2012-11-22 Dmitry Vyukov <dvyukov@google.com>

	    Wei Mi  <wmi@google.com>

	* builtins.def (DEF_SANITIZER_BUILTIN): Define tsan builtins. 
	* sanitizer.def: Ditto. 
	* Makefile.in (tsan.o): Add tsan.o target. 
	(BUILTINS_DEF): Add sanitizer.def.
	* passes.c (init_optimization_passes): Add tsan passes.
	* tree-pass.h (register_pass_info): Ditto.
	* toplev.c (compile_file): Ditto. 
	* doc/invoke.texi: Document tsan related options.
	* gcc.c (LINK_COMMAND_SPEC): Add LIBTSAN_SPEC in link command if
	-fsanitize=thread.
	* tsan.c: New file about tsan.
	* tsan.h: Ditto.
	* common.opt: Add -fsanitize=thread.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@193736 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 405 insertions, 0 deletions

diff --git a/gcc/tsan.c b/gcc/tsan.c
new file mode 100644
index 00000000000..8660b87addd
--- /dev/null
+++ b/gcc/tsan.c
@@ -0,0 +1,405 @@
+/* GCC instrumentation plugin for ThreadSanitizer.
+   Copyright (C) 2011, 2012 Free Software Foundation, Inc.
+   Contributed by Dmitry Vyukov <dvyukov@google.com>
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC is distributed in the hope that it will be useful, but WITHOUT ANY
+WARRANTY; without even the implied warranty of MERCHANTABILITY or
+FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+for more details.
+
+You should have received a copy of the GNU General Public License
+along with GCC; see the file COPYING3.  If not see
+<http://www.gnu.org/licenses/>.  */
+
+
+#include "config.h"
+#include "system.h"
+#include "coretypes.h"
+#include "tree.h"
+#include "intl.h"
+#include "tm.h"
+#include "basic-block.h"
+#include "gimple.h"
+#include "function.h"
+#include "tree-flow.h"
+#include "tree-pass.h"
+#include "tree-iterator.h"
+#include "langhooks.h"
+#include "output.h"
+#include "options.h"
+#include "target.h"
+#include "cgraph.h"
+#include "diagnostic.h"
+
+/* Number of instrumented memory accesses in the current function.  */
+
+/* Builds the following decl
+   void __tsan_read/writeX (void *addr);  */
+
+static tree
+get_memory_access_decl (bool is_write, unsigned size)
+{
+  enum built_in_function fcode;
+
+  if (size <= 1)
+    fcode = is_write ? BUILT_IN_TSAN_WRITE_1
+		     : BUILT_IN_TSAN_READ_1;
+  else if (size <= 3)
+    fcode = is_write ? BUILT_IN_TSAN_WRITE_2
+		     : BUILT_IN_TSAN_READ_2;
+  else if (size <= 7)
+    fcode = is_write ? BUILT_IN_TSAN_WRITE_4
+		     : BUILT_IN_TSAN_READ_4;
+  else if (size <= 15)
+    fcode = is_write ? BUILT_IN_TSAN_WRITE_8
+		     : BUILT_IN_TSAN_READ_8;
+  else
+    fcode = is_write ? BUILT_IN_TSAN_WRITE_16
+		     : BUILT_IN_TSAN_READ_16;
+
+  return builtin_decl_implicit (fcode);
+}
+
+/* Check as to whether EXPR refers to a store to vptr.  */
+
+static tree
+is_vptr_store (gimple stmt, tree expr, bool is_write)
+{
+  if (is_write == true
+      && gimple_assign_single_p (stmt)
+      && TREE_CODE (expr) == COMPONENT_REF)
+    {
+      tree field = TREE_OPERAND (expr, 1);
+      if (TREE_CODE (field) == FIELD_DECL
+	  && DECL_VIRTUAL_P (field))
+	return gimple_assign_rhs1 (stmt);
+    }
+  return NULL;
+}
+
+/* Checks as to whether EXPR refers to constant var/field/param.
