Remove unused is_update argument (#8487)

Affects apply_split in ApplySplit.cpp and build_loop_nest in
ScheduleFunctions.cpp. Fix callers in Func.cpp, too (rfactor).

src/ApplySplit.cpp

@@ -11,7 +11,7 @@ using std::map;
 using std::string;
 using std::vector;
 
-vector<ApplySplitResult> apply_split(const Split &split, bool is_update, const string &prefix,
+vector<ApplySplitResult> apply_split(const Split &split, const string &prefix,
                                      map<string, Expr> &dim_extent_alignment) {
     vector<ApplySplitResult> result;
 

src/ApplySplit.h

@@ -79,7 +79,7 @@ struct ApplySplitResult {
  * defined the values of variables referred by the predicates and substitutions
  * (ordered from innermost to outermost let). */
 std::vector<ApplySplitResult> apply_split(
-    const Split &split, bool is_update, const std::string &prefix,
+    const Split &split, const std::string &prefix,
     std::map<std::string, Expr> &dim_extent_alignment);
 
 /** Compute the loop bounds of the new dimensions resulting from applying the

src/Func.cpp

@@ -659,7 +659,7 @@ bool apply_split(const Split &s, vector<ReductionVariable> &rvars,
 
         rvars.insert(it + 1, {s.outer, 0, simplify((old_extent - 1 + s.factor) / s.factor)});
 
-        vector<ApplySplitResult> splits_result = apply_split(s, true, "", dim_extent_alignment);
+        vector<ApplySplitResult> splits_result = apply_split(s, "", dim_extent_alignment);
         vector<pair<string, Expr>> bounds_let_stmts = compute_loop_bounds_after_split(s, "");
         apply_split_result(bounds_let_stmts, splits_result, predicates, args, values);
 
@@ -694,7 +694,7 @@ bool apply_fuse(const Split &s, vector<ReductionVariable> &rvars,
         iter_outer->extent = extent;
         rvars.erase(iter_inner);
 
-        vector<ApplySplitResult> splits_result = apply_split(s, true, "", dim_extent_alignment);
+        vector<ApplySplitResult> splits_result = apply_split(s, "", dim_extent_alignment);
         vector<pair<string, Expr>> bounds_let_stmts = compute_loop_bounds_after_split(s, "");
         apply_split_result(bounds_let_stmts, splits_result, predicates, args, values);
 
@@ -718,7 +718,7 @@ bool apply_purify(const Split &s, vector<ReductionVariable> &rvars,
                  << ", deleting it from the rvars list\n";
         rvars.erase(iter);
 
-        vector<ApplySplitResult> splits_result = apply_split(s, true, "", dim_extent_alignment);
+        vector<ApplySplitResult> splits_result = apply_split(s, "", dim_extent_alignment);
         vector<pair<string, Expr>> bounds_let_stmts = compute_loop_bounds_after_split(s, "");
         apply_split_result(bounds_let_stmts, splits_result, predicates, args, values);
 
@@ -738,7 +738,7 @@ bool apply_rename(const Split &s, vector<ReductionVariable> &rvars,
         debug(4) << "  Renaming " << iter->var << " into " << s.outer << "\n";
         iter->var = s.outer;
 
-        vector<ApplySplitResult> splits_result = apply_split(s, true, "", dim_extent_alignment);
+        vector<ApplySplitResult> splits_result = apply_split(s, "", dim_extent_alignment);
         vector<pair<string, Expr>> bounds_let_stmts = compute_loop_bounds_after_split(s, "");
         apply_split_result(bounds_let_stmts, splits_result, predicates, args, values);
 

src/ScheduleFunctions.cpp

@@ -174,8 +174,7 @@ Stmt build_loop_nest(
     const string &prefix,
     int start_fuse,
     const Function &func,
-    const Definition &def,
-    bool is_update) {
+    const Definition &def) {
     const auto &dims = func.args();
     const auto &func_s = func.schedule();
     const auto &stage_s = def.schedule();
@@ -220,7 +219,7 @@ Stmt build_loop_nest(
         user_assert(predicated_vars.count(split.old_var) == 0)
             << "Cannot split a loop variable resulting from a split using PredicateLoads or PredicateStores.";
 
-        vector<ApplySplitResult> splits_result = apply_split(split, is_update, prefix, dim_extent_alignment);
+        vector<ApplySplitResult> splits_result = apply_split(split, prefix, dim_extent_alignment);
 
         // To ensure we substitute all indices used in call or provide,
         // we need to substitute all lets in, so we correctly guard x in
@@ -503,7 +502,7 @@ Stmt build_provide_loop_nest(const map<string, Function> &env,
     }
 
     // Default schedule/values if there is no specialization
-    Stmt stmt = build_loop_nest(body, prefix, start_fuse, func, def, is_update);
+    Stmt stmt = build_loop_nest(body, prefix, start_fuse, func, def);
     stmt = inject_placeholder_prefetch(stmt, env, prefix, def.schedule().prefetches());
 
     // Make any specialized copies
@@ -847,7 +846,7 @@ Stmt build_extern_produce(const map<string, Function> &env, Function f, const Ta
 
     Definition f_def_no_pred = f.definition().get_copy();
     f_def_no_pred.predicate() = const_true();
-    return build_loop_nest(check, f.name() + ".s0.", -1, f, f_def_no_pred, false);
+    return build_loop_nest(check, f.name() + ".s0.", -1, f, f_def_no_pred);
 }
 
 // A schedule may include explicit bounds on some dimension. This