[llvm][TypeSize] Fix addition/subtraction in TypeSize. (#72979)

It seems TypeSize is currently broken in the sense that:

  TypeSize::Fixed(4) + TypeSize::Scalable(4) => TypeSize::Fixed(8)

without failing its assert that explicitly tests for this case:

  assert(LHS.Scalable == RHS.Scalable && ...);

The reason this fails is that `Scalable` is a static method of class
TypeSize,
and LHS and RHS are both objects of class TypeSize. So this is
evaluating
if the pointer to the function Scalable == the pointer to the function
Scalable,
which is always true because LHS and RHS have the same class.

This patch fixes the issue by renaming `TypeSize::Scalable` ->
`TypeSize::getScalable`, as well as `TypeSize::Fixed` to
`TypeSize::getFixed`,
so that it no longer clashes with the variable in
FixedOrScalableQuantity.

The new methods now also better match the coding standard, which
specifies that:
* Variable names should be nouns (as they represent state)
* Function names should be verb phrases (as they represent actions)

1 files changed, 2 insertions, 2 deletions

diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 0b392e7..8c6c112 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -1597,7 +1597,7 @@ static bool valueCoversEntireFragment(Type *ValTy, DbgVariableIntrinsic *DII) {
   const DataLayout &DL = DII->getModule()->getDataLayout();
   TypeSize ValueSize = DL.getTypeAllocSizeInBits(ValTy);
   if (std::optional<uint64_t> FragmentSize = DII->getFragmentSizeInBits())
-    return TypeSize::isKnownGE(ValueSize, TypeSize::Fixed(*FragmentSize));
+    return TypeSize::isKnownGE(ValueSize, TypeSize::getFixed(*FragmentSize));
 
   // We can't always calculate the size of the DI variable (e.g. if it is a
   // VLA). Try to use the size of the alloca that the dbg intrinsic describes
@@ -1623,7 +1623,7 @@ static bool valueCoversEntireFragment(Type *ValTy, DPValue *DPV) {
   const DataLayout &DL = DPV->getModule()->getDataLayout();
   TypeSize ValueSize = DL.getTypeAllocSizeInBits(ValTy);
   if (std::optional<uint64_t> FragmentSize = DPV->getFragmentSizeInBits())
-    return TypeSize::isKnownGE(ValueSize, TypeSize::Fixed(*FragmentSize));
+    return TypeSize::isKnownGE(ValueSize, TypeSize::getFixed(*FragmentSize));
 
   // We can't always calculate the size of the DI variable (e.g. if it is a
   // VLA). Try to use the size of the alloca that the dbg intrinsic describes