fix PR68550: do not handle ISL loop peeled statements

In case ISL did some loop peeling, like this:

  S_8(0);
  for (int c1 = 1; c1 <= 5; c1 += 1) {
    S_8(c1);
  }
  S_8(6);

we should not copy loop-phi nodes in S_8(0) or in S_8(6).

	PR tree-optimization/68550
	* graphite-isl-ast-to-gimple.c (copy_loop_phi_nodes): Add dump.
	(copy_bb_and_scalar_dependences): Do not code generate loop peeled
	statements.

	* gfortran.dg/graphite/pr68550-1.f90: New.
	* gfortran.dg/graphite/pr68550-2.f90: New.

Co-Authored-By: Sebastian Pop <s.pop@samsung.com>

From-SVN: r231206

gcc/ChangeLog

+2015-12-02  Aditya Kumar  <aditya.k7@samsung.com>
+	    Sebastian Pop  <s.pop@samsung.com>
+
+	PR tree-optimization/68550
+	* graphite-isl-ast-to-gimple.c (copy_loop_phi_nodes): Add dump.
+	(copy_bb_and_scalar_dependences): Do not code generate loop peeled
+	statements.
+
 2015-12-02  Ulrich Weigand  <Ulrich.Weigand@de.ibm.com>
 
 	* configure.ac: Check assembler support for R_PPC64_ENTRY relocation.

gcc/graphite-isl-ast-to-gimple.c

@@ -2096,6 +2096,12 @@ translate_isl_ast_to_gimple::copy_loop_phi_nodes (basic_block bb,
       codegen_error = !copy_loop_phi_args (phi, ibp_old_bb, new_phi,
 					  ibp_new_bb, true);
       update_stmt (new_phi);
+
+      if (dump_file)
+	{
+	  fprintf (dump_file, "[codegen] creating loop-phi node: ");
+	  print_gimple_stmt (dump_file, new_phi, 0, 0);
+	}
     }
 
   return true;
@@ -2894,6 +2900,26 @@ translate_isl_ast_to_gimple::copy_bb_and_scalar_dependences (basic_block bb,
 	      return NULL;
 	    }
 
+	  /* In case ISL did some loop peeling, like this:
+
+	       S_8(0);
+	       for (int c1 = 1; c1 <= 5; c1 += 1) {
+	         S_8(c1);
+	       }
+	       S_8(6);
+
+	     there should be no loop-phi nodes in S_8(0).
+
+	     FIXME: We need to reason about dynamic instances of S_8, i.e., the
+	     values of all scalar variables: for the moment we instantiate only
+	     SCEV analyzable expressions on the iteration domain, and we need to
+	     extend that to reductions that cannot be analyzed by SCEV.  */
+	  if (!bb_in_sese_p (phi_bb, region->if_region->true_region->region))
+	    {
+	      codegen_error = true;
+	      return NULL;
+	    }
+
 	  if (dump_file)
 	    fprintf (dump_file, "[codegen] bb_%d contains loop phi nodes.\n",
 		     bb->index);

gcc/testsuite/ChangeLog

+2015-12-02  Aditya Kumar  <aditya.k7@samsung.com>
+	    Sebastian Pop  <s.pop@samsung.com>
+
+	PR tree-optimization/68550
+	* gfortran.dg/graphite/pr68550-1.f90: New.
+	* gfortran.dg/graphite/pr68550-2.f90: New.
+
 2015-12-02  Marek Polacek  <polacek@redhat.com>
 
 	PR c/68513

gcc/testsuite/gfortran.dg/graphite/pr68550-1.f90

+! { dg-do compile }
+! { dg-options "-floop-nest-optimize -O2" }
+
+SUBROUTINE integrate_core_1(grid,coef_xyz,pol_x,pol_y,&
+             pol_z,map,sphere_bounds,cmax,gridbounds)
+    INTEGER, PARAMETER :: dp=8
+    INTEGER, INTENT(IN)    :: sphere_bounds(*), cmax, &
+                              map(-cmax:cmax,1:3), &
+                              gridbounds(2,3)
+    REAL(dp), INTENT(IN) :: grid(gridbounds(1,1):gridbounds(2,1), &
+             gridbounds(1,2):gridbounds(2,2),&
+             gridbounds(1,3):gridbounds(2,3))
+    INTEGER, PARAMETER     :: lp = 1
+    REAL(dp), INTENT(IN)   :: pol_x(0:lp,-cmax:cmax), &
+                              pol_y(1:2,0:lp,-cmax:0), &
+                              pol_z(1:2,0:lp,-cmax:0)
+    REAL(dp), INTENT(OUT) :: coef_xyz(((lp+1)*(lp+2)*(lp+3))/6)
+    INTEGER   :: i, ig, igmax, igmin, j, j2, &
+                 jg, jg2, jgmin, k, k2, kg, &
+                 kg2, kgmin, lxp, sci
+    REAL(dp)  :: coef_x(4,0:lp), &
+                 coef_xy(2,((lp+1)*(lp+2))/2), &
+                 s(4)
+    DO kg=kgmin,0
+       DO jg=jgmin,0
+          coef_x=0.0_dp
+          DO ig=igmin,igmax
+             DO lxp=0,lp
+                coef_x(:,lxp)=coef_x(:,lxp)+s(:)*pol_x(lxp,ig)
+             ENDDO
+          END DO
+             coef_xy(:,3)=coef_xy(:,3)+coef_x(3:4,0)*pol_y(2,1,jg)
+       END DO
+                coef_xyz(3)=coef_xyz(3)+coef_xy(1,3)*pol_z(1,0,kg)
+    END DO
+  END SUBROUTINE integrate_core_1

gcc/testsuite/gfortran.dg/graphite/pr68550-2.f90

+! { dg-do compile }
+! { dg-options "-floop-nest-optimize -fcheck=bounds -O1" }
+
+SUBROUTINE PD2VAL(RES,NDERIV,TG1,TG2,C0)
+    INTEGER, PARAMETER :: dp=8
+    REAL(KIND=dp), INTENT(OUT)  :: res(*)
+    REAL(KIND=dp), INTENT(IN)   :: TG1, TG2, C0(105,*)
+    REAL(KIND=dp)               :: T1(0:13), T2(0:13)
+ DO K=1,NDERIV+1
+  RES(K)=RES(K)+DOT_PRODUCT(T1(0:7),C0(70:77,K))*T2(6)
+  RES(K)=RES(K)+DOT_PRODUCT(T1(0:4),C0(91:95,K))*T2(9)
+  RES(K)=RES(K)+DOT_PRODUCT(T1(0:3),C0(96:99,K))*T2(10)
+ ENDDO
+END SUBROUTINE PD2VAL