-/* Copyright (C) 2001, 2009, 2010, 2011, 2012 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
- * as published by the Free Software Foundation; either version 3 of
- * the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
- * 02110-1301 USA
- */
-
-#ifndef _SCM_FRAMES_H_
-#define _SCM_FRAMES_H_
-
-#include <libguile.h>
-#include "programs.h"
-
-\f
-/*
- * VM frames
- */
-
-/*
- * It's a little confusing, but there are two representations of frames in this
- * file: frame pointers and Scheme objects wrapping those frame pointers. The
- * former uses the SCM_FRAME_... macro prefix, the latter SCM_VM_FRAME_..
- * prefix.
- *
- * The confusing thing is that only Scheme frame objects have functions that use
- * them, and they use the scm_frame_.. prefix. Hysterical raisins.
- */
-
-/* VM Frame Layout
- ---------------
-
- | ... |
- | Intermed. val. 0 | <- fp + nargs + nlocs
- +------------------+
- | Local variable 1 |
- | Local variable 0 | <- fp + nargs
- | Argument 1 |
- | Argument 0 | <- fp = SCM_FRAME_STACK_ADDRESS (fp)
- | Program | <- fp - 1
- +==================+
- | Return address | <- SCM_FRAME_UPPER_ADDRESS (fp)
- | MV return address|
- | Dynamic link | <- fp - 4 = SCM_FRAME_DATA_ADDRESS (fp) = SCM_FRAME_LOWER_ADDRESS (fp)
- +==================+
- | |
-
- As can be inferred from this drawing, it is assumed that
- `sizeof (SCM *) == sizeof (SCM)', since pointers (the `link' parts) are
- assumed to be as long as SCM objects. */
-
-/* This structure maps to the contents of a VM stack frame. It can
- alias a frame directly. */
-struct scm_vm_frame
-{
- SCM *dynamic_link;
- scm_t_uint8 *mv_return_address;
- scm_t_uint8 *return_address;
- SCM program;
- SCM stack[1]; /* Variable-length */
-};
-
-#define SCM_FRAME_STRUCT(fp) \
- ((struct scm_vm_frame *) SCM_FRAME_DATA_ADDRESS (fp))
-
-#define SCM_FRAME_DATA_ADDRESS(fp) (((SCM *) (fp)) - 4)
-#define SCM_FRAME_STACK_ADDRESS(fp) (SCM_FRAME_STRUCT (fp)->stack)
-#define SCM_FRAME_UPPER_ADDRESS(fp) ((SCM*)&SCM_FRAME_STRUCT (fp)->return_address)
-#define SCM_FRAME_LOWER_ADDRESS(fp) ((SCM*)SCM_FRAME_STRUCT (fp))
-
-#define SCM_FRAME_BYTE_CAST(x) ((scm_t_uint8 *) SCM_UNPACK (x))
-#define SCM_FRAME_STACK_CAST(x) ((SCM *) SCM_UNPACK (x))
-
-#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_MV_RETURN_ADDRESS(fp) \
- (SCM_FRAME_STRUCT (fp)->mv_return_address)
-#define SCM_FRAME_SET_MV_RETURN_ADDRESS(fp, mvra) \
- SCM_FRAME_STRUCT (fp)->mv_return_address = (mvra)
-#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_VARIABLE(fp,i) \
- (SCM_FRAME_STRUCT (fp)->stack[i])
-#define SCM_FRAME_PROGRAM(fp) \
- (SCM_FRAME_STRUCT (fp)->program)
-
-\f
-/*
- * RTL frames
- */
-
-/* The frame format for the new RTL programs is almost like that for the
- stack-vm programs. They differ in their handling of MV returns,
- however. For RTL, every call is an MV call: every call has an MVRA.
- Unlike the stack-vm programs, the MVRA for RTL programs is computable
- from the RA -- it's always one word (4 bytes) before the RA.
-
- Until we completely migrate to the RTL VM, we will also write the
- MVRA to the stack.
-
- When an RTL program returns multiple values, it will shuffle them
- down to start contiguously from slot 0, as for a tail call. This
- means that when the caller goes to access them, there are 2 or 3
- empty words between the top of the caller stack and the bottom of the
- values, corresponding to the frame that was just popped.
