aboutsummaryrefslogtreecommitdiffstats
path: root/cfrontend/Ctypes.v
Commit message (Collapse)AuthorAgeFilesLines
* Qualify `Instance` and `Program Instance` as `Global`Xavier Leroy2021-10-031-4/+4
| | | | This avoids a new warning of Coq 8.14.
* Avoid `Global Set Asymmetric Patterns` (#408)Xavier Leroy2021-09-151-0/+2
| | | | | | Instead, add `Set Asymmetric Patterns` to the files that need it, or use `Arguments` to make inductive types work better with symmetric patterns. Closes: #403
* Native support for bit fields (#400)Xavier Leroy2021-08-221-124/+461
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This big PR adds support for bit fields in structs and unions to the verified part of CompCert, namely the CompCert C and Clight languages. The compilation of bit field accesses to normal integer accesses + shifts and masks is done and proved correct as part of the Cshmgen pass. The layout of bit fields in memory is done by the functions in module Ctypes. It follows the ELF ABI layout algorithm. As a bonus, basic soundness properties of the layout are shown, such as "two different bit fields do not overlap" or "a bit field and a regular field do not overlap". All this replaces the previous emulation of bit fields by source-to-source rewriting in the unverified front-end of CompCert (module cparse/Bitfield.ml). This emulation was prone to errors (see nonstandard layout instead. The core idea for the PR is that expressions in l-value position denote not just a block, a byte offset and a type, but also a bitfield designator saying whether all the bits of the type are accessed (designator Full) or only some of its bits (designator Bits). Designators of the Bits kind appear when the l-value is a bit field access; the bit width and bit offset in Bits are computed by the functions in Ctypes that implement the layout algorithm. Consequently, both in the semantics of CompCert C and Clight and in the SimplExpr, SimplLocals and Cshmgen compilation passes, pairs of a type and a bitfield designator are used in a number of places where a single type was used before. The introduction of bit fields has a big impact on static initialization (module cfrontend/Initializers.v), which had to be rewritten in large part, along with its soundness proof (cfrontend/Initializersproof.v). Both static initialization and run-time manipulation of bit fields are tested in test/abi using differential testing against GCC and randomly-generated structs. This work exposed subtle interactions between bit fields and the volatile modifier. Currently, the volatile modifier is ignored when accessing a bit field (and a warning is printed at compile-time), just like it is ignored when accessing a struct or union as a r-value. Currently, the natural alignment of bit fields and their storage units cannot be modified with the aligned attribute. _Alignas on bit fields is rejected as per C11, and the packed modifier cannot be applied to a struct containing bit fields.
* Add Ctypes.link_match_program_genXavier Leroy2021-08-221-0/+52
| | | | | A more general version of the link_match_program linking theorem. It supports match_fundef relations parameterized by the source compilation unit.
* Use the LGPL instead of the GPL for dual-licensed filesXavier Leroy2021-05-081-4/+5
| | | | | | The GPL makes sense for whole applications, but the dual-licensed Coq and OCaml files are more like libraries to be combined with other code, so the LGPL is more appropriate.
* Replace `omega` tactic with `lia`Xavier Leroy2020-12-291-19/+22
| | | | | | | | | | | Since Coq 8.12, `omega` is flagged as deprecated and scheduled for removal. Also replace CompCert's homemade tactics `omegaContradiction`, `xomega`, and `xomegaContradiction` with `lia` and `extlia`. Turn back on the deprecation warning for uses of `omega`. Make the proof of `Ctypes.sizeof_pos` more robust to variations in `lia`.
* Changed cc_varargs to an option typeBernhard Schommer2020-12-251-0/+1
| | | | | | Instead of being a simple boolean we now use an option type to record the number of fixed (non-vararg) arguments. Hence, `None` means not vararg, and `Some n` means `n` fixed arguments followed with varargs.
* Refine the type of function results in AST.signatureXavier Leroy2020-02-211-3/+16
| | | | | | | | | | Before it was "option typ". Now it is a proper inductive type that can also express small integer types (8/16-bit unsigned/signed integers). One benefit is that external functions get more precise types that control better their return values. As a consequence, the CompCert C type preservation property now holds unconditionally, without extra typing hypotheses on external functions.
* Use `Program Instance` instead of `Instance` + refine mode (#261)Maxime Dénès2018-12-271-23/+33
| | | | | | | | | | | | | CompCert currently uses `Instance` in so-called "refine" mode, where Coq drops automatically in proof mode if some members of the instance are missing. This mode is soon going to be turned off by default, see https://github.com/coq/coq/pull/9270. In order to make CompCert robust against this change, this commit replaces those occurrences of `Instance` that use "refine" mode with `Program Instance`.
* Remove coq warnings (#28)Bernhard Schommer2017-09-221-28/+28
| | | | Replace deprecated functions and theorems from the Coq standard library (version 8.6) by their non-deprecated counterparts.
* An hypothesis has changed name.Maxime Dénès2017-01-091-1/+1
| | | | Not sure why, but it would be safer not to rely on automatic naming.