+   Don't bother to instrument them.  */
+
+static bool
+is_load_of_const_p (tree expr, bool is_write)
+{
+  if (is_write)
+    return false;
+  if (TREE_CODE (expr) == COMPONENT_REF)
+    expr = TREE_OPERAND (expr, 1);
+  if (TREE_CODE (expr) == VAR_DECL
+      || TREE_CODE (expr) == PARM_DECL
+      || TREE_CODE (expr) == FIELD_DECL)
+    {
+      if (TREE_READONLY (expr))
+	return true;
+    }
+  return false;
+}
+
+/* Instruments EXPR if needed. If any instrumentation is inserted,
+ * return true. */
+
+static bool
+instrument_expr (gimple_stmt_iterator gsi, tree expr, bool is_write)
+{
+  enum tree_code tcode;
+  tree base, rhs, expr_type, expr_ptr, builtin_decl;
+  basic_block bb;
+  HOST_WIDE_INT size;
+  gimple stmt, g;
+  location_t loc;
+
+  base = get_base_address (expr);
+  if (base == NULL_TREE
+      || TREE_CODE (base) == SSA_NAME
+      || TREE_CODE (base) == STRING_CST)
+    return false;
+
+  tcode = TREE_CODE (expr);
+
+  /* Below are things we do not instrument
+     (no possibility of races or not implemented yet).  */
+  if (/* Compiler-emitted artificial variables.  */
+      (DECL_P (expr) && DECL_ARTIFICIAL (expr))
+      /* The var does not live in memory -> no possibility of races.  */
+      || (tcode == VAR_DECL
+	  && !TREE_ADDRESSABLE (expr)
+	  && TREE_STATIC (expr) == 0)
+      /* Not implemented.  */
+      || TREE_CODE (TREE_TYPE (expr)) == RECORD_TYPE
+      /* Not implemented.  */
+      || tcode == CONSTRUCTOR
+      /* Not implemented.  */
+      || tcode == PARM_DECL
+      /* Load of a const variable/parameter/field.  */
+      || is_load_of_const_p (expr, is_write))
+    return false;
+
+  size = int_size_in_bytes (TREE_TYPE (expr));
+  if (size == -1)
+    return false;
+
+  /* For now just avoid instrumenting bit field acceses.
+     TODO: handle bit-fields as if touching the whole field.  */
+  HOST_WIDE_INT bitsize, bitpos;
+  tree offset;
+  enum machine_mode mode;
+  int volatilep = 0, unsignedp = 0;
+  get_inner_reference (expr, &bitsize, &bitpos, &offset,
+		       &mode, &unsignedp, &volatilep, false);
+  if (bitpos % (size * BITS_PER_UNIT)
+      || bitsize != size * BITS_PER_UNIT)
+    return false;
+
+  /* TODO: handle other case: ARRAY_RANGE_REF. */
+  if (tcode != ARRAY_REF
+      && tcode != VAR_DECL
+      && tcode != COMPONENT_REF
+      && tcode != INDIRECT_REF
+      && tcode != MEM_REF)
+    return false;
+
+  stmt = gsi_stmt (gsi);
+  loc = gimple_location (stmt);
+  rhs = is_vptr_store (stmt, expr, is_write);
+  gcc_checking_assert (rhs != NULL || is_gimple_addressable (expr));
+  expr_ptr = build_fold_addr_expr (unshare_expr (expr));
+  if (rhs == NULL)
+    {
+      expr_type = TREE_TYPE (expr);
+      while (TREE_CODE (expr_type) == ARRAY_TYPE)
+	expr_type = TREE_TYPE (expr_type);
+      size = int_size_in_bytes (expr_type);
+      g = gimple_build_call (get_memory_access_decl (is_write, size),
+			     1, expr_ptr);
+    }
+  else
+    {
+      builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_VPTR_UPDATE);
+      g = gimple_build_call (builtin_decl, 1, expr_ptr);
+    }
+  gimple_set_location (g, loc);
+  /* Instrumentation for assignment of a function result
+     must be inserted after the call.  Instrumentation for
+     reads of function arguments must be inserted before the call.
+     That's because the call can contain synchronization.  */
+  if (is_gimple_call (stmt) && is_write)
+    {
+      /* If the call can throw, it must be the last stmt in
+	 a basic block, so the instrumented stmts need to be
+	 inserted in successor bbs. */
+      if (is_ctrl_altering_stmt (stmt))
+	{
+	  edge e;
+
+	  bb = gsi_bb (gsi);
+	  e = find_fallthru_edge (bb->succs);
+	  if (e)
+	    gsi_insert_seq_on_edge_immediate (e, g);
+	}
+      else
+	gsi_insert_after (&gsi, g, GSI_NEW_STMT);
+    }
+  else
+    gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+
+  return true;
+}
+
+/* Instruments the gimple pointed to by GSI. Return
+ * true if func entry/exit should be instrumented. */
+
+static bool
+instrument_gimple (gimple_stmt_iterator gsi)
+{
+  gimple stmt;
+  tree rhs, lhs;
+  bool instrumented = false;
+
+  stmt = gsi_stmt (gsi);
+  if (is_gimple_call (stmt)
+      && (gimple_call_fndecl (stmt)
+	  != builtin_decl_implicit (BUILT_IN_TSAN_INIT)))
+    return true;
+  else if (is_gimple_assign (stmt))
+    {
+      if (gimple_store_p (stmt))
+	{
+	  lhs = gimple_assign_lhs (stmt);
+	  instrumented = instrument_expr (gsi, lhs, true);
+	}
+      if (gimple_assign_load_p (stmt))
+	{
+	  rhs = gimple_assign_rhs1 (stmt);
+	  instrumented = instrument_expr (gsi, rhs, false);
+	}
+    }
+  return instrumented;
+}
+
+/* Instruments all interesting memory accesses in the current function.
