re PR tree-optimization/57370 (compiler hangs in reassoc)

2013-09-04  Easwaran Raman  <eraman@google.com>

	PR middle-end/57370
	PR tree-optimization/58011
	* tree-ssa-reassoc.c (get_stmt_uid_with_default): New function,
	(build_and_add_sum): Use it.
	(appears_later_in_bb): Simplify code.

gcc/testsuite/ChangeLog:
2013-09-04  Easwaran Raman  <eraman@google.com>

	PR middle-end/57370
	PR tree-optimization/58011
	* gfortran.dg/reassoc_12.f90: New testcase.
	* gcc.dg/tree-ssa/reassoc-31.c: New testcase.

From-SVN: r202262

gcc/ChangeLog

+2013-09-04  Easwaran Raman  <eraman@google.com>
+
+	PR middle-end/57370
+	* tree-ssa-reassoc.c (get_stmt_uid_with_default): New function,
+	(build_and_add_sum): Use it.
+	(appears_later_in_bb): Simplify code.
+
 2013-09-04  Teresa Johnson  <tejohnson@google.com>
 
 	* dumpfile.c (dump_finish): Don't close stderr/stdout.

gcc/testsuite/ChangeLog

+2013-09-04  Easwaran Raman  <eraman@google.com>
+
+	PR middle-end/57370
+	PR tree-optimization/58011
+	* gfortran.dg/reassoc_12.f90: New testcase.
+	* gcc.dg/tree-ssa/reassoc-31.c: New testcase.
+
 2013-09-04  David Edelsohn  <dje.gcc@gmail.com>
 
 	* gcc.dg/attr-weakref-1.c: Skip on AIX.

gcc/testsuite/gcc.dg/tree-ssa/reassoc-31.c

+/* PR tree-optimization/58011 */
+/* { dg-do compile } */
+/* { dg-options "-O1" } */
+int a, b;
+
+void f(unsigned p)
+{
+    unsigned *pp = &p;
+
+    if(!a)
+        p = 0;
+
+    for(b = 0; b < 1; b++)
+        if(3 * p + 5 * *pp)
+            a = 0;
+}
+

gcc/testsuite/gfortran.dg/reassoc_12.f90

+! { dg-do compile }
+! { dg-options "-O2 -ffast-math" }
+! PR middle-end/57370
+
+ SUBROUTINE xb88_lr_adiabatic_lda_calc(e_ndrho_ndrho_ndrho, &
+                                       grad_deriv,npoints, sx)
+    IMPLICIT REAL*8 (t)
+    INTEGER, PARAMETER :: dp=8
+    REAL(kind=dp), DIMENSION(1:npoints) :: e_ndrho_ndrho_ndrho, &
+                                           e_ndrho_ndrho_rho
+      DO ii=1,npoints
+          IF( grad_deriv >= 2 .OR. grad_deriv == -2 ) THEN
+            t1425 = t233 * t557
+            t1429 = beta * t225
+            t1622 = t327 * t1621
+            t1626 = t327 * t1625
+            t1632 = t327 * t1631
+            t1685 = t105 * t1684
+            t2057 = t1636 + t8 * (t2635 + t3288)
+          END IF
+          IF( grad_deriv >= 3 .OR. grad_deriv == -3 ) THEN
+            t5469 = t5440 - t5443 - t5446 - t5449 - &
+                    t5451 - t5454 - t5456 + t5459  - &
+                    t5462 + t5466 - t5468
+            t5478 = 0.240e2_dp * t1616 * t973 * t645 * t1425
+            t5489 = 0.1600000000e2_dp * t1429 * t1658
+            t5531 = 0.160e2_dp * t112 * t1626
+            t5533 = 0.160e2_dp * t112 * t1632
+            t5537 = 0.160e2_dp * t112 * t1622
+            t5541 = t5472 - t5478 - t5523 + t5525 + &
+                    t5531 + t5533 + t5535 + t5537 + &
+                    t5540
+            t5565 = t112 * t1685
+            t5575 = t5545 - t5548 + t5551 + t5553 - &
+                    t5558 + t5560 - t5562 + t5564 - &
+                    0.80e1_dp * t5565 + t5568 + t5572 + &
+                    t5574
+            t5611 = t5579 - t5585 + t5590 - t5595 + &
+                    t5597 - t5602 + t5604 + t5607 + &
+                    t5610
+            t5613 = t5469 + t5541 + t5575 + t5611
+            t6223 = t6189 - &
+                    0.3333333336e0_dp  * t83 * t84 * t5613 + &
+                    t6222
+            t6227 = - t8 * (t5305 + t6223)
+            e_ndrho_ndrho_rho(ii) = e_ndrho_ndrho_rho(ii) + &
+                     t6227 * sx
+            t6352 = t5440 - t5443 - t5446 - t5449 - &
+                    t5451 - t5454 + &
+                    0.40e1_dp * t102  * t327 * t2057 * t557 - &
+                    t5456 + t5459 - t5462 + t5466 - &
+                    t5468
+            t6363 = t5480 - t5489 + &
+                    0.9600000000e2_dp  * t1054 * t640 * t3679
+            t6367 = t5472 - t5474 - t5478 - t5523 + &
+                    t5525 + t5531 + t5533 + t5535 + &
+                    t5537 - 0.20e1_dp * t102 * t105 * t6363 + &
+                    t5540
+            t6370 = t5545 - t5548 + t5551 + t5553 - &
+                    t5558 + t5560 - t5562 + t5564  - &
+                    0.40e1_dp * t5565 + &
+                    t5568 + t5572 + t5574
+            t6373 = t5579 - t5585 + t5590 - t5595 + &
+                    t5597 - t5602 + t5604 + t5607 + &
+                    t5610
+            t6375 = t6352 + t6367 + t6370 + t6373
+            t6380 = - 0.3333333336e0_dp * t83 * t84 * t6375 + t5701
+            t6669 = -t4704 - t8 * (t6344 + t6380 + t6665)
+            e_ndrho_ndrho_ndrho(ii) = e_ndrho_ndrho_ndrho(ii) + &
+                     t6669 * sx
+          END IF
+      END DO
+  END SUBROUTINE xb88_lr_adiabatic_lda_calc
+

