From 783288d052bbcf75e250dff5018443d109c6101c Mon Sep 17 00:00:00 2001 From: xleroy Date: Wed, 23 Jul 2014 13:14:02 +0000 Subject: Merge the various $(ARCH)/$(VARIANT)/xxx.v files into $(ARCH)/xxx.v. The only platform where we have two variants is ARM, and it's easier to share the callling convention code between the two than to maintain both variants separately. git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2540 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e --- ia32/Stacklayout.v | 130 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 130 insertions(+) create mode 100644 ia32/Stacklayout.v (limited to 'ia32/Stacklayout.v') diff --git a/ia32/Stacklayout.v b/ia32/Stacklayout.v new file mode 100644 index 0000000..f9d1daf --- /dev/null +++ b/ia32/Stacklayout.v @@ -0,0 +1,130 @@ +(* *********************************************************************) +(* *) +(* The Compcert verified compiler *) +(* *) +(* Xavier Leroy, INRIA Paris-Rocquencourt *) +(* *) +(* 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 Bounds. + +(** 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 +- Saved values of integer callee-save registers used by the function. +- Saved values of float callee-save registers used by the function. +- Local stack slots. +- Space for the stack-allocated data declared in Cminor +- Return address. + +The [frame_env] compilation environment records the positions of +the boundaries between these areas of the activation record. +*) + +Definition fe_ofs_arg := 0. + +Record frame_env : Type := mk_frame_env { + fe_size: Z; + fe_ofs_link: Z; + fe_ofs_retaddr: Z; + fe_ofs_local: Z; + fe_ofs_int_callee_save: Z; + fe_num_int_callee_save: Z; + fe_ofs_float_callee_save: Z; + fe_num_float_callee_save: Z; + fe_stack_data: Z +}. + +(** Computation of the frame environment from the bounds of the current + function. *) + +Definition make_env (b: bounds) := + let olink := 4 * b.(bound_outgoing) in (* back link *) + let oics := olink + 4 in (* integer callee-saves *) + let ofcs := align (oics + 4 * b.(bound_int_callee_save)) 8 in (* float callee-saves *) + let ol := ofcs + 8 * b.(bound_float_callee_save) in (* locals *) + let ostkdata := align (ol + 4 * b.(bound_local)) 8 in (* stack data *) + let oretaddr := align (ostkdata + b.(bound_stack_data)) 4 in (* return address *) + let sz := oretaddr + 4 in (* total size *) + mk_frame_env sz olink oretaddr + ol + oics b.(bound_int_callee_save) + ofcs b.(bound_float_callee_save) + ostkdata. + +(** Separation property *) + +Remark frame_env_separated: + forall b, + let fe := make_env b in + 0 <= fe_ofs_arg + /\ fe_ofs_arg + 4 * b.(bound_outgoing) <= fe.(fe_ofs_link) + /\ fe.(fe_ofs_link) + 4 <= fe.(fe_ofs_int_callee_save) + /\ fe.(fe_ofs_int_callee_save) + 4 * b.(bound_int_callee_save) <= fe.(fe_ofs_float_callee_save) + /\ fe.(fe_ofs_float_callee_save) + 8 * b.(bound_float_callee_save) <= fe.(fe_ofs_local) + /\ fe.(fe_ofs_local) + 4 * b.(bound_local) <= fe.(fe_stack_data) + /\ fe.(fe_stack_data) + b.(bound_stack_data) <= fe.(fe_ofs_retaddr) + /\ fe.(fe_ofs_retaddr) + 4 <= fe.(fe_size). +Proof. + intros. + generalize (align_le (fe.(fe_ofs_int_callee_save) + 4 * b.(bound_int_callee_save)) 8 (refl_equal _)). + generalize (align_le (fe.(fe_ofs_local) + 4 * b.(bound_local)) 8 (refl_equal _)). + generalize (align_le (fe.(fe_stack_data) + b.(bound_stack_data)) 4 (refl_equal _)). + unfold fe, make_env, fe_size, fe_ofs_link, fe_ofs_retaddr, + fe_ofs_local, fe_ofs_int_callee_save, fe_num_int_callee_save, + fe_ofs_float_callee_save, fe_num_float_callee_save, + fe_stack_data, fe_ofs_arg. + intros. + generalize (bound_local_pos b); intro; + generalize (bound_int_callee_save_pos b); intro; + generalize (bound_float_callee_save_pos b); intro; + generalize (bound_outgoing_pos b); intro; + generalize (bound_stack_data_pos b); intro. + omega. +Qed. + +(** Alignment property *) + +Remark frame_env_aligned: + forall b, + let fe := make_env b in + (4 | fe.(fe_ofs_link)) + /\ (4 | fe.(fe_ofs_int_callee_save)) + /\ (8 | fe.(fe_ofs_float_callee_save)) + /\ (8 | fe.(fe_ofs_local)) + /\ (8 | fe.(fe_stack_data)) + /\ (4 | fe.(fe_ofs_retaddr)) + /\ (4 | fe.(fe_size)). +Proof. + intros. + unfold fe, make_env, fe_size, fe_ofs_link, fe_ofs_retaddr, + fe_ofs_local, fe_ofs_int_callee_save, + fe_num_int_callee_save, + fe_ofs_float_callee_save, fe_num_float_callee_save, + fe_stack_data. + set (x1 := 4 * bound_outgoing b). + assert (4 | x1). unfold x1; exists (bound_outgoing b); ring. + set (x2 := x1 + 4). + assert (4 | x2). unfold x2; apply Zdivide_plus_r; auto. exists 1; auto. + set (x3 := x2 + 4 * bound_int_callee_save b). + set (x4 := align x3 8). + assert (8 | x4). unfold x4. apply align_divides. omega. + set (x5 := x4 + 8 * bound_float_callee_save b). + assert (8 | x5). unfold x5; apply Zdivide_plus_r; auto. exists (bound_float_callee_save b); ring. + set (x6 := align (x5 + 4 * bound_local b) 8). + assert (8 | x6). unfold x6; apply align_divides; omega. + set (x7 := align (x6 + bound_stack_data b) 4). + assert (4 | x7). unfold x7; apply align_divides; omega. + set (x8 := x7 + 4). + assert (4 | x8). unfold x8; apply Zdivide_plus_r; auto. exists 1; auto. + tauto. +Qed. + -- cgit v1.2.3