From 15812533fce5ae7f2c1d1961c19c8f440c818274 Mon Sep 17 00:00:00 2001
From: Andrew Reynolds <andrew.j.reynolds@gmail.com>
Date: Fri, 6 May 2022 17:06:07 -0500
Subject: [PATCH] Eliminate arithmetic subtyping for (dis)equalities from TPTP
 parser (#8724)

Towards making equality strictly typed / eliminating arithmetic subtyping.
---
 src/parser/tptp/tptp.cpp | 39 +++++++++++++++++++++++++++++++++------
 1 file changed, 33 insertions(+), 6 deletions(-)

diff --git a/src/parser/tptp/tptp.cpp b/src/parser/tptp/tptp.cpp
index d4d0a874f..7da9380e1 100644
--- a/src/parser/tptp/tptp.cpp
+++ b/src/parser/tptp/tptp.cpp
@@ -330,15 +330,37 @@ cvc5::Term Tptp::applyParseOp(ParseOp& p, std::vector<cvc5::Term>& args)
   // Second phase: apply parse op to the arguments
   if (isBuiltinKind)
   {
-    if (!hol() && (kind == cvc5::EQUAL || kind == cvc5::DISTINCT))
+    if (kind == cvc5::EQUAL || kind == cvc5::DISTINCT)
     {
-      // need hol if these operators are applied over function args
-      for (std::vector<cvc5::Term>::iterator i = args.begin(); i != args.end();
-           ++i)
+      std::vector<Sort> sorts;
+      size_t nargs = args.size();
+      for (size_t i = 0; i < nargs; i++)
       {
-        if ((*i).getSort().isFunction())
+        Sort s = args[i].getSort();
+        if (s.isFunction())
         {
-          parseError("Cannot apply equalty to functions unless THF.");
+          // need hol if these operators are applied over function args
+          if (!hol())
+          {
+            parseError("Cannot apply equalty to functions unless THF.");
+          }
+        }
+        sorts.push_back(s);
+      }
+      // TPTP assumes Int/Real subtyping, but the cvc5 API does not
+      for (size_t i = 0; i < nargs; i++)
+      {
+        if (sorts[i].isReal())
+        {
+          // cast all Integer arguments to Real
+          for (size_t j = 0; j < nargs; j++)
+          {
+            if (j != i && sorts[j].isInteger())
+            {
+              args[j] = d_solver->mkTerm(TO_REAL, {args[j]});
+            }
+          }
+          break;
         }
       }
     }
@@ -501,6 +523,11 @@ cvc5::Term Tptp::convertRatToUnsorted(cvc5::Term expr)
   cvc5::Term ret = d_solver->mkTerm(cvc5::APPLY_UF, {d_rtu_op, expr});
   if (d_r_converted.find(expr) == d_r_converted.end()) {
     d_r_converted.insert(expr);
+    if (expr.getSort().isInteger())
+    {
+      // ensure the equality below is between reals
+      expr = d_solver->mkTerm(TO_REAL, {expr});
+    }
     cvc5::Term eq = d_solver->mkTerm(
         cvc5::EQUAL, {expr, d_solver->mkTerm(cvc5::APPLY_UF, {d_utr_op, ret})});
     preemptCommand(new AssertCommand(eq));
-- 
2.30.2