+;;; Let SP be the stack pointer before CALLing, and FP is the frame
+;;; pointer after the standard prologue. SP +
+;;; FRAME-WORD-OFFSET(SP->FP-OFFSET + I) = FP + FRAME-WORD-OFFSET(I).
+(def!constant sp->fp-offset 2)
+
+(declaim (inline frame-word-offset))
+(defun frame-word-offset (index)
+ (- (1- index)))
+
+(declaim (inline frame-byte-offset))
+(defun frame-byte-offset (index)
+ (* (frame-word-offset index) n-word-bytes))