Revert r135493 & r135463

From-SVN: r135599

gcc/ChangeLog

+2008-05-19  Xinliang David Li  <davidxl@google.com>
+
+	* tree-ssa-dce.c: Revert patches of 2008-05-17 and 2008-05-18. 
+	* opts.c: Ditto.
+	* common.opt: Ditto.
+	* doc/invoke.texi: Ditto.
+
 2008-05-19  Eric Botcazou  <ebotcazou@adacore.com>
 
 	* tree.c (substitute_in_expr) <tcc_vl_exp>: Fix thinko.

gcc/common.opt

@@ -1259,10 +1259,6 @@ fweb
 Common Report Var(flag_web) Init(2) Optimization
 Construct webs and split unrelated uses of single variable
 
-ftree-builtin-dce
-Common Report Var(flag_tree_builtin_dce) Init(0) Optimization
-Enable conditional dead code elimination for builtin calls.
-
 fwhole-program
 Common Report Var(flag_whole_program) Init(0) Optimization
 Perform whole program optimizations

gcc/doc/invoke.texi

@@ -353,7 +353,7 @@ Objective-C and Objective-C++ Dialects}.
 -fsignaling-nans -fsingle-precision-constant -fsplit-ivs-in-unroller @gol
 -fsplit-wide-types -fstack-protector -fstack-protector-all @gol
 -fstrict-aliasing -fstrict-overflow -fthread-jumps -ftracer -ftree-ccp @gol
--ftree-ch -ftree-copy-prop -ftree-copyrename -ftree-dce -ftree-builtin-dce@gol
+-ftree-ch -ftree-copy-prop -ftree-copyrename -ftree-dce @gol
 -ftree-dominator-opts -ftree-dse -ftree-fre -ftree-loop-im @gol
 -ftree-loop-distribution @gol
 -ftree-loop-ivcanon -ftree-loop-linear -ftree-loop-optimize @gol
@@ -5157,7 +5157,6 @@ compilation time.
 -ftree-ch @gol
 -ftree-copyrename @gol
 -ftree-dce @gol
--ftree-builtin-dce @gol
 -ftree-dominator-opts @gol
 -ftree-dse @gol
 -ftree-fre @gol
@@ -5874,12 +5873,6 @@ enabled by default at @option{-O2} and higher.
 Perform dead code elimination (DCE) on trees.  This flag is enabled by
 default at @option{-O} and higher.
 
-@item -ftree-builtin-dce
-@opindex ftree-builtin-dce
-Perform conditional dead code elimination (DCE) for calls to builtin functions 
-that may set errno but are otherwise side-effect free.  This flag is enabled by
-default at @option{-O2} and higher.
-
 @item -ftree-dominator-opts
 @opindex ftree-dominator-opts
 Perform a variety of simple scalar cleanups (constant/copy

gcc/opts.c

@@ -886,7 +886,6 @@ decode_options (unsigned int argc, const char **argv)
       flag_reorder_functions = 1;
       flag_tree_store_ccp = 1;
       flag_tree_vrp = 1;
-      flag_tree_builtin_dce = 1;
 
       if (!optimize_size)
 	{

gcc/testsuite/ChangeLog

+2008-05-19  Xinliang David Li  <davidxl@google.com>
+
+	* gcc.dg/cdce1.c: Remove test.
+	* gcc.dg/cdce2.c: Remove test.
+
 2008-05-19  Francois-Xavier Coudert  <fxcoudert@gcc.gnu.org>
 
 	PR fortran/36265

gcc/testsuite/gcc.dg/cdce1.c

-/* { dg-do  run } */
-/* { dg-options "-O2 -fdump-tree-dce1-details  -lm" } */
-/* { dg-message  "note: function call is shrink-wrapped into error conditions\." "Missing conditional dce" {target "*-*-*"} 15 } */
- 
-#include <stdlib.h>
-#include <math.h>
-#include <errno.h>
-#include <stdio.h>
-int total_err_count = 0;
-double foo_opt(int x, double y) __attribute__((noinline));
-double foo_opt(int x, double y)
-{
-    double yy = 0;
-    errno = 0;
-    yy = pow(x,y);
-    return 0;
-}
-
-double foo(int x, double y) __attribute__((noinline));
-double foo(int x, double y)
-{
-    double yy = 0;
-    errno = 0;
-    yy = pow(x,y);
-    return yy;
-}
-
-int test(double (*fp)(int x, double y))
-{
-   int i,x;
-
-   x = 127; 
-   for (i = 30; i < 300; i++)
-   {  
-      fp(x,i);
-      if (errno)
-         total_err_count ++;
-   }
-
-   x = -300; 
-   for (i = 100; i < 300; i++)
-   {  
-      fp(x,i);
-      if (errno)
-         total_err_count ++;
-   }
-
-   x = 65577;
-   for (i = 60; i < 200; i++)
-   {  
-      fp(x,i);
-      if (errno)
-         total_err_count ++;
-   }
-
-   x = 65577*127;
-   for (i = 1; i < 100; i++)
-   {  
-      fp(x,i);
-      if (errno)
-         total_err_count ++;
-   }
-
-   return total_err_count;
-}
-
-int main()
-{
-  int en1, en2;
-  total_err_count = 0;
-  en1 = test(foo_opt);
-  total_err_count = 0;
-  en2 = test(foo);
-  
-  printf("total number of errors = %d, %d\n", en1, en2);
-  if (en1 != en2)
-     abort();
-
-  return 0;
-
-}

gcc/testsuite/gcc.dg/cdce2.c

-/* { dg-do  run } */
-/* { dg-options "-O2 -fdump-tree-dce1-details  -lm" } */
-/* { dg-message  "note: function call is shrink-wrapped into error conditions\." "Missing conditional dce" {target "*-*-*"} 15 } */
- 
-#include <stdlib.h>
-#include <math.h>
-#include <errno.h>
-#include <stdio.h>
-int total_err_count = 0;
-double foo_opt(double y) __attribute__((noinline));
-double foo_opt(double y)
-{
-    double yy = 0;
-    errno = 0;
-    yy = log(y);
-    return 0;
-}
-
-double foo(double y) __attribute__((noinline));
-double foo(double y)
-{
-    double yy = 0;
-    errno = 0;
-    yy = log(y);
-    return yy;
-}
-
-int test(double (*fp)(double y) )
-{
-   int i,x;
-
-   for (i = -100; i < 100; i++)
-   {  
-      fp(i);
-      if (errno)
-         total_err_count ++;
-   }
-
-  return total_err_count;
-}
-
-int main()
-{
-  int en1, en2;
-  double yy;
-  total_err_count = 0;
-  en1 = test(foo_opt);
-  total_err_count = 0;
-  en2 = test(foo);
-
-  if (en1 != en2)
-     abort();
-
-  return 0;
-
-}