[PATCH] D69910: [GVN] Remove duplicated canCoerce tests [NFCI]

[Jameson Nash via Phabricator via llvm-commits]

vtjnash created this revision.
Herald added subscribers: llvm-commits, hiraditya.
Herald added a project: LLVM.

Now that canCoerceMustAliasedValueToLoad should contain the superset of all requirements for coercion to be legal to consider,
we can now remove what should be duplicate tests scattered elsewhere.


Repository:
  rG LLVM Github Monorepo

https://reviews.llvm.org/D69910

Files:
  llvm/lib/Transforms/Utils/VNCoercion.cpp


Index: llvm/lib/Transforms/Utils/VNCoercion.cpp
===================================================================
--- llvm/lib/Transforms/Utils/VNCoercion.cpp
+++ llvm/lib/Transforms/Utils/VNCoercion.cpp
@@ -167,11 +167,6 @@
                                           Value *WritePtr,
                                           uint64_t WriteSizeInBits,
                                           const DataLayout &DL) {
-  // If the loaded or stored value is a first class array or struct, don't try
-  // to transform them.  We need to be able to bitcast to integer.
-  if (LoadTy->isStructTy() || LoadTy->isArrayTy())
-    return -1;
-
   int64_t StoreOffset = 0, LoadOffset = 0;
   Value *StoreBase =
       GetPointerBaseWithConstantOffset(WritePtr, StoreOffset, DL);
@@ -221,21 +216,9 @@
 int analyzeLoadFromClobberingStore(Type *LoadTy, Value *LoadPtr,
                                    StoreInst *DepSI, const DataLayout &DL) {
   auto *StoredVal = DepSI->getValueOperand();
-  
-  // Cannot handle reading from store of first-class aggregate yet.
-  if (StoredVal->getType()->isStructTy() ||
-      StoredVal->getType()->isArrayTy())
+  if (!canCoerceMustAliasedValueToLoad(StoredVal, LoadTy, DL))
     return -1;
 
-  // Don't coerce non-integral pointers to integers or vice versa.
-  if (DL.isNonIntegralPointerType(StoredVal->getType()->getScalarType()) !=
-      DL.isNonIntegralPointerType(LoadTy->getScalarType())) {
-    // Allow casts of zero values to null as a special case
-    auto *CI = dyn_cast<Constant>(StoredVal);
-    if (!CI || !CI->isNullValue())
-      return -1;
-  }
-
   Value *StorePtr = DepSI->getPointerOperand();
   uint64_t StoreSize =
       DL.getTypeSizeInBits(DepSI->getValueOperand()->getType());
@@ -248,23 +231,19 @@
 /// the other load can feed into the second load.
 int analyzeLoadFromClobberingLoad(Type *LoadTy, Value *LoadPtr, LoadInst *DepLI,
                                   const DataLayout &DL) {
-  // Cannot handle reading from store of first-class aggregate yet.
-  if (DepLI->getType()->isStructTy() || DepLI->getType()->isArrayTy())
-    return -1;
-
-  // Don't coerce non-integral pointers to integers or vice versa.
-  if (DL.isNonIntegralPointerType(DepLI->getType()->getScalarType()) !=
-      DL.isNonIntegralPointerType(LoadTy->getScalarType()))
-    return -1;
-
   Value *DepPtr = DepLI->getPointerOperand();
-  uint64_t DepSize = DL.getTypeSizeInBits(DepLI->getType());
-  int R = analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, DepPtr, DepSize, DL);
-  if (R != -1)
-    return R;
+  if (canCoerceMustAliasedValueToLoad(DepLI->getType(), LoadTy, DL)) {
+    uint64_t DepSize = DL.getTypeSizeInBits(DepLI->getType());
+    int R = analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, DepPtr, DepSize, DL);
+    if (R != -1)
+      return R;
+  }
 
-  // If we have a load/load clobber an DepLI can be widened to cover this load,
+  // If we have a load/load clobber and DepLI can be widened to cover this load,
   // then we should widen it!
+  if (!canCoerceMustAliasedValueToLoad(LoadTy, DepLI->getType(), DL))
+    return -1;
+
   int64_t LoadOffs = 0;
   const Value *LoadBase =
       GetPointerBaseWithConstantOffset(LoadPtr, LoadOffs, DL);
@@ -294,13 +273,16 @@
   // If this is memset, we just need to see if the offset is valid in the size
   // of the memset..
   if (MI->getIntrinsicID() == Intrinsic::memset) {
-    if (DL.isNonIntegralPointerType(LoadTy->getScalarType())) {
-      auto *CI = dyn_cast<ConstantInt>(cast<MemSetInst>(MI)->getValue());
-      if (!CI || !CI->isZero())
-        return -1;
-    }
-    return analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, MI->getDest(),
-                                          MemSizeInBits, DL);
+    Value *StoredVal = cast<MemSetInst>(MI)->getValue();
+    if (auto *CI = dyn_cast<Constant>(StoredVal))
+      if (CI->isNullValue())
+        return analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, MI->getDest(),
+                                              MemSizeInBits, DL);
+    Type *StoreTy = IntegerType::get(LoadTy->getContext(), MemSizeInBits);
+    if (canCoerceMustAliasedValueToLoad(StoreTy, LoadTy, DL))
+      return analyzeLoadFromClobberingWrite(LoadTy, LoadPtr, MI->getDest(),
+                                            MemSizeInBits, DL);
+    return -1;
   }
 
   // If we have a memcpy/memmove, the only case we can handle is if this is a


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