src/HOL/SMT.thy
changeset 36898 8e55aa1306c5
child 36899 bcd6fce5bf06
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/HOL/SMT.thy	Wed May 12 23:54:02 2010 +0200
@@ -0,0 +1,306 @@
+(*  Title:      HOL/SMT.thy
+    Author:     Sascha Boehme, TU Muenchen
+*)
+
+header {* Bindings to Satisfiability Modulo Theories (SMT) solvers *}
+
+theory SMT
+imports List
+uses
+  "~~/src/Tools/cache_io.ML"
+  ("Tools/SMT/smt_additional_facts.ML")
+  ("Tools/SMT/smt_monomorph.ML")
+  ("Tools/SMT/smt_normalize.ML")
+  ("Tools/SMT/smt_translate.ML")
+  ("Tools/SMT/smt_solver.ML")
+  ("Tools/SMT/smtlib_interface.ML")
+  ("Tools/SMT/z3_proof_parser.ML")
+  ("Tools/SMT/z3_proof_tools.ML")
+  ("Tools/SMT/z3_proof_literals.ML")
+  ("Tools/SMT/z3_proof_reconstruction.ML")
+  ("Tools/SMT/z3_model.ML")
+  ("Tools/SMT/z3_interface.ML")
+  ("Tools/SMT/z3_solver.ML")
+  ("Tools/SMT/cvc3_solver.ML")
+  ("Tools/SMT/yices_solver.ML")
+begin
+
+
+
+section {* Triggers for quantifier instantiation *}
+
+text {*
+Some SMT solvers support triggers for quantifier instantiation.
+Each trigger consists of one ore more patterns.  A pattern may either
+be a list of positive subterms (the first being tagged by "pat" and
+the consecutive subterms tagged by "andpat"), or a list of negative
+subterms (the first being tagged by "nopat" and the consecutive
+subterms tagged by "andpat").
+*}
+
+datatype pattern = Pattern
+
+definition pat :: "'a \<Rightarrow> pattern"
+where "pat _ = Pattern"
+
+definition nopat :: "'a \<Rightarrow> pattern"
+where "nopat _ = Pattern"
+
+definition andpat :: "pattern \<Rightarrow> 'a \<Rightarrow> pattern" (infixl "andpat" 60)
+where "_ andpat _ = Pattern"
+
+definition trigger :: "pattern list \<Rightarrow> bool \<Rightarrow> bool"
+where "trigger _ P = P"
+
+
+
+section {* Higher-order encoding *}
+
+text {*
+Application is made explicit for constants occurring with varying
+numbers of arguments.  This is achieved by the introduction of the
+following constant.
+*}
+
+definition "apply" where "apply f x = f x"
+
+text {*
+Some solvers support a theory of arrays which can be used to encode
+higher-order functions.  The following set of lemmas specifies the
+properties of such (extensional) arrays.
+*}
+
+lemmas array_rules = ext fun_upd_apply fun_upd_same fun_upd_other
+  fun_upd_upd
+
+
+
+section {* First-order logic *}
+
+text {*
+Some SMT solvers require a strict separation between formulas and
+terms.  When translating higher-order into first-order problems,
+all uninterpreted constants (those not builtin in the target solver)
+are treated as function symbols in the first-order sense.  Their
+occurrences as head symbols in atoms (i.e., as predicate symbols) is
+turned into terms by equating such atoms with @{term True} using the
+following term-level equation symbol.
+*}
+
+definition term_eq :: "bool \<Rightarrow> bool \<Rightarrow> bool" (infix "term'_eq" 50)
+  where "(x term_eq y) = (x = y)"
+
+
+
+section {* Setup *}
+
+use "Tools/SMT/smt_monomorph.ML"
+use "Tools/SMT/smt_normalize.ML"
+use "Tools/SMT/smt_translate.ML"
+use "Tools/SMT/smt_solver.ML"
+use "Tools/SMT/smtlib_interface.ML"
+use "Tools/SMT/z3_interface.ML"
+use "Tools/SMT/z3_proof_parser.ML"
+use "Tools/SMT/z3_proof_tools.ML"
+use "Tools/SMT/z3_proof_literals.ML"
+use "Tools/SMT/z3_proof_reconstruction.ML"
+use "Tools/SMT/z3_model.ML"
+use "Tools/SMT/z3_solver.ML"
+use "Tools/SMT/cvc3_solver.ML"
+use "Tools/SMT/yices_solver.ML"
+
+setup {*
+  SMT_Solver.setup #>
+  Z3_Proof_Reconstruction.setup #>
+  Z3_Solver.setup #>
+  CVC3_Solver.setup #>
+  Yices_Solver.setup
+*}
+
+
+
+section {* Configuration *}
+
+text {*
+The current configuration can be printed by the following command
+(which shows the values of most options):
+*}
+
+smt_status
+
+
+
+subsection {* General configuration options *}
+
+text {*
+The option @{text smt_solver} can be used to change the target SMT
+solver.  The possible values are @{text cvc3}, @{text yices}, and
+@{text z3}.  It is advisable to locally install the selected solver,
+although this is not necessary for @{text cvc3} and @{text z3}, which
+can also be used over an Internet-based service.
+
+When using local SMT solvers, the path to their binaries should be
+declared by setting the following environment variables:
+@{text CVC3_SOLVER}, @{text YICES_SOLVER}, and @{text Z3_SOLVER}.
+*}
+
+declare [[ smt_solver = z3 ]]
+
+text {*
+Since SMT solvers are potentially non-terminating, there is a timeout
+(given in seconds) to restrict their runtime.  A value greater than
+120 (seconds) is in most cases not advisable.
