Re: [PATCH] gcc: remove 904-flatten-switch-stmt-00.patch

[Saul Wold <sgw@linux.intel.com>]

On 07/18/2012 11:03 AM, Bernhard Reutner-Fischer wrote:
> Remove brute-force flattening.
> Refer to -ftree-switch-conversion emit_case_bit_tests(),
> -ftree-if-to-switch-conversion et al in 4.8
>
> Signed-off-by: Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
> ---
>   meta/recipes-devtools/gcc/gcc-4.7.inc              |    1 -
>   .../gcc/gcc-4.7/904-flatten-switch-stmt-00.patch   |   76 --------------------
>   2 files changed, 77 deletions(-)
>   delete mode 100644 meta/recipes-devtools/gcc/gcc-4.7/904-flatten-switch-stmt-00.patch
>
Merged into OE-Core

Thanks
	Sau!
> diff --git a/meta/recipes-devtools/gcc/gcc-4.7.inc b/meta/recipes-devtools/gcc/gcc-4.7.inc
> index ece32c1..682cfa8 100644
> --- a/meta/recipes-devtools/gcc/gcc-4.7.inc
> +++ b/meta/recipes-devtools/gcc/gcc-4.7.inc
> @@ -52,7 +52,6 @@ SRC_URI = "git://github.com/mirrors/gcc.git;branch=${BRANCH};protocol=git \
>              file://306-libstdc++-namespace.patch  \
>              file://740-sh-pr24836.patch  \
>              file://800-arm-bigendian.patch  \
> -           file://904-flatten-switch-stmt-00.patch  \
>              file://arm-nolibfloat.patch  \
>              file://gcc-poison-system-directories.patch \
>              file://gcc-poison-dir-extend.patch \
> diff --git a/meta/recipes-devtools/gcc/gcc-4.7/904-flatten-switch-stmt-00.patch b/meta/recipes-devtools/gcc/gcc-4.7/904-flatten-switch-stmt-00.patch
> deleted file mode 100644
> index e790e06..0000000
> --- a/meta/recipes-devtools/gcc/gcc-4.7/904-flatten-switch-stmt-00.patch
> +++ /dev/null
> @@ -1,76 +0,0 @@
> -Upstream-Status: Pending
> -
> -Hi,
> -
> -The attached patch makes sure that we create smaller object code for
> -simple switch statements. We just make sure to flatten the switch
> -statement into an if-else chain, basically.
> -
> -This fixes a size-regression as compared to gcc-3.4, as can be seen
> -below.
> -
> -2007-04-15  Bernhard Fischer  <..>
> -
> -	* stmt.c (expand_case): Do not create a complex binary tree when
> -	optimizing for size but rather use the simple ordered list.
> -	(emit_case_nodes): do not emit jumps to the default_label when
> -	optimizing for size.
> -
> -Not regtested so far.
> -Comments?
> -
> -Attached is the test switch.c mentioned below.
> -
> -$ for i in 2.95 3.3 3.4 4.0 4.1 4.2.orig-HEAD 4.3.orig-HEAD 4.3-HEAD;do
> -gcc-$i  -DCHAIN -Os -o switch-CHAIN-$i.o -c switch.c ;done
> -$ for i in 2.95 3.3 3.4 4.0 4.1 4.2.orig-HEAD 4.3.orig-HEAD 4.3-HEAD;do
> -gcc-$i  -UCHAIN -Os -o switch-$i.o -c switch.c ;done
> -
> -$ size switch-*.o
> -   text	   data	    bss	    dec	    hex	filename
> -    169	      0	      0	    169	     a9	switch-2.95.o
> -    115	      0	      0	    115	     73	switch-3.3.o
> -    103	      0	      0	    103	     67	switch-3.4.o
> -    124	      0	      0	    124	     7c	switch-4.0.o
> -    124	      0	      0	    124	     7c	switch-4.1.o
> -    124	      0	      0	    124	     7c	switch-4.2.orig-HEAD.o
> -     95	      0	      0	     95	     5f	switch-4.3-HEAD.o
> -    124	      0	      0	    124	     7c	switch-4.3.orig-HEAD.o
> -    166	      0	      0	    166	     a6	switch-CHAIN-2.95.o
> -    111	      0	      0	    111	     6f	switch-CHAIN-3.3.o
> -     95	      0	      0	     95	     5f	switch-CHAIN-3.4.o
> -     95	      0	      0	     95	     5f	switch-CHAIN-4.0.o
> -     95	      0	      0	     95	     5f	switch-CHAIN-4.1.o
> -     95	      0	      0	     95	     5f	switch-CHAIN-4.2.orig-HEAD.o
> -     95	      0	      0	     95	     5f	switch-CHAIN-4.3-HEAD.o
> -     95	      0	      0	     95	     5f	switch-CHAIN-4.3.orig-HEAD.o
> -
> -
> -Content-Type: text/x-diff; charset=us-ascii
> -Content-Disposition: attachment; filename="gcc-4.3.gcc-flatten-switch-stmt.00.diff"
> -
> -Index: gcc-4_7-branch/gcc/stmt.c
> -===================================================================
> ---- gcc-4_7-branch.orig/gcc/stmt.c	2012-04-10 10:19:49.095337065 -0700
> -+++ gcc-4_7-branch/gcc/stmt.c	2012-04-10 10:32:52.219375048 -0700
> -@@ -2397,7 +2397,11 @@
> - 	     default code is emitted.  */
> -
> - 	  use_cost_table = estimate_case_costs (case_list);
> --	  balance_case_nodes (&case_list, NULL);
> -+	  /* When optimizing for size, we want a straight list to avoid
> -+	     jumps as much as possible. This basically creates an if-else
> -+	     chain.  */
> -+	  if (!optimize_size)
> -+	    balance_case_nodes (&case_list, NULL);
> - 	  emit_case_nodes (index, case_list, default_label, index_type);
> - 	  if (default_label)
> - 	    emit_jump (default_label);
> -@@ -2965,6 +2969,7 @@
> - 	    {
> - 	      if (!node_has_low_bound (node, index_type))
> - 		{
> -+		  if (!optimize_size) /* don't jl to the .default_label. */
> - 		  emit_cmp_and_jump_insns (index,
> - 					   convert_modes
> - 					   (mode, imode,
>