From: Andi Kleen <a...@gcc.gnu.org>
gcc/ChangeLog:
* common.opt: Enable -fbit-tests and -fjump-tables only at -O1.
* tree-switch-conversion.h (jump_table_cluster::is_enabled):
Dito.
---
gcc/common.opt | 4 ++--
gcc/tree-switch-conversion.h | 5 +++--
2 files changed, 5 insertions(+), 4 deletions(-)
diff --git a/gcc/common.opt b/gcc/common.opt
index 12b25ff486de..4af7a94fea42 100644
--- a/gcc/common.opt
+++ b/gcc/common.opt
@@ -2189,11 +2189,11 @@ Common Var(flag_ivopts) Init(1) Optimization
Optimize induction variables on trees.
fjump-tables
-Common Var(flag_jump_tables) Init(1) Optimization
+Common Var(flag_jump_tables) Init(-1) Optimization
Use jump tables for sufficiently large switch statements.
fbit-tests
-Common Var(flag_bit_tests) Init(1) Optimization
+Common Var(flag_bit_tests) Init(-1) Optimization
Use bit tests for sufficiently large switch statements.
fkeep-inline-functions
diff --git a/gcc/tree-switch-conversion.h b/gcc/tree-switch-conversion.h
index 6468995eb316..fbfd7ff7b3ff 100644
--- a/gcc/tree-switch-conversion.h
+++ b/gcc/tree-switch-conversion.h
@@ -442,7 +442,7 @@ public:
/* Return whether bit test expansion is allowed. */
static inline bool is_enabled (void)
{
- return flag_bit_tests;
+ return flag_bit_tests >= 0 ? flag_bit_tests : (optimize >= 1);
}
/* True when the jump table handles an entire switch statement. */
@@ -524,7 +524,8 @@ bool jump_table_cluster::is_enabled (void)
over-ruled us, we really have no choice. */
if (!targetm.have_casesi () && !targetm.have_tablejump ())
return false;
- if (!flag_jump_tables)
+ int flag = flag_jump_tables >= 0 ? flag_jump_tables : (optimize >= 1);
+ if (!flag)
return false;
#ifndef ASM_OUTPUT_ADDR_DIFF_ELT
if (flag_pic)
--
2.46.2
