gcc/ChangeLog:
* config/riscv/riscv.cc (riscv_first_stack_step): make codes more
readable.
(riscv_expand_epilogue): likewise.
---
gcc/config/riscv/riscv.cc | 17 ++++++++++-------
1 file changed, 10 insertions(+), 7 deletions(-)
diff --git a/gcc/config/riscv/riscv.cc b/gcc/config/riscv/riscv.cc
index a50f2303032..95da08ffb3b 100644
--- a/gcc/config/riscv/riscv.cc
+++ b/gcc/config/riscv/riscv.cc
@@ -4926,8 +4926,11 @@ riscv_first_stack_step (struct riscv_frame_info *frame,
poly_int64 remaining_siz
if (SMALL_OPERAND (remaining_const_size))
return remaining_const_size;
+ poly_int64 callee_saved_first_step =
+ remaining_size - frame->frame_pointer_offset;
+ gcc_assert(callee_saved_first_step.is_constant ());
HOST_WIDE_INT min_first_step =
- riscv_stack_align ((remaining_size -
frame->frame_pointer_offset).to_constant());
+ riscv_stack_align (callee_saved_first_step.to_constant ());
HOST_WIDE_INT max_first_step = IMM_REACH / 2 - PREFERRED_STACK_BOUNDARY / 8;
HOST_WIDE_INT min_second_step = remaining_const_size - max_first_step;
gcc_assert (min_first_step <= max_first_step);
@@ -4935,7 +4938,7 @@ riscv_first_stack_step (struct riscv_frame_info *frame,
poly_int64 remaining_siz
/* As an optimization, use the least-significant bits of the total frame
size, so that the second adjustment step is just LUI + ADD. */
if (!SMALL_OPERAND (min_second_step)
- && remaining_const_size % IMM_REACH < IMM_REACH / 2
+ && remaining_const_size % IMM_REACH <= max_first_step
&& remaining_const_size % IMM_REACH >= min_first_step)
return remaining_const_size % IMM_REACH;
@@ -5129,14 +5132,14 @@ riscv_adjust_libcall_cfi_epilogue ()
void
riscv_expand_epilogue (int style)
{
- /* Split the frame into two. STEP1 is the amount of stack we should
- deallocate before restoring the registers. STEP2 is the amount we
- should deallocate afterwards.
+ /* Split the frame into 3 steps. STEP1 is the amount of stack we should
+ deallocate before restoring the registers. STEP2 is the amount we
+ should deallocate afterwards including the callee saved regs. STEP3
+ is the amount deallocated by save-restore libcall.
Start off by assuming that no registers need to be restored. */
struct riscv_frame_info *frame = &cfun->machine->frame;
unsigned mask = frame->mask;
- poly_int64 step1 = frame->total_size;
HOST_WIDE_INT step2 = 0;
bool use_restore_libcall = ((style == NORMAL_RETURN)
&& riscv_use_save_libcall (frame));
@@ -5223,7 +5226,7 @@ riscv_expand_epilogue (int style)
if (use_restore_libcall)
frame->mask = mask; /* Undo the above fib. */
- step1 -= step2 + libcall_size;
+ poly_int64 step1 = frame->total_size - step2 - libcall_size;
/* Set TARGET to BASE + STEP1. */
if (known_gt (step1, 0))
--
2.17.1
