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[PATCH] alpha: Use TARGET_COMPUTE_FRAME_LAYOUT
- From: Richard Henderson <rth at twiddle dot net>
- To: gcc-patches at gcc dot gnu dot org
- Date: Mon, 9 Jul 2018 12:05:13 -0700
- Subject: [PATCH] alpha: Use TARGET_COMPUTE_FRAME_LAYOUT
At the same time, merge several related frame computing functions.
Recall that HWI is now always 64-bit, so merge IMASK and FMASK,
which allows merging of several loops within prologue and epilogue.
Full regression testing will take some time, but a quick browse
suggests no change in generated code.
r~
* config/alpha/alpha.c (direct_return): Move down after
struct machine_function definition; use saved frame_size;
return bool.
(struct machine_function): Add sa_mask, sa_size, frame_size.
(alpha_sa_mask, alpha_sa_size, compute_frame_size): Merge into ...
(alpha_compute_frame_layout): ... new function.
(TARGET_COMPUTE_FRAME_LAYOUT): New.
(alpha_initial_elimination_offset): Use saved sa_size.
(alpha_vms_initial_elimination_offset): Likewise.
(alpha_vms_can_eliminate): Remove alpha_sa_size call.
(alpha_expand_prologue): Use saved frame data. Merge integer
and fp register save loops.
(alpha_expand_epilogue): Likewise.
(alpha_start_function): Use saved frame data.
* config/alpha/alpha-protos.h (direct_return): Update.
(alpha_sa_size): Remove.
---
gcc/config/alpha/alpha-protos.h | 3 +-
gcc/config/alpha/alpha.c | 293 ++++++++++++--------------------
2 files changed, 109 insertions(+), 187 deletions(-)
diff --git a/gcc/config/alpha/alpha-protos.h b/gcc/config/alpha/alpha-protos.h
index d171f4eb414..099ce0e0c42 100644
--- a/gcc/config/alpha/alpha-protos.h
+++ b/gcc/config/alpha/alpha-protos.h
@@ -21,9 +21,8 @@ extern int alpha_next_sequence_number;
extern void literal_section (void);
extern int zap_mask (HOST_WIDE_INT);
-extern int direct_return (void);
+extern bool direct_return (void);
-extern int alpha_sa_size (void);
extern HOST_WIDE_INT alpha_initial_elimination_offset (unsigned int,
unsigned int);
extern void alpha_expand_prologue (void);
diff --git a/gcc/config/alpha/alpha.c b/gcc/config/alpha/alpha.c
index 9adfe159381..218306d3a07 100644
--- a/gcc/config/alpha/alpha.c
+++ b/gcc/config/alpha/alpha.c
@@ -728,19 +728,6 @@ alpha_vector_mode_supported_p (machine_mode mode)
return mode == V8QImode || mode == V4HImode || mode == V2SImode;
}
-/* Return 1 if this function can directly return via $26. */
-
-int
-direct_return (void)
-{
- return (TARGET_ABI_OSF
- && reload_completed
- && alpha_sa_size () == 0
- && get_frame_size () == 0
- && crtl->outgoing_args_size == 0
- && crtl->args.pretend_args_size == 0);
-}
-
/* Return the TLS model to use for SYMBOL. */
static enum tls_model
@@ -4837,6 +4824,10 @@ struct GTY(()) alpha_links;
struct GTY(()) machine_function
{
+ unsigned HOST_WIDE_INT sa_mask;
+ HOST_WIDE_INT sa_size;
+ HOST_WIDE_INT frame_size;
+
/* For flag_reorder_blocks_and_partition. */
rtx gp_save_rtx;
@@ -7236,83 +7227,59 @@ static int vms_save_fp_regno;
/* Register number used to reference objects off our PV. */
static int vms_base_regno;
-/* Compute register masks for saved registers. */
-
+/* Compute register masks for saved registers, register save area size,
+ and total frame size. */
static void
-alpha_sa_mask (unsigned long *imaskP, unsigned long *fmaskP)
+alpha_compute_frame_layout (void)
{
- unsigned long imask = 0;
- unsigned long fmask = 0;
- unsigned int i;
+ unsigned HOST_WIDE_INT sa_mask = 0;
+ HOST_WIDE_INT frame_size;
+ int sa_size;
/* When outputting a thunk, we don't have valid register life info,
but assemble_start_function wants to output .frame and .mask
directives. */
- if (cfun->is_thunk)
+ if (!cfun->is_thunk)
{
- *imaskP = 0;
- *fmaskP = 0;
- return;
- }
+ if (TARGET_ABI_OPEN_VMS && alpha_procedure_type == PT_STACK)
+ sa_mask |= HOST_WIDE_INT_1U << HARD_FRAME_POINTER_REGNUM;
- if (TARGET_ABI_OPEN_VMS && alpha_procedure_type == PT_STACK)
- imask |= (1UL << HARD_FRAME_POINTER_REGNUM);
+ /* One for every register we have to save. */
+ for (unsigned i = 0; i < FIRST_PSEUDO_REGISTER; i++)
+ if (! fixed_regs[i] && ! call_used_regs[i]
+ && df_regs_ever_live_p (i) && i != REG_RA)
