Sketch of prologue generation

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

@@ -10,9 +10,14 @@ use binemit::{CodeSink, MemoryCodeSink, emit_function};
 use super::super::settings as shared_settings;
 use isa::enc_tables::{self as shared_enc_tables, lookup_enclist, Encodings};
 use isa::Builder as IsaBuilder;
-use isa::{TargetIsa, RegInfo, RegClass, EncInfo};
+use isa::{TargetIsa, RegInfo, RegClass, EncInfo, RegUnit};
+use self::registers::RU;
 use ir;
 use regalloc;
+use result;
+use ir::InstBuilder;
+use legalizer;
+
 
 #[allow(dead_code)]
 struct Isa {
@@ -111,4 +116,44 @@ impl TargetIsa for Isa {
     fn reloc_names(&self) -> &'static [&'static str] {
         &binemit::RELOC_NAMES
     }
+
+    fn prologue_epilogue(&self, func: &mut ir::Function) -> result::CtonResult {
+        use stack_layout::layout_stack;
+        use cursor::{Cursor, EncCursor};
+
+        let word_size = if self.flags().is_64bit() { 8 } else { 4 };
+        let stack_size = layout_stack(&mut func.stack_slots, word_size)?;
+
+        // Append frame pointer to function signature
+        let rbp_arg = ir::AbiParam::special_reg(
+            ir::types::I64,
+            ir::ArgumentPurpose::FramePointer,
+            RU::rbp as RegUnit,
+        );
+        func.signature.params.push(rbp_arg);
+
+        // Append param to entry EBB
+        let entry_ebb = func.layout.entry_block().expect("missing entry block");
+        func.dfg.append_ebb_param(entry_ebb, ir::types::I64);
+
+        // Find our frame pointer parameter Value
+        let fp = func.special_param(ir::ArgumentPurpose::FramePointer)
+            .expect("missing frame pointer");
+
+        // Assign it a location
+        func.locations[fp] = ir::ValueLoc::Reg(RU::rbp as RegUnit);
+
+        // Insert prologue
+        let mut pos = EncCursor::new(func, self).at_first_insertion_point(entry_ebb);
+        pos.ins().x86_push(fp);
+        pos.ins().copy_special(
+            RU::rbp as RegUnit,
+            RU::rsp as RegUnit,
+        );
+        pos.ins().adjust_sp_imm(-(stack_size as i32));
+
+        //legalizer::legalize_function(func, &mut func.cfg, self);
+
+        Ok(())
+    }
 }