* The subst tactic has become more powerful.Maxime Dénès2017-01-091-1/+1
|
* Support for 64-bit architectures: generic supportXavier Leroy2016-10-011-22/+28
| | | | | | | | | | | - Introduce Archi.ptr64 parameter. - Define module Ptrofs of integers as wide as a pointer (64 if Archi.ptr64, 32 otherwise). - Use Ptrofs.int as the offset type for Vptr values and anywhere pointer offsets are manipulated. - Modify Val operations that handle pointers (e.g. Val.add, Val.sub, Val.cmpu) so that in 64-bit pointer mode it is the "long" operation (e.g. Val.addl, Val.subl, Val.cmplu) that handles pointers. - Update the memory model accordingly. - Modify C operations that handle pointers (e.g. addition, subtraction, comparisons) accordingly. - Make it possible to turn off the splitting of 64-bit integers into pairs of 32-bit integers. - Update the compiler front-end and back-end accordingly.
* Define linking for Csyntax and Clight programs.Xavier Leroy2016-03-061-23/+506
| | | | Also: factor out the type "program" between Csyntax and Clight, putting it in Ctypes.
* Updated PR by removing whitespaces. Bug 17450.Bernhard Schommer2015-10-201-58/+58
|
* Ctypes.composite_of_def: make sure it computes within Coq.Xavier Leroy2015-09-181-3/+3
| | | | (Suggested by A. Appel.)
* Define a nonnegative integer "rank" for types to support structural ↵Xavier Leroy2015-01-101-18/+116
| | | | induction over composite types.
* Represent struct and union types by name instead of by structure.Xavier Leroy2014-12-221-331/+552
|
* Merge of "newspilling" branch:xleroy2014-07-231-9/+12
| | | | | | | | | | | | | | | - Support single-precision floats as first-class values - Introduce chunks Many32, Many64 and types Tany32, Tany64 to support saving and restoring registers without knowing the exact types (int/single/float) of their contents, just their sizes. - Memory model: generalize the opaque encoding of pointers to apply to any value, not just pointers, if chunks Many32/Many64 are selected. - More properties of FP arithmetic proved. git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2537 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Clean-up pass on C types:xleroy2014-04-231-4/+41
| | | | | | | | | | | | | - Ctypes: add useful functions on attributes; remove attrs in typeconv (because attributes are meaningless on r-values) - C2C: fixed missing or redundant Evalof - Cop: ignore attributes in ptr + int and ptr - int (meaningless on r-values); add sanity check between typeconv/classify_binarith and the C99 standard. - cparser: fixed several cases where incorrect type annotations were put on expressions. git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2457 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Introduce and use the platform-specific Archi module giving:xleroy2014-01-031-7/+12
| | | | | | | | | | - endianness - alignment constraints for 8-byte types (which is 4 for x86 ABI and 8 for other ABIs) - NaN handling options (superceding the Nan module, removed). git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2402 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Ctypes.sizeof ty = 0 for empty types ty (zero-sized array, empty struct/union).xleroy2013-12-301-18/+15
| | | | | | | __builtin_memcpy_aligned now supports the case sz = 0. git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2392 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Simpler, more robust emulation of calls to variadic functions:xleroy2013-12-281-13/+23
| | | | | | | | | | | | | | - C function types and Cminor signatures annotated by calling conventions. esp. vararg / not vararg - Cshmgen: generate correct code for function call where there are more arguments than listed in the function prototype. This is still undefined behavior according to the formal semantics, but correct code is generated. - C2C, */PrintAsm.ml: remove "printf$iif" hack. - powerpc/, checklink/: don't generate stubs for variadic functions. git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2386 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Revised treatment of _Alignas, for better compatibility with GCC and Clang, ↵xleroy2013-11-061-52/+121
| | | | | | and to avoid wasting global variable space by inflating their sizeof needlessly. git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2362 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Merge of the "alignas" branch.xleroy2013-10-051-85/+146
| | | | git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2342 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Merge of the float32 branch: xleroy2013-05-191-0/+2
| | | | | | | | - added RTL type "Tsingle" - ABI-compatible passing of single-precision floats on ARM and x86 git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2260 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Big merge of the newregalloc-int64 branch. Lots of changes in two directions:xleroy2013-04-201-3/+10
| | | | | | | | | 1- new register allocator (+ live range splitting, spilling&reloading, etc) based on a posteriori validation using the Rideau-Leroy algorithm 2- support for 64-bit integer arithmetic (type "long long"). git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2200 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
* Make Clight independent of CompCert C.xleroy2012-10-081-0/+546
Common parts are factored out in cfrontend/Ctypes.v and cfrontend/Cop.v git-svn-id: https://yquem.inria.fr/compcert/svn/compcert/trunk@2060 fca1b0fc-160b-0410-b1d3-a4f43f01ea2e
generated by cgit (git 2.34.1) at 2024-05-20 00:14:34 +0000