[llvm] [RISCV][GISel] Don't custom legalize load/store of vector of pointers if ELEN < XLEN. (PR #101565)

[Craig Topper via llvm-commits]

================
@@ -302,38 +317,28 @@ RISCVLegalizerInfo::RISCVLegalizerInfo(const RISCVSubtarget &ST)
                                                {nxv8s32, p0, nxv8s32, 32},
                                                {nxv16s32, p0, nxv16s32, 32}});
 
-  auto &ExtLoadActions =
-      getActionDefinitionsBuilder({G_SEXTLOAD, G_ZEXTLOAD})
-          .legalForTypesWithMemDesc({{s32, p0, s8, 8}, {s32, p0, s16, 16}});
-  if (XLen == 64) {
-    LoadStoreActions.legalForTypesWithMemDesc({{s64, p0, s8, 8},
-                                               {s64, p0, s16, 16},
-                                               {s64, p0, s32, 32},
-                                               {s64, p0, s64, 64}});
-    ExtLoadActions.legalForTypesWithMemDesc(
-        {{s64, p0, s8, 8}, {s64, p0, s16, 16}, {s64, p0, s32, 32}});
-  } else if (ST.hasStdExtD()) {
-    LoadStoreActions.legalForTypesWithMemDesc({{s64, p0, s64, 64}});
-  }
-  if (ST.hasVInstructions() && ST.getELen() == 64)
-    LoadStoreActions.legalForTypesWithMemDesc({{nxv1s8, p0, nxv1s8, 8},
-                                               {nxv1s16, p0, nxv1s16, 16},
-                                               {nxv1s32, p0, nxv1s32, 32}});
+    if (ST.getELen() == 64)
+      LoadStoreActions.legalForTypesWithMemDesc({{nxv1s8, p0, nxv1s8, 8},
+                                                 {nxv1s16, p0, nxv1s16, 16},
+                                                 {nxv1s32, p0, nxv1s32, 32}});
+
+    if (ST.hasVInstructionsI64())
+      LoadStoreActions.legalForTypesWithMemDesc({{nxv1s64, p0, nxv1s64, 64},
+                                                 {nxv2s64, p0, nxv2s64, 64},
+                                                 {nxv4s64, p0, nxv4s64, 64},
+                                                 {nxv8s64, p0, nxv8s64, 64}});
 
-  if (ST.hasVInstructionsI64())
-    LoadStoreActions.legalForTypesWithMemDesc({{nxv1s64, p0, nxv1s64, 64},
+    // we will take the custom lowering logic if we have scalable vector types
+    // with non-standard alignments
+    LoadStoreActions.customIf(typeIsLegalIntOrFPVec(0, IntOrFPVecTys, ST));
 
-                                               {nxv2s64, p0, nxv2s64, 64},
-                                               {nxv4s64, p0, nxv4s64, 64},
-                                               {nxv8s64, p0, nxv8s64, 64}});
+    // Pointers require that XLen sized elements are legal.
+    if (XLen <= ST.getELen())
+      LoadStoreActions.customIf(typeIsLegalPtrVec(0, PtrVecTys, ST));
----------------
topperc wrote:

We don't seem to have marked any pointer vectors with legalIf. I think they just go to the custom handler and get treated as legal if they pass the alignment check.

https://github.com/llvm/llvm-project/pull/101565