gcc/tree-ssa-reassoc.c

@@ -1141,6 +1141,14 @@ zero_one_operation (tree *def, enum tree_code opcode, tree op)
   while (1);
 }
 
+/* Returns the UID of STMT if it is non-NULL. Otherwise return 1.  */
+
+static inline unsigned
+get_stmt_uid_with_default (gimple stmt)
+{
+  return stmt ? gimple_uid (stmt) : 1;
+}
+
 /* Builds one statement performing OP1 OPCODE OP2 using TMPVAR for
    the result.  Places the statement after the definition of either
    OP1 or OP2.  Returns the new statement.  */
@@ -1165,12 +1173,8 @@ build_and_add_sum (tree type, tree op1, tree op2, enum tree_code opcode)
   if ((!op1def || gimple_nop_p (op1def))
       && (!op2def || gimple_nop_p (op2def)))
     {
-      gimple first_stmt;
-      unsigned uid;
       gsi = gsi_after_labels (single_succ (ENTRY_BLOCK_PTR));
-      first_stmt = gsi_stmt (gsi);
-      uid = first_stmt ? gimple_uid (first_stmt) : 1;
-      gimple_set_uid (sum, uid);
+      gimple_set_uid (sum, get_stmt_uid_with_default (gsi_stmt (gsi)));
       gsi_insert_before (&gsi, sum, GSI_NEW_STMT);
     }
   else if ((!op1def || gimple_nop_p (op1def))
@@ -1180,7 +1184,7 @@ build_and_add_sum (tree type, tree op1, tree op2, enum tree_code opcode)
       if (gimple_code (op2def) == GIMPLE_PHI)
 	{
 	  gsi = gsi_after_labels (gimple_bb (op2def));
-          gimple_set_uid (sum, gimple_uid (gsi_stmt (gsi)));
+          gimple_set_uid (sum, get_stmt_uid_with_default (gsi_stmt (gsi)));
 	  gsi_insert_before (&gsi, sum, GSI_NEW_STMT);
 	}
       else
@@ -1207,7 +1211,7 @@ build_and_add_sum (tree type, tree op1, tree op2, enum tree_code opcode)
       if (gimple_code (op1def) == GIMPLE_PHI)
 	{
 	  gsi = gsi_after_labels (gimple_bb (op1def));
-          gimple_set_uid (sum, gimple_uid (op1def));
+          gimple_set_uid (sum, get_stmt_uid_with_default (gsi_stmt (gsi)));
 	  gsi_insert_before (&gsi, sum, GSI_NEW_STMT);
 	}
       else
@@ -2874,10 +2878,7 @@ appears_later_in_bb (gimple stmt1, gimple stmt2)
 {
   unsigned uid = gimple_uid (stmt1);
   gimple_stmt_iterator gsi = gsi_for_stmt (stmt1);
-  gsi_next (&gsi);
-  if (gsi_end_p (gsi))
-    return stmt1;
-  for (; !gsi_end_p (gsi); gsi_next (&gsi))
+  for (gsi_next (&gsi); !gsi_end_p (gsi); gsi_next (&gsi))
     {
       gimple stmt = gsi_stmt (gsi);