-*/
-
-#define SCM_FRAME_RTL_RETURN_ADDRESS(fp) \
- ((scm_t_uint32 *) SCM_FRAME_RETURN_ADDRESS (fp))
-#define SCM_FRAME_SET_RTL_RETURN_ADDRESS(fp, ip) \
- SCM_FRAME_SET_RETURN_ADDRESS (fp, (scm_t_uint8 *) (ip))
-
-#define SCM_FRAME_RTL_MV_RETURN_ADDRESS(fp) \
- ((scm_t_uint32 *) SCM_FRAME_MV_RETURN_ADDRESS (fp))
-#define SCM_FRAME_SET_RTL_MV_RETURN_ADDRESS(fp, ip) \
- SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, (scm_t_uint8 *) (ip))
-
-\f
-/*
- * Heap frames
- */
-
-struct scm_frame
-{
- SCM stack_holder;
- SCM *fp;
- SCM *sp;
- scm_t_uint8 *ip;
- scm_t_ptrdiff offset;
-};
-
-#define SCM_VM_FRAME_P(x) (SCM_HAS_TYP7 (x, scm_tc7_frame))
-#define SCM_VM_FRAME_DATA(x) ((struct scm_frame*)SCM_CELL_WORD_1 (x))
-#define SCM_VM_FRAME_STACK_HOLDER(f) SCM_VM_FRAME_DATA(f)->stack_holder
-#define SCM_VM_FRAME_FP(f) SCM_VM_FRAME_DATA(f)->fp
-#define SCM_VM_FRAME_SP(f) SCM_VM_FRAME_DATA(f)->sp
-#define SCM_VM_FRAME_IP(f) SCM_VM_FRAME_DATA(f)->ip
-#define SCM_VM_FRAME_OFFSET(f) SCM_VM_FRAME_DATA(f)->offset
-#define SCM_VALIDATE_VM_FRAME(p,x) SCM_MAKE_VALIDATE (p, x, VM_FRAME_P)
-
-SCM_API SCM scm_c_make_frame (SCM stack_holder, SCM *fp, SCM *sp,
- scm_t_uint8 *ip, scm_t_ptrdiff offset);
-SCM_API SCM scm_frame_p (SCM obj);
-SCM_API SCM scm_frame_procedure (SCM frame);
-SCM_API SCM scm_frame_arguments (SCM frame);
-SCM_API SCM scm_frame_source (SCM frame);
-SCM_API SCM scm_frame_num_locals (SCM frame);
-SCM_API SCM scm_frame_local_ref (SCM frame, SCM index);
-SCM_API SCM scm_frame_local_set_x (SCM frame, SCM index, SCM val);
-SCM_API SCM scm_frame_address (SCM frame);
-SCM_API SCM scm_frame_stack_pointer (SCM frame);
-SCM_API SCM scm_frame_instruction_pointer (SCM frame);
-SCM_API SCM scm_frame_return_address (SCM frame);
-SCM_API SCM scm_frame_mv_return_address (SCM frame);
-SCM_API SCM scm_frame_dynamic_link (SCM frame);
-SCM_API SCM scm_frame_previous (SCM frame);
-
-SCM_INTERNAL void scm_i_frame_print (SCM frame, SCM port,
- scm_print_state *pstate);
-SCM_INTERNAL void scm_init_frames (void);
-
-#endif /* _SCM_FRAMES_H_ */
-
-/*
- Local Variables:
- c-file-style: "gnu"
- End:
-*/
+/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013, 2014 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
+ * as published by the Free Software Foundation; either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef _SCM_FRAMES_H_
+#define _SCM_FRAMES_H_
+
+#include <libguile.h>
+#include "programs.h"
+
+\f
+/* Stack frames
+ ------------
+
+ It's a little confusing, but there are two representations of frames
+ in this file: frame pointers, and Scheme objects wrapping those frame
+ pointers. The former uses the SCM_FRAME macro prefix, the latter
+ SCM_VM_FRAME prefix.
+
+ The confusing thing is that only Scheme frame objects have functions
+ that use them, and they use the lower-case scm_frame prefix.
+
+
+ Stack frame layout
+ ------------------
+
+ /------------------\
+ | Local N-1 | <- sp
+ | ... |
+ | Local 1 |
+ | Local 0 | <- fp = SCM_FRAME_LOCALS_ADDRESS (fp)
+ +==================+
+ | Return address |
+ | Dynamic link | <- fp - 2 = SCM_FRAME_LOWER_ADDRESS (fp)
+ +==================+
+ | | <- fp - 3 = SCM_FRAME_PREVIOUS_SP (fp)
+
+ 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.
