isl: detect vector parallelism

llvm-svn: 170138

polly/lib/CodeGen/IslAst.cpp

@@ -81,6 +81,9 @@ static void IslAstUserFree(void *User)
 struct AstNodeUserInfo {
   // The node is the outermost parallel loop.
   int IsOutermostParallel;
+
+  // The node is the innermost parallel loop.
+  int IsInnermostParallel;
 };
 
 // Temporary information used when building the ast.
@@ -92,16 +95,22 @@ struct AstBuildUserInfo {
   int InParallelFor;
 };
 
-// Print a loop annotated with OpenMP pragmas.
+// Print a loop annotated with OpenMP or vector pragmas.
 static __isl_give isl_printer *
 printParallelFor(__isl_keep isl_ast_node *Node, __isl_take isl_printer *Printer,
                  __isl_take isl_ast_print_options *PrintOptions,
                  AstNodeUserInfo *Info) {
-  if (Info && Info->IsOutermostParallel) {
-    Printer = isl_printer_start_line(Printer);
-    if (Info->IsOutermostParallel)
+  if (Info) {
+    if (Info->IsInnermostParallel) {
+      Printer = isl_printer_start_line(Printer);
+      Printer = isl_printer_print_str(Printer, "#pragma simd");
+      Printer = isl_printer_end_line(Printer);
+    }
+    if (Info->IsOutermostParallel) {
+      Printer = isl_printer_start_line(Printer);
       Printer = isl_printer_print_str(Printer, "#pragma omp parallel for");
-    Printer = isl_printer_end_line(Printer);
+      Printer = isl_printer_end_line(Printer);
+    }
   }
   return isl_ast_node_for_print(Node, Printer, PrintOptions);
 }
@@ -126,6 +135,7 @@ static struct AstNodeUserInfo *allocateAstNodeUserInfo() {
   struct AstNodeUserInfo *NodeInfo;
   NodeInfo = (struct AstNodeUserInfo *) malloc(sizeof(struct AstNodeUserInfo));
   NodeInfo->IsOutermostParallel = 0;
+  NodeInfo->IsInnermostParallel = 0;
   return NodeInfo;
 }
 
@@ -223,6 +233,46 @@ static __isl_give isl_id *astBuildBeforeFor(__isl_keep isl_ast_build *Build,
   return Id;
 }
 
+// Returns 0 when Node contains loops, otherwise returns -1. This search
+// function uses ISL's way to iterate over lists of isl_ast_nodes with
+// isl_ast_node_list_foreach. Please use the single argument wrapper function
+// that returns a bool instead of using this function directly.
+static int containsLoops(__isl_take isl_ast_node *Node, void *User) {
+  if (!Node)
+    return -1;
+
+  switch (isl_ast_node_get_type(Node)) {
+  case isl_ast_node_for:
+    isl_ast_node_free(Node);
+    return 0;
+  case isl_ast_node_block: {
+    isl_ast_node_list *List = isl_ast_node_block_get_children(Node); 
+    int Res = isl_ast_node_list_foreach(List, &containsLoops, NULL);
+    isl_ast_node_list_free(List);
+    isl_ast_node_free(Node);
+    return Res;
+  }
+  case isl_ast_node_if: {
+    int Res = -1;
+    if (0 == containsLoops(isl_ast_node_if_get_then(Node), NULL) ||
+        (isl_ast_node_if_has_else(Node) &&
+         0 == containsLoops(isl_ast_node_if_get_else(Node), NULL)))
+      Res = 0;
+    isl_ast_node_free(Node);
+    return Res;
+  }
+  case isl_ast_node_user:
+  default:
+    isl_ast_node_free(Node);
+    return -1;
+  }
+}
+
+// Returns true when Node contains loops.
+static bool containsLoops(__isl_take isl_ast_node *Node) {
+  return 0 == containsLoops(Node, NULL);
+}
+
 // This method is executed after the construction of a for node.
 //
 // It performs the following actions:
@@ -233,17 +283,17 @@ static __isl_give isl_id *astBuildBeforeFor(__isl_keep isl_ast_build *Build,
 static __isl_give isl_ast_node *
 astBuildAfterFor(__isl_take isl_ast_node *Node,
                  __isl_keep isl_ast_build *Build, void *User) {
-  isl_id *Id;
-  struct AstBuildUserInfo *BuildInfo;
-  struct AstNodeUserInfo *Info;
-
-  Id = isl_ast_node_get_annotation(Node);
+  isl_id *Id = isl_ast_node_get_annotation(Node);
   if (!Id)
     return Node;
-  Info = (struct AstNodeUserInfo *) isl_id_get_user(Id);
-  if (Info && Info->IsOutermostParallel) {
-    BuildInfo = (struct AstBuildUserInfo *) User;
-    BuildInfo->InParallelFor = 0;
+  struct AstNodeUserInfo *Info = (struct AstNodeUserInfo *) isl_id_get_user(Id);
+  struct AstBuildUserInfo *BuildInfo = (struct AstBuildUserInfo *) User;
+  if (Info) {
+    if (Info->IsOutermostParallel)
+      BuildInfo->InParallelFor = 0;
+    if (!containsLoops(isl_ast_node_for_get_body(Node)))
+      if (astScheduleDimIsParallel(Build, BuildInfo->Deps))
+        Info->IsInnermostParallel = 1;
   }
 
   isl_id_free(Id);

polly/test/Isl/Ast/OpenMP/nested_loop_both_parallel_parametric.ll

@@ -50,6 +50,7 @@ ret:
 ; memory accesses, that would happen if n >= 1024.
 ;
 ; CHECK: for (int c1 = 0; c1 < n; c1 += 1)
+; CHECK:   #pragma simd
 ; CHECK:   #pragma omp parallel for
 ; CHECK:   for (int c3 = 0; c3 < n; c3 += 1)
 ; CHECK:     Stmt_loop_body(c1, c3);

polly/test/Isl/Ast/OpenMP/nested_loop_inner_parallel.ll

@@ -41,6 +41,7 @@ ret:
 }
 
 ; CHECK: for (int c1 = 0; c1 < n; c1 += 1)
+; CHECK:   #pragma simd
 ; CHECK:   #pragma omp parallel for
 ; CHECK:   for (int c3 = 0; c3 < n; c3 += 1)
 ; CHECK:     Stmt_loop_body(c1, c3);

polly/test/Isl/Ast/OpenMP/single_loop_param_parallel.ll

@@ -30,6 +30,7 @@ ret:
   ret void
 }
 
+; CHECK: #pragma simd
 ; CHECK: #pragma omp parallel for
 ; CHECK: for (int c1 = 0; c1 < n; c1 += 1)
 ; CHECK:   Stmt_loop_body(c1)