+ * Return true if func entry/exit should be instrumented. */
+
+static bool
+instrument_memory_accesses (void)
+{
+  basic_block bb;
+  gimple_stmt_iterator gsi;
+  bool fentry_exit_instrument = false;
+
+  FOR_EACH_BB (bb)
+    for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
+      fentry_exit_instrument |= instrument_gimple (gsi);
+  return fentry_exit_instrument;
+}
+
+/* Instruments function entry.  */
+
+static void
+instrument_func_entry (void)
+{
+  basic_block succ_bb;
+  gimple_stmt_iterator gsi;
+  tree ret_addr, builtin_decl;
+  gimple g;
+
+  succ_bb = single_succ (ENTRY_BLOCK_PTR);
+  gsi = gsi_after_labels (succ_bb);
+
+  builtin_decl = builtin_decl_implicit (BUILT_IN_RETURN_ADDRESS);
+  g = gimple_build_call (builtin_decl, 1, integer_zero_node);
+  ret_addr = make_ssa_name (ptr_type_node, NULL);
+  gimple_call_set_lhs (g, ret_addr);
+  gimple_set_location (g, cfun->function_start_locus);
+  gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+
+  builtin_decl =  builtin_decl_implicit (BUILT_IN_TSAN_FUNC_ENTRY);
+  g = gimple_build_call (builtin_decl, 1, ret_addr);
+  gimple_set_location (g, cfun->function_start_locus);
+  gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+}
+
+/* Instruments function exits.  */
+
+static void
+instrument_func_exit (void)
+{
+  location_t loc;
+  basic_block exit_bb;
+  gimple_stmt_iterator gsi;
+  gimple stmt, g;
+  tree builtin_decl;
+  edge e;
+  edge_iterator ei;
+
+  /* Find all function exits.  */
+  exit_bb = EXIT_BLOCK_PTR;
+  FOR_EACH_EDGE (e, ei, exit_bb->preds)
+    {
+      gsi = gsi_last_bb (e->src);
+      stmt = gsi_stmt (gsi);
+      gcc_assert (gimple_code (stmt) == GIMPLE_RETURN);
+      loc = gimple_location (stmt);
+      builtin_decl = builtin_decl_implicit (BUILT_IN_TSAN_FUNC_EXIT);
+      g = gimple_build_call (builtin_decl, 0);
+      gimple_set_location (g, loc);
+      gsi_insert_before (&gsi, g, GSI_SAME_STMT);
+    }
+}
+
+/* ThreadSanitizer instrumentation pass.  */
+
+static unsigned
+tsan_pass (void)
+{
+  if (instrument_memory_accesses ())
+    {
+      instrument_func_entry ();
+      instrument_func_exit ();
+    }
+  return 0;
+}
+
+/* The pass's gate.  */
+
+static bool
+tsan_gate (void)
+{
+  return flag_tsan != 0
+	 && builtin_decl_implicit_p (BUILT_IN_TSAN_INIT);
+}
+
+/* Inserts __tsan_init () into the list of CTORs.  */
+
+void
+tsan_finish_file (void)
+{
+  tree ctor_statements;
+  tree init_decl;
+
+  ctor_statements = NULL_TREE;
+  init_decl = builtin_decl_implicit (BUILT_IN_TSAN_INIT);
+  append_to_statement_list (build_call_expr (init_decl, 0),
+			    &ctor_statements);
+  cgraph_build_static_cdtor ('I', ctor_statements,
+			     MAX_RESERVED_INIT_PRIORITY - 1);
+}
+
+/* The pass descriptor.  */
+
+struct gimple_opt_pass pass_tsan =
+{
+ {
+  GIMPLE_PASS,
+  "tsan",				/* name  */
+  OPTGROUP_NONE,			/* optinfo_flags */
+  tsan_gate,				/* gate  */
+  tsan_pass,				/* execute  */
+  NULL,					/* sub  */
+  NULL,					/* next  */
+  0,					/* static_pass_number  */
+  TV_NONE,				/* tv_id  */
+  PROP_ssa | PROP_cfg,			/* properties_required  */
+  0,					/* properties_provided  */
+  0,					/* properties_destroyed  */
+  0,					/* todo_flags_start  */
+  TODO_verify_all | TODO_update_ssa
+  | TODO_update_address_taken		/* todo_flags_finish  */
+ }
+};
+
+static bool
+tsan_gate_O0 (void)
+{
+  return flag_tsan != 0 && !optimize
+	 && builtin_decl_implicit_p (BUILT_IN_TSAN_INIT);
+}
+
+struct gimple_opt_pass pass_tsan_O0 =
+{
+ {
+  GIMPLE_PASS,
+  "tsan0",				/* name  */
+  OPTGROUP_NONE,			/* optinfo_flags */
+  tsan_gate_O0,				/* gate  */
+  tsan_pass,				/* execute  */
+  NULL,					/* sub  */
+  NULL,					/* next  */
+  0,					/* static_pass_number  */
+  TV_NONE,				/* tv_id  */
+  PROP_ssa | PROP_cfg,			/* properties_required  */
+  0,					/* properties_provided  */
+  0,					/* properties_destroyed  */
+  0,					/* todo_flags_start  */
+  TODO_verify_all | TODO_update_ssa
+  | TODO_update_address_taken		/* todo_flags_finish  */
+ }
+};