Fill in boilerplate for Intel and ARM targets.

The intel, arm32, and arm32 targets were only defined in the meta
language previously. Add Rust implementations too.

This is mostly boilerplate, except for the unit tests in the
registers.rs files.

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

@@ -0,0 +1,73 @@
+//! Intel Instruction Set Architectures.
+
+pub mod settings;
+mod enc_tables;
+mod registers;
+
+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};
+use ir::{InstructionData, DataFlowGraph};
+
+#[allow(dead_code)]
+struct Isa {
+    shared_flags: shared_settings::Flags,
+    isa_flags: settings::Flags,
+    cpumode: &'static [shared_enc_tables::Level1Entry<u16>],
+}
+
+/// Get an ISA builder for creating Intel targets.
+pub fn isa_builder() -> IsaBuilder {
+    IsaBuilder {
+        setup: settings::builder(),
+        constructor: isa_constructor,
+    }
+}
+
+fn isa_constructor(shared_flags: shared_settings::Flags,
+                   builder: &shared_settings::Builder)
+                   -> Box<TargetIsa> {
+    let level1 = if shared_flags.is_64bit() {
+        &enc_tables::LEVEL1_I64[..]
+    } else {
+        &enc_tables::LEVEL1_I32[..]
+    };
+    Box::new(Isa {
+        isa_flags: settings::Flags::new(&shared_flags, builder),
+        shared_flags: shared_flags,
+        cpumode: level1,
+    })
+}
+
+impl TargetIsa for Isa {
+    fn name(&self) -> &'static str {
+        "intel"
+    }
+
+    fn flags(&self) -> &shared_settings::Flags {
+        &self.shared_flags
+    }
+
+    fn register_info(&self) -> &RegInfo {
+        &registers::INFO
+    }
+
+    fn encode(&self, _: &DataFlowGraph, inst: &InstructionData) -> Result<Encoding, Legalize> {
+        lookup_enclist(inst.first_type(),
+                       inst.opcode(),
+                       self.cpumode,
+                       &enc_tables::LEVEL2[..])
+            .and_then(|enclist_offset| {
+                general_encoding(enclist_offset,
+                                 &enc_tables::ENCLISTS[..],
+                                 |instp| enc_tables::check_instp(inst, instp),
+                                 |isap| self.isa_flags.numbered_predicate(isap as usize))
+                    .ok_or(Legalize::Expand)
+            })
+    }
+
+    fn recipe_names(&self) -> &'static [&'static str] {
+        &enc_tables::RECIPE_NAMES[..]
+    }
+}