[PATCH] D30914: [Outliner] Add outliner for AArch64

[Matthias Braun via Phabricator via llvm-commits]

MatzeB added inline comments.


================
Comment at: lib/Target/AArch64/AArch64InstrInfo.cpp:1410-1463
+  // Check if the offset is in the range.
+  switch(MI.getOpcode()) {
+    // Unsigned instructions.
+    default:
+      return (Offset >= 0 && Offset <= 4095);
+
+    // Signed instructions with 9 bit offsets.
----------------
Seeing that this is another instance of information about every load/store instruction. How about emitting this information as well if we go for something like getMemOpInfo()?


================
Comment at: lib/Target/AArch64/AArch64InstrInfo.h:223
+    }
+  }
+
----------------
We should only put short and performance critical functions into a header (and well templates force you sometimes).

It shouldn't be too hard to share code with `getMemOpBaseRegImmOfsWidth()` and for maintenance reasons we really should do so:

- Add a new function similar to this:
```
/// Returns true if opcode \p Opc is a memory operation and set \p Scale and \p Width
/// accordingly.
bool getMemOpInfo(unsigned Opcode, unsigned &Scale, unsigned &Width) {
   switch (Opc) {
      // Move stuff from getMemOpBaseRegImmOfsWidth() here
   }
}

bool AArch64InstrInfo::getMemOpBaseRegImmOfsWidth(...) {
   // ... keep the beginning as is ...
   unsigned Scale = 0;
   if (!getMemOpInfo(LdSt.getOpcode(), Width, Scale))
     return false;
   // ... keep end as is ...
}

// Every use of getScale() can now call getMemOpInfo() and just ignore the Width value
```


https://reviews.llvm.org/D30914