Do not model all INLINEASM instructions as having unmodelled side effects.

Instead encode llvm IR level property "HasSideEffects" in an operand (shared
with IsAlignStack). Added MachineInstrs::hasUnmodeledSideEffects() to check
the operand when the instruction is an INLINEASM.

This allows memory instructions to be moved around INLINEASM instructions.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@123044 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/TargetInstrInfoImpl.cpp

@@ -329,8 +329,13 @@ isReallyTriviallyReMaterializableGeneric(const MachineInstr *MI,
   const TargetInstrDesc &TID = MI->getDesc();
 
   // Avoid instructions obviously unsafe for remat.
-  if (TID.hasUnmodeledSideEffects() || TID.isNotDuplicable() ||
-      TID.mayStore())
+  if (TID.isNotDuplicable() || TID.mayStore() ||
+      MI->hasUnmodeledSideEffects())
+    return false;
+
+  // Don't remat inline asm. We have no idea how expensive it is
+  // even if it's side effect free.
+  if (MI->isInlineAsm())
     return false;
 
   // Avoid instructions which load from potentially varying memory.