[llvm] 05cd9a0 - [ConstantFold] Simplify type check in reinterpret load folding (NFC)

[Nikita Popov via llvm-commits]

Author: Nikita Popov
Date: 2022-01-21T09:06:35+01:00
New Revision: 05cd9a0596d8d2cc4fdb1d1dfa0957968aceaf92

URL: https://github.com/llvm/llvm-project/commit/05cd9a0596d8d2cc4fdb1d1dfa0957968aceaf92
DIFF: https://github.com/llvm/llvm-project/commit/05cd9a0596d8d2cc4fdb1d1dfa0957968aceaf92.diff

LOG: [ConstantFold] Simplify type check in reinterpret load folding (NFC)

Keep a list of allowed types, but then always construct the map
type the same way. We need an integer with the same width as the
original type.

Added: 
    

Modified: 
    llvm/lib/Analysis/ConstantFolding.cpp

Removed: 
    


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diff  --git a/llvm/lib/Analysis/ConstantFolding.cpp b/llvm/lib/Analysis/ConstantFolding.cpp
index 253a7243bcf59..d42086a10ee14 100644
--- a/llvm/lib/Analysis/ConstantFolding.cpp
+++ b/llvm/lib/Analysis/ConstantFolding.cpp
@@ -553,23 +553,16 @@ Constant *FoldReinterpretLoadFromConst(Constant *C, Type *LoadTy,
 
   // If this isn't an integer load we can't fold it directly.
   if (!IntType) {
-    // If this is a float/double load, we can try folding it as an int32/64 load
-    // and then bitcast the result.  This can be useful for union cases.  Note
+    // If this is a non-integer load, we can try folding it as an int load and
+    // then bitcast the result.  This can be useful for union cases.  Note
     // that address spaces don't matter here since we're not going to result in
     // an actual new load.
-    Type *MapTy;
-    if (LoadTy->isHalfTy())
-      MapTy = Type::getInt16Ty(C->getContext());
-    else if (LoadTy->isFloatTy())
-      MapTy = Type::getInt32Ty(C->getContext());
-    else if (LoadTy->isDoubleTy())
-      MapTy = Type::getInt64Ty(C->getContext());
-    else if (LoadTy->isVectorTy()) {
-      MapTy = PointerType::getIntNTy(
-          C->getContext(), DL.getTypeSizeInBits(LoadTy).getFixedSize());
-    } else
+    if (!LoadTy->isHalfTy() && !LoadTy->isFloatTy() && !LoadTy->isDoubleTy() &&
+        !LoadTy->isVectorTy())
       return nullptr;
 
+    Type *MapTy = Type::getIntNTy(
+          C->getContext(), DL.getTypeSizeInBits(LoadTy).getFixedSize());
     if (Constant *Res = FoldReinterpretLoadFromConst(C, MapTy, Offset, DL)) {
       if (Res->isNullValue() && !LoadTy->isX86_MMXTy() &&
           !LoadTy->isX86_AMXTy())