expr.c (expand_expr, [...]): Do not replace an array element with the known initializ...

	* expr.c (expand_expr, case ARRAY_REF): Do not replace
	an array element with the known initializing value if it has
	side-effects.

	* toplev.c (rest_of_compilation): Remove dead code before
	purge_addressof.

From-SVN: r43120

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b21874bd148d14279b22940f67e84cac62ebbad0..3c0d4a524a20be5f41514da1f589bf9bd0a849b8 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,12 @@
+2001-06-09  Mark Mitchell  <mark@codesourcery.com>
+
+       * expr.c (expand_expr, case ARRAY_REF): Do not replace
+       an array element with the known initializing value if it has
+       side-effects.
+
+       * toplev.c (rest_of_compilation): Remove dead code before
+       purge_addressof.
+       
 2001-06-09  Neil Booth  <neil@daikokuya.demon.co.uk>
 
        * cppinit.c (print_help): Document -fpreprocessed.

diff --git a/gcc/expr.c b/gcc/expr.c
index 732b1108ddf2976da60022fb704e8023c7cdf740..a7b0ff4ff12a648f89d729d7fa68aa04f3ced0ba 100644 (file)
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -6891,7 +6891,7 @@ expand_expr (exp, target, tmode, modifier)
                         elem = TREE_CHAIN (elem))
                      ;
 
-                   if (elem)
+                   if (elem && !TREE_SIDE_EFFECTS (elem))
                      return expand_expr (fold (TREE_VALUE (elem)), target,
                                          tmode, ro_modifier);
                  }

diff --git a/gcc/toplev.c b/gcc/toplev.c
index 0e197cc2581de7ef80fa7d43947acaad50810ed5..2b75aa20a58a87d8c991b9eb75d88b94a0eccf9c 100644 (file)
--- a/gcc/toplev.c
+++ b/gcc/toplev.c
@@ -3031,6 +3031,16 @@ rest_of_compilation (decl)
          timevar_pop (TV_JUMP);
        }
 
+      /* It's important to remove dead code before we call
+        purge_addressof.  Sometimes, the only ADDRESSOFs for a REG
+        will be dead, and if we don't get rid of them, we will end up
+        committing ourselves to dumping the REG to the stack
+        unnecessarily.  */
+      find_basic_blocks (insns, max_reg_num (), rtl_dump_file);
+      cleanup_cfg ();
+      life_analysis (insns, rtl_dump_file, 
+                    PROP_SCAN_DEAD_CODE | PROP_KILL_DEAD_CODE);
+      
       /* The second pass of jump optimization is likely to have
          removed a bunch more instructions.  */
       renumber_insns (rtl_dump_file);