+*}
+
+declare [[ smt_timeout = 20 ]]
+
+
+
+subsection {* Certificates *}
+
+text {*
+By setting the option @{text smt_certificates} to the name of a file,
+all following applications of an SMT solver a cached in that file.
+Any further application of the same SMT solver (using the very same
+configuration) re-uses the cached certificate instead of invoking the
+solver.  An empty string disables caching certificates.
+
+The filename should be given as an explicit path.  It is good
+practice to use the name of the current theory (with ending
+@{text ".certs"} instead of @{text ".thy"}) as the certificates file.
+*}
+
+declare [[ smt_certificates = "" ]]
+
+text {*
+The option @{text smt_fixed} controls whether only stored
+certificates are should be used or invocation of an SMT solver is
+allowed.  When set to @{text true}, no SMT solver will ever be
+invoked and only the existing certificates found in the configured
+cache are used;  when set to @{text false} and there is no cached
+certificate for some proposition, then the configured SMT solver is
+invoked.
+*}
+
+declare [[ smt_fixed = false ]]
+
+
+
+subsection {* Tracing *}
+
+text {*
+For tracing the generated problem file given to the SMT solver as
+well as the returned result of the solver, the option
+@{text smt_trace} should be set to @{text true}.
+*}
+
+declare [[ smt_trace = false ]]
+
+
+
+subsection {* Z3-specific options *}
+
+text {*
+Z3 is the only SMT solver whose proofs are checked (or reconstructed)
+in Isabelle (all other solvers are implemented as oracles).  Enabling
+or disabling proof reconstruction for Z3 is controlled by the option
+@{text z3_proofs}. 
+*}
+
+declare [[ z3_proofs = true ]]
+
+text {*
+From the set of assumptions given to Z3, those assumptions used in
+the proof are traced when the option @{text z3_trace_assms} is set to
+@{term true}.
+*}
+
+declare [[ z3_trace_assms = false ]]
+
+text {*
+Z3 provides several commandline options to tweak its behaviour.  They
+can be configured by writing them literally as value for the option
+@{text z3_options}.
+*}
+
+declare [[ z3_options = "" ]]
+
+
+
+section {* Schematic rules for Z3 proof reconstruction *}
+
+text {*
+Several prof rules of Z3 are not very well documented.  There are two
+lemma groups which can turn failing Z3 proof reconstruction attempts
+into succeeding ones: the facts in @{text z3_rule} are tried prior to
+any implemented reconstruction procedure for all uncertain Z3 proof
+rules;  the facts in @{text z3_simp} are only fed to invocations of
+the simplifier when reconstructing theory-specific proof steps.
+*}
+
+lemmas [z3_rule] =
+  refl eq_commute conj_commute disj_commute simp_thms nnf_simps
+  ring_distribs field_simps times_divide_eq_right times_divide_eq_left
+  if_True if_False not_not
+
+lemma [z3_rule]:
+  "(P \<longrightarrow> Q) = (Q \<or> \<not>P)"
+  "(\<not>P \<longrightarrow> Q) = (P \<or> Q)"
+  "(\<not>P \<longrightarrow> Q) = (Q \<or> P)"
+  by auto
+
+lemma [z3_rule]:
+  "((P = Q) \<longrightarrow> R) = (R | (Q = (\<not>P)))"
+  by auto
+
+lemma [z3_rule]:
+  "((\<not>P) = P) = False"
+  "(P = (\<not>P)) = False"
+  "(P \<noteq> Q) = (Q = (\<not>P))"
+  "(P = Q) = ((\<not>P \<or> Q) \<and> (P \<or> \<not>Q))"
+  "(P \<noteq> Q) = ((\<not>P \<or> \<not>Q) \<and> (P \<or> Q))"
+  by auto
+
+lemma [z3_rule]:
+  "(if P then P else \<not>P) = True"
+  "(if \<not>P then \<not>P else P) = True"
+  "(if P then True else False) = P"
+  "(if P then False else True) = (\<not>P)"
+  "(if \<not>P then x else y) = (if P then y else x)"
+  by auto
+
+lemma [z3_rule]:
+  "P = Q \<or> P \<or> Q"
+  "P = Q \<or> \<not>P \<or> \<not>Q"
+  "(\<not>P) = Q \<or> \<not>P \<or> Q"
+  "(\<not>P) = Q \<or> P \<or> \<not>Q"
+  "P = (\<not>Q) \<or> \<not>P \<or> Q"
+  "P = (\<not>Q) \<or> P \<or> \<not>Q"
+  "P \<noteq> Q \<or> P \<or> \<not>Q"
+  "P \<noteq> Q \<or> \<not>P \<or> Q"
+  "P \<noteq> (\<not>Q) \<or> P \<or> Q"
+  "(\<not>P) \<noteq> Q \<or> P \<or> Q"
+  "P \<or> Q \<or> P \<noteq> (\<not>Q)"
+  "P \<or> Q \<or> (\<not>P) \<noteq> Q"
+  "P \<or> \<not>Q \<or> P \<noteq> Q"
+  "\<not>P \<or> Q \<or> P \<noteq> Q"
+  by auto
+
+lemma [z3_rule]:
+  "0 + (x::int) = x"
+  "x + 0 = x"
+  "0 * x = 0"
+  "1 * x = x"
+  "x + y = y + x"
+  by auto
+
+lemma [z3_rule]:
+  "0 + (x::real) = x"
+  "x + 0 = x"
+  "0 * x = 0"
+  "1 * x = x"
+  "x + y = y + x"
+  by auto
+
+
+end