Fixing up stack pad in Fraud.

Author: dvanhorn

ziggy/src/compile-ops.rkt

@@ -1,6 +1,6 @@
 #lang crook
 {:= B C D0 D1 E0 E1 F}
-(provide {:> E0} compile-op0 compile-op1 {:> F} compile-op2)
+(provide {:> E0} compile-op0 compile-op1 {:> F} compile-op2 {:> F} pad-stack)
 (require "ast.rkt")
 {:> D0} (require "types.rkt")
 (require a86/ast)
@@ -151,3 +151,17 @@
        (Jl 'err)
        (Cmp rax (value->bits 255))
        (Jg 'err)))
+
+{:> F} ;; Asm
+{:> F} ;; Dynamically pad the stack to be aligned for a call
+{:> F}
+(define pad-stack
+  (seq (Mov r15 rsp)
+       (And r15 #b1000)
+       (Sub rsp r15)))
+
+{:> F} ;; Asm
+{:> F} ;; Undo the stack alignment after a call
+{:> F}
+(define unpad-stack
+  (seq (Add rsp r15)))

ziggy/src/compile.rkt

@@ -27,6 +27,7 @@
         (Ret)
         {:> E1} ;; Error handler
         {:> E1} (Label 'err)
+        {:> F}  pad-stack
         {:> E1} (Call 'raise_error)))
 
 {:> F} ;; type CEnv = (Listof [Maybe Id])