TableGen support for auto-generating assembly two-operand aliases.

Assembly matchers for instructions with a two-operand form. ARM is full
of these, for example:
  add {Rd}, Rn, Rm  // Rd is optional and is the same as Rn if omitted.

The property TwoOperandAliasConstraint on the instruction definition controls
when, and if, an alias will be formed. No explicit InstAlias definitions
are required.

rdar://11255754

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@155172 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 2 insertions, 0 deletions

diff --git a/include/llvm/Target/Target.td b/include/llvm/Target/Target.td
index fa1ec55..6a321ea 100644
--- a/include/llvm/Target/Target.td
+++ b/include/llvm/Target/Target.td
@@ -402,6 +402,8 @@ class Instruction {
 
   string AsmMatchConverter = "";
 
+  string TwoOperandAliasConstraint = "";
+
   ///@}
 }