From: Joseph Myers <joseph@codesourcery.com>
Date: Wed, 1 Jun 2005 18:19:09 +0000 (+0100)
Subject: common.opt (fjump-tables): New.
X-Git-Tag: misc/cutover-cvs2svn~2731
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=82c0180d7797e3602a7069dbf5696b487be5d7d8;p=thirdparty%2Fgcc.git

common.opt (fjump-tables): New.

	* common.opt (fjump-tables): New.
	* doc/invoke.texi (-fno-jump-tables): Document.
	* stmt.c (expand_end_case_type): Do not emit jump tables unless
	flag_jump_tables.

From-SVN: r100457
---

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 66269506c544..adfecf5de169 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2005-06-01  Joseph S. Myers  <joseph@codesourcery.com>
+
+	* common.opt (fjump-tables): New.
+	* doc/invoke.texi (-fno-jump-tables): Document.
+	* stmt.c (expand_end_case_type): Do not emit jump tables unless
+	flag_jump_tables.
+
 2005-06-01  Richard Earnshaw  <richard.earnshaw@arm.com>
 
 	* arm.md (bunordered, bordered, bungt, bunlt, bunge, bunle, buneq)
diff --git a/gcc/common.opt b/gcc/common.opt
index 91cc3c1ccc21..a603707508a4 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -488,6 +488,10 @@ fivopts
 Common Report Var(flag_ivopts) Init(1)
 Optimize induction variables on trees
 
+fjump-tables
+Common Var(flag_jump_tables) Init(1)
+Use jump tables for sufficiently large switch statements
+
 fkeep-inline-functions
 Common Report Var(flag_keep_inline_functions)
 Generate code for functions even if they are fully inlined
diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
index a6483e8eaa86..94c4b2ead7a7 100644
--- a/gcc/doc/invoke.texi
+++ b/gcc/doc/invoke.texi
@@ -732,6 +732,7 @@ See S/390 and zSeries Options.
 -finhibit-size-directive  -finstrument-functions @gol
 -fno-common  -fno-ident @gol
 -fpcc-struct-return  -fpic  -fPIC -fpie -fPIE @gol
+-fno-jump-tables @gol
 -freg-struct-return  -fshared-data  -fshort-enums @gol
 -fshort-double  -fshort-wchar @gol
 -fverbose-asm  -fpack-struct[=@var{n}]  -fstack-check @gol
@@ -12582,6 +12583,15 @@ generated position independent code can be only linked into executables.
 Usually these options are used when @option{-pie} GCC option will be
 used during linking.
 
+@item -fno-jump-tables
+@opindex fno-jump-tables
+Do not use jump tables for switch statements even where it would be
+more efficient than other code generation strategies.  This option is
+of use in conjunction with @option{-fpic} or @option{-fPIC} for
+building code which forms part of a dynamic linker and cannot
+reference the address of a jump table.  On some targets, jump tables
+do not require a GOT and this option is not needed.
+
 @item -ffixed-@var{reg}
 @opindex ffixed
 Treat the register named @var{reg} as a fixed register; generated code
diff --git a/gcc/stmt.c b/gcc/stmt.c
index d1e71dea4f15..6bdaf51b9db6 100644
--- a/gcc/stmt.c
+++ b/gcc/stmt.c
@@ -2458,6 +2458,7 @@ expand_case (tree exp)
 #ifndef ASM_OUTPUT_ADDR_DIFF_ELT
 	       || flag_pic
 #endif
+	       || !flag_jump_tables
 	       || TREE_CONSTANT (index_expr)
 	       /* If neither casesi or tablejump is available, we can
 		  only go this way.  */