR #120533)

[Philipp van Kempen via llvm-commits]

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@@ -2329,6 +2329,15 @@ unsigned RISCVTTIImpl::getMaximumVF(unsigned ElemWidth, unsigned Opcode) const {
   return std::max<unsigned>(1U, RegWidth.getFixedValue() / ElemWidth);
 }
 
+TTI::AddressingModeKind
+RISCVTTIImpl::getPreferredAddressingMode(const Loop *L,
+                                         ScalarEvolution *SE) const {
+  if (ST->hasVendorXCVmem())
+    return TTI::AMK_PostIndexed;
+
+  return TTI::AMK_None;
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PhilippvK wrote:

Instead of returning `TTI::AMK_None`, I should probably call the generic `getPreferredAddressingMode` implementation?

https://github.com/llvm/llvm-project/pull/120533