PR target/39118

	* config/i386/i386.c (expand_prologue): Emit blockage at the end
	of function prologue when frame pointer is used to access
	red zone area.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@144063 138bc75d-0d04-0410-961f-82ee72b054a4

2 files changed, 25 insertions, 8 deletions

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 7b385034640..c85a25697fb 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,10 @@
+2009-02-10  Uros Bizjak  <ubizjak@gmail.com>
+
+	PR target/39118
+	* config/i386/i386.c (expand_prologue): Emit blockage at the end
+	of function prologue when frame pointer is used to access
+	red zone area.
+
 2009-02-10  Richard Guenther  <rguenther@suse.de>
 
 	PR middle-end/39127
@@ -100,8 +107,7 @@
 
 2009-02-06  Nick Clifton  <nickc@redhat.com>
 
-	* config/m32c/m32c.h (PCC_BITFIELD_TYPE_MATTERS): Define to
-	zero.
+	* config/m32c/m32c.h (PCC_BITFIELD_TYPE_MATTERS): Define to zero.
 
 2009-02-06  Paolo Bonzini  <bonzini@gnu.org>
 
@@ -249,7 +255,7 @@
 
 2009-02-02  Catherine Moore  <clm@codesourcery.com>
 
-	* sde.h (SUBTARGET_ARM_SPEC): Don;t assemble -fpic code as -mabicalls.
+	* sde.h (SUBTARGET_ARM_SPEC): Don't assemble -fpic code as -mabicalls.
 
 2009-02-02  Richard Sandiford  <rdsandiford@googlemail.com>
 
@@ -444,8 +450,7 @@
 
 	* regclass.c: Rename reginfo.c.  Change file description.
 	(FORBIDDEN_INC_DEC_CLASSES): Remove.
-	(reg_class_superclasses, forbidden_inc_dec_class, in_inc_dec):
-	Remove.
+	(reg_class_superclasses, forbidden_inc_dec_class, in_inc_dec): Remove.
 	(init_reg_sets_1): Remove code for evaluation of
 	reg_class_superclasses and losing_caller_save_reg_set.
 	(init_regs): Remove init_reg_autoinc.
@@ -579,8 +584,7 @@
 2009-01-28  Jakub Jelinek  <jakub@redhat.com>
 
 	PR rtl-optimization/38740
-	* reorg.c (gate_handle_delay_slots): Avoid dbr scheduling
-	if !optimize.
+	* reorg.c (gate_handle_delay_slots): Avoid dbr scheduling if !optimize.
 	* config/mips/mips.c (mips_reorg): Likewise.
 
 2009-01-28  Richard Guenther  <rguenther@suse.de>
diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 7c25a187026..e64bcc65575 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -7997,6 +7997,7 @@ ix86_expand_prologue (void)
 {
   rtx insn;
   bool pic_reg_used;
+  bool emit_blockage = false;
   struct ix86_frame frame;
   HOST_WIDE_INT allocate;
 
@@ -8214,7 +8215,7 @@ ix86_expand_prologue (void)
     {
       if (pic_reg_used)
 	emit_insn (gen_prologue_use (pic_offset_table_rtx));
-      emit_insn (gen_blockage ());
+      emit_blockage = true;
     }
 
   if (crtl->drap_reg && !crtl->stack_realign_needed)
@@ -8227,6 +8228,18 @@ ix86_expand_prologue (void)
       insn = emit_insn (gen_rtx_SET (VOIDmode, crtl->drap_reg, x));
     }
 
+  /* Prevent instructions from being scheduled into register save push
+     sequence when access to the redzone area is done through frame pointer.
+     The offset betweeh the frame pointer and the stack pointer is calculated
+     relative to the value of the stack pointer at the end of the function
+     prologue, and moving instructions that access redzone area via frame
+     pointer inside push sequence violates this assumption.  */
+  if (frame_pointer_needed && frame.red_zone_size)
+    emit_blockage = true;
+
+  if (emit_blockage)
+    emit_insn (gen_blockage ()); 
+
   /* Emit cld instruction if stringops are used in the function.  */
   if (TARGET_CLD && ix86_current_function_needs_cld)
     emit_insn (gen_cld ());