+
+ After ensuring that the correct number of arguments have been passed,
+ a function will set the stack pointer to point to the last local
+ slot. This lets a function allocate the temporary space that it
+ needs once in the beginning of the call, instead of pushing and
+ popping the stack pointer during the call's extent.
+
+ When a program returns, it returns its values in the slots starting
+ from local 1, as if the values were arguments to a tail call. We
+ start from 1 instead of 0 for the convenience of the "values" builtin
+ function, which can just leave its arguments in place.
+
+ The callee resets the stack pointer to point to the last value. In
+ this way the caller knows how many values there are: it's the number
+ of words between the stack pointer and the slot at which the caller
+ placed the procedure.
+
+ After checking that the number of values returned is appropriate, the
+ caller shuffles the values around (if needed), and resets the stack
+ pointer back to its original value from before the call. */
+
+
+\f
+
+/* This structure maps to the contents of a VM stack frame. It can
+ alias a frame directly. */
+struct scm_vm_frame
+{
+ 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)
+
+#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])
+
+#define SCM_FRAME_NUM_LOCALS(fp, sp) \
+ ((sp) + 1 - &SCM_FRAME_LOCAL (fp, 0))
+
+\f
+/*
+ * Heap frames
+ */
+
+#ifdef BUILDING_LIBGUILE
+
+struct scm_frame
+{
+ void *stack_holder;
+ scm_t_ptrdiff fp_offset;
+ scm_t_ptrdiff sp_offset;
+ scm_t_uint32 *ip;
+};
+
+enum scm_vm_frame_kind
+ {
+ SCM_VM_FRAME_KIND_VM,
+ SCM_VM_FRAME_KIND_CONT
+ };
+
+#define SCM_VM_FRAME_P(x) (SCM_HAS_TYP7 (x, scm_tc7_frame))
+#define SCM_VM_FRAME_KIND(x) ((enum scm_vm_frame_kind) (SCM_CELL_WORD_0 (x) >> 8))
+#define SCM_VM_FRAME_DATA(x) ((struct scm_frame *)SCM_CELL_WORD_1 (x))
+#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_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 scm_t_ptrdiff scm_i_frame_offset (SCM frame);
+
+/* See notes in frames.c before using this. */
+SCM_INTERNAL SCM scm_c_frame_closure (enum scm_vm_frame_kind kind,
+ const struct scm_frame *frame);
+
+SCM_INTERNAL SCM scm_c_make_frame (enum scm_vm_frame_kind kind,
+ const struct scm_frame *frame);
+
+SCM_INTERNAL int scm_c_frame_previous (enum scm_vm_frame_kind kind,
+ struct scm_frame *frame);
+
+#endif
+
+SCM_API SCM scm_frame_p (SCM obj);
+SCM_API SCM scm_frame_procedure (SCM frame);
+SCM_API SCM scm_frame_call_representation (SCM frame);
+SCM_API SCM scm_frame_arguments (SCM frame);
+SCM_API SCM scm_frame_source (SCM frame);
+SCM_API SCM scm_frame_num_locals (SCM frame);
+SCM_API SCM scm_frame_local_ref (SCM frame, SCM index);
+SCM_API SCM scm_frame_local_set_x (SCM frame, SCM index, SCM val);
+SCM_API SCM scm_frame_address (SCM frame);
+SCM_API SCM scm_frame_stack_pointer (SCM frame);
+SCM_API SCM scm_frame_instruction_pointer (SCM frame);
+SCM_API SCM scm_frame_return_address (SCM frame);
+SCM_API SCM scm_frame_dynamic_link (SCM frame);
+SCM_API SCM scm_frame_previous (SCM frame);
+
+SCM_INTERNAL void scm_i_frame_print (SCM frame, SCM port,
+ scm_print_state *pstate);
+SCM_INTERNAL void scm_init_frames (void);
+
+#endif /* _SCM_FRAMES_H_ */
+
+/*
+ Local Variables:
+ c-file-style: "gnu"
+ End:
+*/
HCoop / bpt / guile.git / blobdiff