From 413daa2aea95deca326aa44a7aadde92782d2c41 Mon Sep 17 00:00:00 2001
From: Mikhail Kocharmin <xnpster@yandex.ru>
Date: Thu, 31 Oct 2024 00:03:32 +0300
Subject: [PATCH] replace_dist_arrays_in_io: insert only necessary copy
 statements

---
 .../replace_dist_arrays_in_io.cpp             | 97 +++++++++++++++----
 1 file changed, 80 insertions(+), 17 deletions(-)

diff --git a/sapfor/experts/Sapfor_2017/_src/Transformations/replace_dist_arrays_in_io.cpp b/sapfor/experts/Sapfor_2017/_src/Transformations/replace_dist_arrays_in_io.cpp
index bc4b9b8..da6cfaa 100644
--- a/sapfor/experts/Sapfor_2017/_src/Transformations/replace_dist_arrays_in_io.cpp
+++ b/sapfor/experts/Sapfor_2017/_src/Transformations/replace_dist_arrays_in_io.cpp
@@ -126,16 +126,70 @@ static void populateDistributedIoArrays(map<DIST::Array*, set<SgStatement*>>& ar
     __spf_print(DEBUG_TRACE, "[replace]\n");
 }
 
-static void replaceArrayRec(SgSymbol* arr, SgSymbol* replace_by, SgExpression* exp)
+static void replaceArrayRec(SgSymbol* arr, SgSymbol* replace_by, SgExpression* exp, bool& has_read, bool& has_write, bool from_read, bool from_write)
 {
     if (!exp)
         return;
 
     if (exp->symbol() && strcmp(exp->symbol()->identifier(), arr->identifier()) == 0)
+    {
+        has_read |= from_read;
+        has_write |= from_write;
         exp->setSymbol(replace_by);
+    }
 
-    replaceArrayRec(arr, replace_by, exp->lhs());
-    replaceArrayRec(arr, replace_by, exp->rhs());
+    switch (exp->variant())
+    {
+        case FUNC_CALL:
+        {
+            replaceArrayRec(arr, replace_by, exp->rhs(), has_read, has_write, true, false);
+            replaceArrayRec(arr, replace_by, exp->lhs(), has_read, has_write, true, true);
+            break;
+        }
+        case EXPR_LIST:
+        {
+            replaceArrayRec(arr, replace_by, exp->lhs(), has_read, has_write, from_read, from_write);
+            replaceArrayRec(arr, replace_by, exp->rhs(), has_read, has_write, from_read, from_write);
+            break;
+        }
+        default:
+        {
+            replaceArrayRec(arr, replace_by, exp->lhs(), has_read, has_write, true, false);
+            replaceArrayRec(arr, replace_by, exp->rhs(), has_read, has_write, true, false);
+            break;
+        }
+    }
+}
+
+static void replaceArrayRec(SgSymbol* arr, SgSymbol* replace_by, SgStatement* st, bool& has_read, bool& has_write)
+{
+    if (!st)
+        return;
+
+    switch (st->variant())
+    {
+        case ASSIGN_STAT:
+        case READ_STAT:
+        {
+            replaceArrayRec(arr, replace_by, st->expr(0), has_read, has_write, false, true);
+            replaceArrayRec(arr, replace_by, st->expr(1), has_read, has_write, true, false);
+            break;
+        }
+        case PROC_STAT:
+        case FUNC_STAT:
+        {
+            replaceArrayRec(arr, replace_by, st->expr(0), has_read, has_write, true, false);
+            replaceArrayRec(arr, replace_by, st->expr(1), has_read, has_write, true, true);
+            break;
+        }
+        default:
+        {
+            for (int i = 0; i < 3; i++)
+                replaceArrayRec(arr, replace_by, st->expr(i), has_read, has_write, true, false);
+
+            break;
+        }
+    }
 }
 
 static void copyArrayBetweenStatements(SgSymbol* replace_symb, SgSymbol* replace_by, SgStatement* start, SgStatement* last)
@@ -144,24 +198,33 @@ static void copyArrayBetweenStatements(SgSymbol* replace_symb, SgSymbol* replace
         start = start->lexNext();
 
     auto* stop = last->lexNext();
+
+    bool has_read = false, has_write = false;
+
     for (auto* st = start; st != stop; st = st->lexNext())
-        for (int i = 0; i < 3; i++)
-            replaceArrayRec(replace_symb, replace_by, st->expr(i));
+        replaceArrayRec(replace_symb, replace_by, st, has_read, has_write);
 
-    // A_copy = A
-    SgAssignStmt* assign = new SgAssignStmt(*new SgArrayRefExp(*replace_by), *new SgArrayRefExp(*replace_symb));
-    assign->setlineNumber(getNextNegativeLineNumber()); // before region
-    auto* parent = start->controlParent();
-    if (parent && parent->lastNodeOfStmt() == start)
-        parent = parent->controlParent();
 
-    start->insertStmtAfter(*assign, *parent);
+    if (has_read)
+    {
+        // A_copy = A
+        SgAssignStmt* assign = new SgAssignStmt(*new SgArrayRefExp(*replace_by), *new SgArrayRefExp(*replace_symb));
+        assign->setlineNumber(getNextNegativeLineNumber()); // before region
+        auto* parent = start->controlParent();
+        if (parent && parent->lastNodeOfStmt() == start)
+            parent = parent->controlParent();
 
-    // A = A_reg
-    assign = new SgAssignStmt(*new SgArrayRefExp(*replace_symb), *new SgArrayRefExp(*replace_by));
-    //TODO: bug with insertion
-    //assign->setlineNumber(getNextNegativeLineNumber()); // after region
-    last->insertStmtBefore(*assign, *(last->controlParent()));
+        start->insertStmtAfter(*assign, *parent);
+    }
+
+    if (has_write)
+    {
+        // A = A_reg
+        SgAssignStmt* assign = new SgAssignStmt(*new SgArrayRefExp(*replace_symb), *new SgArrayRefExp(*replace_by));
+        //TODO: bug with insertion
+        //assign->setlineNumber(getNextNegativeLineNumber()); // after region
+        last->insertStmtBefore(*assign, *(last->controlParent()));
+    }
 }
 
 static void replaceArrayInFragment(DIST::Array* arr, const set<SgStatement*> usages, SgSymbol* replace_by, SgStatement* start, SgStatement* last, const string& filename)