[llvm] [Sink] Allow sinking of loads to distant blocks (PR #135986)

[via llvm-commits]

================
@@ -27,43 +27,71 @@ using namespace llvm;
 STATISTIC(NumSunk, "Number of instructions sunk");
 STATISTIC(NumSinkIter, "Number of sinking iterations");
 
-static bool isSafeToMove(Instruction *Inst, AliasAnalysis &AA,
-                         SmallPtrSetImpl<Instruction *> &Stores) {
-
-  if (Inst->mayWriteToMemory()) {
-    Stores.insert(Inst);
-    return false;
-  }
-
+static bool hasStoreConflict(Instruction *Inst, AliasAnalysis &AA,
+                             SmallPtrSetImpl<Instruction *> &Stores) {
   if (LoadInst *L = dyn_cast<LoadInst>(Inst)) {
     MemoryLocation Loc = MemoryLocation::get(L);
     for (Instruction *S : Stores)
       if (isModSet(AA.getModRefInfo(S, Loc)))
-        return false;
+        return true;
+  } else if (auto *Call = dyn_cast<CallBase>(Inst)) {
+    for (Instruction *S : Stores)
+      if (isModSet(AA.getModRefInfo(S, Call)))
+        return true;
   }
+  return false;
+}
 
+static bool isSafeToMove(Instruction *Inst, AliasAnalysis &AA,
+                         SmallPtrSetImpl<Instruction *> &Stores) {
+  if (Inst->mayWriteToMemory()) {
+    Stores.insert(Inst);
+    return false;
+  }
   if (Inst->isTerminator() || isa<PHINode>(Inst) || Inst->isEHPad() ||
       Inst->mayThrow() || !Inst->willReturn())
     return false;
-
-  if (auto *Call = dyn_cast<CallBase>(Inst)) {
-    // Convergent operations cannot be made control-dependent on additional
-    // values.
+  // Convergent operations cannot be made control-dependent on additional
+  // values.
----------------
LU-JOHN wrote:

Done.

https://github.com/llvm/llvm-project/pull/135986