From 3a252a68796878d35d1264dfc520333efb3c8d62 Mon Sep 17 00:00:00 2001
From: Enrico Lumetti <enrico.lumetti@gmail.com>
Date: Sun, 1 May 2022 22:52:32 +0200
Subject: [PATCH] Add CVar to bril translation

---
 cvar-to-bril.rkt      | 50 +++++++++++++++++++++++++++++++++++++++++++
 test-cvar-to-bril.rkt | 25 ++++++++++++++++++++++
 2 files changed, 75 insertions(+)
 create mode 100644 cvar-to-bril.rkt
 create mode 100644 test-cvar-to-bril.rkt

diff --git a/cvar-to-bril.rkt b/cvar-to-bril.rkt
new file mode 100644
index 0000000..dd1e3ed
--- /dev/null
+++ b/cvar-to-bril.rkt
@@ -0,0 +1,50 @@
+#lang racket
+
+(provide cvar-to-bril)
+
+(require (prefix-in bril: bril/lang))
+(require "cvar.rkt")
+
+(define (cvar-to-bril program)
+ (match program
+   [(CProgram _ body)
+    (bril:Program (list
+                   (bril:Function "main" '() '()
+                    (apply append (map cvar-labeled-seq-to-bril body)))))]))
+
+(define (cvar-labeled-seq-to-bril labeled-seq)
+ (match labeled-seq
+  [(cons label seq)
+   (cons
+    (bril:Label (symbol->string label))
+    (cvar-seq-to-bril seq))]))
+
+(define (cvar-seq-to-bril seq)
+ (match seq
+  [(Seq stmt tail)
+   (append
+    (cvar-stmt-to-bril stmt)
+    (cvar-seq-to-bril tail))]
+  [(Return var)
+   (list (bril:EffectInstr 'return (list (symbol->string (Var-name var)))
+                          '() '()))]))
+
+(define (cvar-stmt-to-bril stmt)
+ (match stmt
+  [(Assign (Var varname) rhs) (generate-bril-instrs (symbol->string varname) rhs)]))
+
+(define (generate-bril-instrs dest expr)
+ (match expr
+  [(Int n) 
+   (list (bril:ConstantInstr dest (bril:Type 'int) n))]
+  [(Prim '+ (list (Var v1) (Var v2))) 
+   (list (bril:ValueInstr 'add dest (bril:Type 'int)
+                         (list (symbol->string v1)
+                               (symbol->string v2))
+                         '() '()))]
+  [(Prim '- (list (Var v1))) 
+   (list (bril:ConstantInstr dest (bril:Type 'int) 0)
+         (bril:ValueInstr 'sub dest (bril:Type 'int)
+                          (list dest
+                                (symbol->string v1))
+                          '() '()))]))
diff --git a/test-cvar-to-bril.rkt b/test-cvar-to-bril.rkt
new file mode 100644
index 0000000..4033014
--- /dev/null
+++ b/test-cvar-to-bril.rkt
@@ -0,0 +1,25 @@
+#lang racket
+
+(require "test-util.rkt")
+(require "cvar-to-bril.rkt")
+(require "uniquify.rkt")
+(require "remove-complex-oper.rkt")
+(require "explicate-control.rkt")
+(require "rvar.rkt")
+(require bril/interpreter)
+
+(define listings 
+ (list
+  (Program '() (Prim '+ (list (Int 1) (Int 2))))
+  (Program '() (Prim '+ (list (Prim '- (list (Int 1))) (Int 2))))))
+
+(define (evaluate-bril-main bril-program)
+  (cadr (interp-bril bril-program "main")))
+
+(define (pass program)
+  (cvar-to-bril (explicate-control (remove-complex-opera*-2 (uniquify program)))))
+
+(for ([program listings])
+ (test-eq (interp-RVar (list-ref listings 0))
+          (evaluate-bril-main (pass (list-ref listings 0)))))
+