Move encoding-related information into an EncInfo struct.

The tables returned by recipe_names() and recipe_constraints() are now
collected into an EncInfo struct that is available from
TargetIsa::encoding_info(). This is equivalent to the register bank
tables available fro TargetIsa::register_info().

This cleans of the TargetIsa interface and makes it easier to add
encoding-related information.

lib/cretonne/src/isa/intel/mod.rs

@@ -9,7 +9,7 @@ use binemit::CodeSink;
 use super::super::settings as shared_settings;
 use isa::enc_tables::{self as shared_enc_tables, lookup_enclist, general_encoding};
 use isa::Builder as IsaBuilder;
-use isa::{TargetIsa, RegInfo, Encoding, Legalize, RecipeConstraints};
+use isa::{TargetIsa, RegInfo, EncInfo, Encoding, Legalize};
 use ir;
 
 #[allow(dead_code)]
@@ -55,6 +55,10 @@ impl TargetIsa for Isa {
         registers::INFO.clone()
     }
 
+    fn encoding_info(&self) -> EncInfo {
+        enc_tables::INFO.clone()
+    }
+
     fn encode(&self,
               dfg: &ir::DataFlowGraph,
               inst: &ir::InstructionData)
@@ -72,14 +76,6 @@ impl TargetIsa for Isa {
                 })
     }
 
-    fn recipe_names(&self) -> &'static [&'static str] {
-        &enc_tables::RECIPE_NAMES[..]
-    }
-
-    fn recipe_constraints(&self) -> &'static [RecipeConstraints] {
-        &enc_tables::RECIPE_CONSTRAINTS
-    }
-
     fn emit_inst(&self, func: &ir::Function, inst: ir::Inst, sink: &mut CodeSink) {
         binemit::emit_inst(func, inst, sink)
     }