Re: [PATCH] Make SRA produce integer replacements for enumeration types

[Martin Jambor <mjambor at suse dot cz>]

Hi,

On Wed, Sep 07, 2011 at 10:08:29AM +0200, Richard Guenther wrote:
> On Tue, 6 Sep 2011, Martin Jambor wrote:
> > the patch below makes SRA produce intere type replacements when it
> > currently produces enumeration type ones because this then may cause
> > VRP to assume wrong bounds (PR 49911).
> > 
> > I do not know how to create a testcase for the PR this should solve
> > because I could not reproduce it on yesterday's trunk checkout.
> > 
> > The patch is against trunk, where it successfully passes bootstrap and
> > testing on x86_64-linux, but applies well also to 4.6 and 4.5 branches
> > and there has been a request to commit them there as well so I'd like
> > to do so (after testing it on them which I have not done yet).
> > 
> > OK?
> 
> Ok.  Can you add the testcase from the PR?
> 

Well, as I said, it does not fail even wothout the patch but why not.
This is the patch I wichh commit in a few moments.

Thanks,

Martin

2011-09-07  Martin Jambor  <mjambor@suse.cz>

	PR tree-optimization/49911
	* tree-sra.c (analyze_access_subtree): Change type of to-be-replaced
	enumerations to the corresponding plain integer type.

	* testsuite/g++.dg/tree-ssa/pr49911.C: New test.

Index: src/gcc/tree-sra.c
===================================================================
--- src.orig/gcc/tree-sra.c
+++ src/gcc/tree-sra.c
@@ -2075,13 +2075,25 @@ analyze_access_subtree (struct access *r
 	  || ((root->grp_scalar_read || root->grp_assignment_read)
 	      && (root->grp_scalar_write || root->grp_assignment_write))))
     {
+      bool new_integer_type;
+      if (TREE_CODE (root->type) == ENUMERAL_TYPE)
+	{
+	  tree rt = root->type;
+	  root->type = build_nonstandard_integer_type (TYPE_PRECISION (rt),
+						       TYPE_UNSIGNED (rt));
+	  new_integer_type = true;
+	}
+      else
+	new_integer_type = false;
+
       if (dump_file && (dump_flags & TDF_DETAILS))
 	{
 	  fprintf (dump_file, "Marking ");
 	  print_generic_expr (dump_file, root->base, 0);
-	  fprintf (dump_file, " offset: %u, size: %u: ",
+	  fprintf (dump_file, " offset: %u, size: %u ",
 		   (unsigned) root->offset, (unsigned) root->size);
-	  fprintf (dump_file, " to be replaced.\n");
+	  fprintf (dump_file, " to be replaced%s.\n",
+		   new_integer_type ? " with an integer": "");
 	}
 
       root->grp_to_be_replaced = 1;
Index: src/gcc/testsuite/g++.dg/tree-ssa/pr49911.C
===================================================================
--- /dev/null
+++ src/gcc/testsuite/g++.dg/tree-ssa/pr49911.C
@@ -0,0 +1,41 @@
+/* { dg-do compile } */
+/* { dg-options "-O2 -fno-rtti -fno-exceptions -fno-strict-aliasing -fdump-tree-vrp2" } */
+
+
+extern  void JS_Assert();
+typedef enum {
+eax,         ecx,         edx,         ebx,         esp,         ebp,
+esi,         edi     }
+RegisterID;
+union StateRemat {
+  RegisterID reg_;
+  int offset_;
+};
+static StateRemat FromRegister(RegisterID reg) {
+  StateRemat sr;
+  sr.reg_ = reg;
+  return sr;
+}
+static StateRemat FromAddress3(int address) {
+  StateRemat sr;
+    sr.offset_ = address;
+  //sr.offset_ = 0;
+  if (address < 46 &&    address >= 0) {
+    JS_Assert();
+  }
+  return sr;
+}
+struct FrameState {
+  StateRemat dataRematInfo2(bool y, int z) {
+    if (y)         return FromRegister(RegisterID(1));
+    return FromAddress3(z);
+  }
+};
+FrameState frame;
+StateRemat x;
+void jsop_setelem(bool y, int z) {
+  x = frame.dataRematInfo2(y, z);
+}
+
+/* { dg-final { scan-tree-dump-times "Folding predicate.*45" 0 "vrp2"} } */
+/* { dg-final { cleanup-tree-dump "vrp2" } } */