diff options
Diffstat (limited to 'libguile/frames.h')
| -rw-r--r-- | libguile/frames.h | 76 |
1 files changed, 36 insertions, 40 deletions
diff --git a/libguile/frames.h b/libguile/frames.h index 31f86345f..c2f1e57db 100644 --- a/libguile/frames.h +++ b/libguile/frames.h @@ -1,4 +1,4 @@ -/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013, 2014 Free Software Foundation, Inc. +/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013, 2014, 2015 Free Software Foundation, Inc. * * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License @@ -38,24 +38,29 @@ Stack frame layout ------------------ - /------------------\ - | Local N-1 | <- sp | ... | - | Local 1 | - | Local 0 | <- fp = SCM_FRAME_LOCALS_ADDRESS (fp) - +==================+ + +==================+ <- fp + 2 = SCM_FRAME_PREVIOUS_SP (fp) + | Dynamic link | + +------------------+ | Return address | - | Dynamic link | <- fp - 2 = SCM_FRAME_LOWER_ADDRESS (fp) - +==================+ - | | <- fp - 3 = SCM_FRAME_PREVIOUS_SP (fp) + +==================+ <- fp + | Local 0 | + +------------------+ + | Local 1 | + +------------------+ + | ... | + +------------------+ + | Local N-1 | + \------------------/ <- sp + + The stack grows down. The calling convention is that a caller prepares a stack frame consisting of the saved FP and the return address, followed by the procedure and then the arguments to the call, in order. Thus in the beginning of a call, the procedure being called is in slot 0, the first argument is in slot 1, and the SP points to the last argument. - The number of arguments, including the procedure, is thus SP - FP + - 1. + The number of arguments, including the procedure, is thus FP - SP. After ensuring that the correct number of arguments have been passed, a function will set the stack pointer to point to the last local @@ -80,35 +85,26 @@ -/* This structure maps to the contents of a VM stack frame. It can - alias a frame directly. */ -struct scm_vm_frame +/* Each element on the stack occupies the same amount of space. */ +union scm_vm_stack_element { - SCM *dynamic_link; - scm_t_uint32 *return_address; - SCM locals[1]; /* Variable-length */ -}; - -#define SCM_FRAME_LOWER_ADDRESS(fp) (((SCM *) (fp)) - 2) -#define SCM_FRAME_STRUCT(fp) \ - ((struct scm_vm_frame *) SCM_FRAME_LOWER_ADDRESS (fp)) -#define SCM_FRAME_LOCALS_ADDRESS(fp) (SCM_FRAME_STRUCT (fp)->locals) - -#define SCM_FRAME_PREVIOUS_SP(fp) (((SCM *) (fp)) - 3) + union scm_vm_stack_element *fp; + scm_t_uint32 *ip; + SCM scm; -#define SCM_FRAME_RETURN_ADDRESS(fp) \ - (SCM_FRAME_STRUCT (fp)->return_address) -#define SCM_FRAME_SET_RETURN_ADDRESS(fp, ra) \ - SCM_FRAME_STRUCT (fp)->return_address = (ra) -#define SCM_FRAME_DYNAMIC_LINK(fp) \ - (SCM_FRAME_STRUCT (fp)->dynamic_link) -#define SCM_FRAME_SET_DYNAMIC_LINK(fp, dl) \ - SCM_FRAME_DYNAMIC_LINK (fp) = (dl) -#define SCM_FRAME_LOCAL(fp,i) \ - (SCM_FRAME_STRUCT (fp)->locals[i]) + /* For GC purposes. */ + void *ptr; + scm_t_bits bits; +}; -#define SCM_FRAME_NUM_LOCALS(fp, sp) \ - ((sp) + 1 - &SCM_FRAME_LOCAL (fp, 0)) +#define SCM_FRAME_PREVIOUS_SP(fp_) ((fp_) + 2) +#define SCM_FRAME_RETURN_ADDRESS(fp_) ((fp_)[0].ip) +#define SCM_FRAME_SET_RETURN_ADDRESS(fp_, ra) ((fp_)[0].ip = (ra)) +#define SCM_FRAME_DYNAMIC_LINK(fp_) ((fp_)[1].fp) +#define SCM_FRAME_SET_DYNAMIC_LINK(fp_, dl) ((fp_)[1].fp = (dl)) +#define SCM_FRAME_SLOT(fp_,i) ((fp_) - (i) - 1) +#define SCM_FRAME_LOCAL(fp_,i) (SCM_FRAME_SLOT (fp_, i)->scm) +#define SCM_FRAME_NUM_LOCALS(fp_, sp) ((fp_) - (sp)) /* @@ -137,13 +133,13 @@ enum scm_vm_frame_kind #define SCM_VM_FRAME_STACK_HOLDER(f) SCM_VM_FRAME_DATA (f)->stack_holder #define SCM_VM_FRAME_FP_OFFSET(f) SCM_VM_FRAME_DATA (f)->fp_offset #define SCM_VM_FRAME_SP_OFFSET(f) SCM_VM_FRAME_DATA (f)->sp_offset -#define SCM_VM_FRAME_FP(f) (SCM_VM_FRAME_FP_OFFSET (f) + scm_i_frame_stack_base (f)) -#define SCM_VM_FRAME_SP(f) (SCM_VM_FRAME_SP_OFFSET (f) + scm_i_frame_stack_base (f)) +#define SCM_VM_FRAME_FP(f) (scm_i_frame_stack_top (f) - SCM_VM_FRAME_FP_OFFSET (f)) +#define SCM_VM_FRAME_SP(f) (scm_i_frame_stack_top (f) - SCM_VM_FRAME_SP_OFFSET (f)) #define SCM_VM_FRAME_IP(f) SCM_VM_FRAME_DATA (f)->ip #define SCM_VM_FRAME_OFFSET(f) scm_i_frame_offset (f) #define SCM_VALIDATE_VM_FRAME(p,x) SCM_MAKE_VALIDATE (p, x, VM_FRAME_P) -SCM_INTERNAL SCM* scm_i_frame_stack_base (SCM frame); +SCM_INTERNAL union scm_vm_stack_element* scm_i_frame_stack_top (SCM frame); SCM_INTERNAL scm_t_ptrdiff scm_i_frame_offset (SCM frame); /* See notes in frames.c before using this. */ |