From 7cdd676d002e33015b496f609538a9e86d77c543 Mon Sep 17 00:00:00 2001 From: Xavier Leroy Date: Thu, 8 Aug 2019 11:18:38 +0200 Subject: AArch64 port This commit adds a back-end for the AArch64 architecture, namely ARMv8 in 64-bit mode. --- aarch64/Stacklayout.v | 140 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 140 insertions(+) create mode 100644 aarch64/Stacklayout.v (limited to 'aarch64/Stacklayout.v') diff --git a/aarch64/Stacklayout.v b/aarch64/Stacklayout.v new file mode 100644 index 00000000..86ba9f45 --- /dev/null +++ b/aarch64/Stacklayout.v @@ -0,0 +1,140 @@ +(* *********************************************************************) +(* *) +(* The Compcert verified compiler *) +(* *) +(* Xavier Leroy, Collège de France and INRIA Paris *) +(* *) +(* Copyright Institut National de Recherche en Informatique et en *) +(* Automatique. All rights reserved. This file is distributed *) +(* under the terms of the INRIA Non-Commercial License Agreement. *) +(* *) +(* *********************************************************************) + +(** Machine- and ABI-dependent layout information for activation records. *) + +Require Import Coqlib. +Require Import AST Memory Separation. +Require Import Bounds. + +Local Open Scope sep_scope. + +(** The general shape of activation records is as follows, + from bottom (lowest offsets) to top: +- Space for outgoing arguments to function calls. +- Back link to parent frame +- Return address +- Saved values of callee-save registers used by the function. +- Local stack slots. +- Space for the stack-allocated data declared in Cminor. + +The stack pointer is kept 16-aligned. +*) + +Definition fe_ofs_arg := 0. + +Definition make_env (b: bounds) : frame_env := + let olink := align (4 * b.(bound_outgoing)) 8 in (* back link *) + let oretaddr := olink + 8 in (* return address *) + let ocs := oretaddr + 8 in (* callee-saves *) + let ol := align (size_callee_save_area b ocs) 8 in (* locals *) + let ostkdata := align (ol + 4 * b.(bound_local)) 8 in (* stack data *) + let sz := align (ostkdata + b.(bound_stack_data)) 16 in + {| fe_size := sz; + fe_ofs_link := olink; + fe_ofs_retaddr := oretaddr; + fe_ofs_local := ol; + fe_ofs_callee_save := ocs; + fe_stack_data := ostkdata; + fe_used_callee_save := b.(used_callee_save) |}. + +Lemma frame_env_separated: + forall b sp m P, + let fe := make_env b in + m |= range sp 0 (fe_stack_data fe) ** range sp (fe_stack_data fe + bound_stack_data b) (fe_size fe) ** P -> + m |= range sp (fe_ofs_local fe) (fe_ofs_local fe + 4 * bound_local b) + ** range sp fe_ofs_arg (fe_ofs_arg + 4 * bound_outgoing b) + ** range sp (fe_ofs_link fe) (fe_ofs_link fe + size_chunk Mptr) + ** range sp (fe_ofs_retaddr fe) (fe_ofs_retaddr fe + size_chunk Mptr) + ** range sp (fe_ofs_callee_save fe) (size_callee_save_area b (fe_ofs_callee_save fe)) + ** P. +Proof. +Local Opaque Z.add Z.mul sepconj range. + intros; simpl. + set (olink := align (4 * b.(bound_outgoing)) 8). + set (oretaddr := olink + 8). + set (ocs := oretaddr + 8). + set (ol := align (size_callee_save_area b ocs) 8). + set (ostkdata := align (ol + 4 * b.(bound_local)) 8). + change (size_chunk Mptr) with 8. + generalize b.(bound_local_pos) b.(bound_outgoing_pos) b.(bound_stack_data_pos); intros. + assert (0 <= 4 * b.(bound_outgoing)) by omega. + assert (4 * b.(bound_outgoing) <= olink) by (apply align_le; omega). + assert (olink + 8 <= oretaddr) by (unfold oretaddr; omega). + assert (oretaddr + 8 <= ocs) by (unfold ocs; omega). + assert (ocs <= size_callee_save_area b ocs) by (apply size_callee_save_area_incr). + assert (size_callee_save_area b ocs <= ol) by (apply align_le; omega). + assert (ol + 4 * b.(bound_local) <= ostkdata) by (apply align_le; omega). +(* Reorder as: + outgoing + back link + retaddr + callee-save + local *) + rewrite sep_swap12. + rewrite sep_swap23. + rewrite sep_swap34. + rewrite sep_swap45. +(* Apply range_split and range_split2 repeatedly *) + unfold fe_ofs_arg. + apply range_split_2. fold olink; omega. omega. + apply range_split. omega. + apply range_split. omega. + apply range_split_2. fold ol. omega. omega. + apply range_drop_right with ostkdata. omega. + eapply sep_drop2. eexact H. +Qed. + +Lemma frame_env_range: + forall b, + let fe := make_env b in + 0 <= fe_stack_data fe /\ fe_stack_data fe + bound_stack_data b <= fe_size fe. +Proof. + intros; simpl. + set (olink := align (4 * b.(bound_outgoing)) 8). + set (oretaddr := olink + 8). + set (ocs := oretaddr + 8). + set (ol := align (size_callee_save_area b ocs) 8). + set (ostkdata := align (ol + 4 * b.(bound_local)) 8). + generalize b.(bound_local_pos) b.(bound_outgoing_pos) b.(bound_stack_data_pos); intros. + assert (0 <= 4 * b.(bound_outgoing)) by omega. + assert (4 * b.(bound_outgoing) <= olink) by (apply align_le; omega). + assert (olink + 8 <= oretaddr) by (unfold oretaddr; omega). + assert (oretaddr + 8 <= ocs) by (unfold ocs; omega). + assert (ocs <= size_callee_save_area b ocs) by (apply size_callee_save_area_incr). + assert (size_callee_save_area b ocs <= ol) by (apply align_le; omega). + assert (ol + 4 * b.(bound_local) <= ostkdata) by (apply align_le; omega). + split. omega. apply align_le. omega. +Qed. + +Lemma frame_env_aligned: + forall b, + let fe := make_env b in + (8 | fe_ofs_arg) + /\ (8 | fe_ofs_local fe) + /\ (8 | fe_stack_data fe) + /\ (align_chunk Mptr | fe_ofs_link fe) + /\ (align_chunk Mptr | fe_ofs_retaddr fe). +Proof. + intros; simpl. + set (olink := align (4 * b.(bound_outgoing)) 8). + set (oretaddr := olink + 8). + set (ocs := oretaddr + 8). + set (ol := align (size_callee_save_area b ocs) 8). + set (ostkdata := align (ol + 4 * b.(bound_local)) 8). + change (align_chunk Mptr) with 8. + split. apply Z.divide_0_r. + split. apply align_divides; omega. + split. apply align_divides; omega. + split. apply align_divides; omega. + apply Z.divide_add_r. apply align_divides; omega. apply Z.divide_refl. +Qed. -- cgit