[llvm] [SeparateConstOffsetFromGEP] Support multiple indices in reorderGEP (PR #92339)

[Jay Foad via llvm-commits]

================
@@ -997,14 +992,12 @@ bool SeparateConstOffsetFromGEP::reorderGEP(GetElementPtrInst *GEP,
   bool PtrGEPInBounds = PtrGEP->isInBounds();
   bool IsChainInBounds = GEPInBounds && PtrGEPInBounds;
   if (IsChainInBounds) {
-    auto GEPIdx = GEP->indices().begin();
-    auto KnownGEPIdx = computeKnownBits(GEPIdx->get(), *DL);
-    IsChainInBounds &= KnownGEPIdx.isNonNegative();
-    if (IsChainInBounds) {
-      auto PtrGEPIdx = PtrGEP->indices().begin();
-      auto KnownPtrGEPIdx = computeKnownBits(PtrGEPIdx->get(), *DL);
-      IsChainInBounds &= KnownPtrGEPIdx.isNonNegative();
-    }
+    auto IsKnownNonNegative = [&](Value *V) {
+      return isKnownNonNegative(V, *DL);
+    };
+    IsChainInBounds &= all_of(GEP->indices(), IsKnownNonNegative);
+    if (IsChainInBounds)
+      IsChainInBounds &= all_of(PtrGEP->indices(), IsKnownNonNegative);
----------------
jayfoad wrote:

Does this work? I'm never sure how flexible `concat` is.
```suggestion
    IsChainInBounds &= all_of(concat(GEP->indices(), PtrGEP->indices()), IsKnownNonNegative);
```

https://github.com/llvm/llvm-project/pull/92339