Fix issue with A stack negative offset

1 files changed, 54 insertions, 0 deletions

diff --git a/cgopt.c b/cgopt.c
index bf585b5..01a16c4 100644
--- a/cgopt.c
+++ b/cgopt.c
@@ -536,6 +536,37 @@ static void insert_decrement_b_stack_pointer (struct instruction *next_instructi
 }
 #endif
 
+#ifdef THUMB2
+static void insert_decrement_a_stack_pointer (struct instruction *next_instruction,int offset)
+{
+	struct instruction *previous_instruction,*instruction;
+
+	instruction=(struct instruction*)fast_memory_allocate (sizeof (struct instruction)+2*sizeof (struct parameter));
+
+	instruction->instruction_arity=2;
+	instruction->instruction_icode=ILEA;
+
+	instruction->instruction_parameters[0].parameter_type=P_INDIRECT;
+	instruction->instruction_parameters[0].parameter_offset=-offset;
+	instruction->instruction_parameters[0].parameter_data.reg.r=A_STACK_POINTER;
+
+	instruction->instruction_parameters[1].parameter_type=P_REGISTER;
+	instruction->instruction_parameters[1].parameter_data.i=A_STACK_POINTER;
+
+	previous_instruction=next_instruction->instruction_prev;
+	if (previous_instruction==NULL)
+		last_block->block_instructions=instruction;
+	else
+		previous_instruction->instruction_next=instruction;
+
+	instruction->instruction_next=next_instruction;
+	instruction->instruction_prev=previous_instruction;
+
+	if (next_instruction!=NULL)
+		next_instruction->instruction_prev=instruction;
+}
+#endif
+
 #if defined (I486) || defined (ARM)
 static void optimize_b_stack_access (struct parameter *parameter,struct instruction *instruction)
 {
@@ -787,6 +818,17 @@ void optimize_stack_access (struct basic_block *block,int *a_offset_p,int *b_off
 	previous_b_stack_parameter=NULL;
 # endif
 
+# ifdef THUMB2
+	int fix_a_offset=0;
+	if (*a_offset_p <= -256)
+	{
+		fix_a_offset=0-*a_offset_p;
+		insert_decrement_a_stack_pointer (block->block_instructions, fix_a_offset);
+		i_add_i_r (fix_a_offset, A_STACK_POINTER);
+		*a_offset_p=0;
+	}
+# endif
+
 	b_offset=0;
 	
 	compute_maximum_b_stack_offsets (*b_offset_p);
@@ -874,14 +916,26 @@ void optimize_stack_access (struct basic_block *block,int *a_offset_p,int *b_off
 	for_l (instruction,block->block_instructions,instruction_next){
 		if (instruction->instruction_icode==IMOVE){
 # ifdef ARM
+			if (*a_offset_p == -600)
+				fprintf(stderr, "%d, %d, %d, %d\n",
+						instruction->instruction_icode,
+						instruction->instruction_parameters[0].parameter_type,
+						instruction->instruction_parameters[0].parameter_data.reg.r,
+						instruction->instruction_parameters[0].parameter_offset);
 			if (instruction->instruction_parameters[1].parameter_type==P_INDIRECT &&
 				instruction->instruction_parameters[1].parameter_data.reg.r==A_STACK_POINTER)
 			{
+#  ifdef THUMB2
+				instruction->instruction_parameters[1].parameter_offset+=fix_a_offset;
+#  endif
 				previous_a_stack_parameter=&instruction->instruction_parameters[1];
 				previous_a_stack_parameter_icode=IMOVE;
 			} else if (instruction->instruction_parameters[0].parameter_type==P_INDIRECT &&
 					   instruction->instruction_parameters[0].parameter_data.reg.r==A_STACK_POINTER)
 			{
+#  ifdef THUMB2
+				instruction->instruction_parameters[0].parameter_offset+=fix_a_offset;
+#  endif
 				previous_a_stack_parameter=&instruction->instruction_parameters[0];
 				previous_a_stack_parameter_icode=IMOVE;
 			}