+ sa_mask |= HOST_WIDE_INT_1U << i;
- /* One for every register we have to save. */
- for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
- if (! fixed_regs[i] && ! call_used_regs[i]
- && df_regs_ever_live_p (i) && i != REG_RA)
- {
- if (i < 32)
- imask |= (1UL << i);
- else
- fmask |= (1UL << (i - 32));
- }
-
- /* We need to restore these for the handler. */
- if (crtl->calls_eh_return)
- {
- for (i = 0; ; ++i)
+ /* We need to restore these for the handler. */
+ if (crtl->calls_eh_return)
{
- unsigned regno = EH_RETURN_DATA_REGNO (i);
- if (regno == INVALID_REGNUM)
- break;
- imask |= 1UL << regno;
+ for (unsigned i = 0; ; ++i)
+ {
+ unsigned regno = EH_RETURN_DATA_REGNO (i);
+ if (regno == INVALID_REGNUM)
+ break;
+ sa_mask |= HOST_WIDE_INT_1U << regno;
+ }
}
+
+ /* If any register spilled, then spill the return address also. */
+ /* ??? This is required by the Digital stack unwind specification
+ and isn't needed if we're doing Dwarf2 unwinding. */
+ if (sa_mask || alpha_ra_ever_killed ())
+ sa_mask |= HOST_WIDE_INT_1U << REG_RA;
}
- /* If any register spilled, then spill the return address also. */
- /* ??? This is required by the Digital stack unwind specification
- and isn't needed if we're doing Dwarf2 unwinding. */
- if (imask || fmask || alpha_ra_ever_killed ())
- imask |= (1UL << REG_RA);
-
- *imaskP = imask;
- *fmaskP = fmask;
-}
-
-int
-alpha_sa_size (void)
-{
- unsigned long mask[2];
- int sa_size = 0;
- int i, j;
-
- alpha_sa_mask (&mask[0], &mask[1]);
-
- for (j = 0; j < 2; ++j)
- for (i = 0; i < 32; ++i)
- if ((mask[j] >> i) & 1)
- sa_size++;
+ sa_size = popcount_hwi(sa_mask);
+ frame_size = get_frame_size ();
if (TARGET_ABI_OPEN_VMS)
{
/* Start with a stack procedure if we make any calls (REG_RA used), or
need a frame pointer, with a register procedure if we otherwise need
at least a slot, and with a null procedure in other cases. */
- if ((mask[0] >> REG_RA) & 1 || frame_pointer_needed)
+ if ((sa_mask >> REG_RA) & 1 || frame_pointer_needed)
alpha_procedure_type = PT_STACK;
- else if (get_frame_size() != 0)
+ else if (frame_size != 0)
alpha_procedure_type = PT_REGISTER;
else
alpha_procedure_type = PT_NULL;
@@ -7336,12 +7303,15 @@ alpha_sa_size (void)
/* If we want to copy PV into FP, we need to find some register
in which to save FP. */
-
vms_save_fp_regno = -1;
if (vms_base_regno == HARD_FRAME_POINTER_REGNUM)
- for (i = 0; i < 32; i++)
- if (! fixed_regs[i] && call_used_regs[i] && ! df_regs_ever_live_p (i))
- vms_save_fp_regno = i;
+ for (unsigned i = 0; i < 32; i++)
+ if (! fixed_regs[i] && call_used_regs[i]
+ && ! df_regs_ever_live_p (i))
+ {
+ vms_save_fp_regno = i;
+ break;
+ }
/* A VMS condition handler requires a stack procedure in our
implementation. (not required by the calling standard). */
@@ -7366,8 +7336,34 @@ alpha_sa_size (void)
if (sa_size & 1)
sa_size++;
}
+ sa_size *= 8;
- return sa_size * 8;
+ if (TARGET_ABI_OPEN_VMS)
+ frame_size = ALPHA_ROUND (sa_size
+ + (alpha_procedure_type == PT_STACK ? 8 : 0)
+ + frame_size
+ + crtl->args.pretend_args_size);
+ else
+ frame_size = (ALPHA_ROUND (crtl->outgoing_args_size)
+ + sa_size
+ + ALPHA_ROUND (frame_size + crtl->args.pretend_args_size));
+
+ cfun->machine->sa_mask = sa_mask;
+ cfun->machine->sa_size = sa_size;
+ cfun->machine->frame_size = frame_size;
+}
+
+#undef TARGET_COMPUTE_FRAME_LAYOUT
+#define TARGET_COMPUTE_FRAME_LAYOUT alpha_compute_frame_layout
+
+/* Return 1 if this function can directly return via $26. */
+
+bool
+direct_return (void)
+{
+ return (TARGET_ABI_OSF
+ && reload_completed
+ && cfun->machine->frame_size == 0);
}
/* Define the offset between two registers, one to be eliminated,
@@ -7379,7 +7375,7 @@ alpha_initial_elimination_offset (unsigned int from,
{
HOST_WIDE_INT ret;
- ret = alpha_sa_size ();
+ ret = cfun->machine->sa_size;
ret += ALPHA_ROUND (crtl->outgoing_args_size);
switch (from)
@@ -7407,9 +7403,6 @@ alpha_initial_elimination_offset (unsigned int from,
static bool
alpha_vms_can_eliminate (const int from ATTRIBUTE_UNUSED, const int to)
{
- /* We need the alpha_procedure_type to decide. Evaluate it now. */
- alpha_sa_size ();
-
switch (alpha_procedure_type)
{
case PT_NULL:
@@ -7439,7 +7432,7 @@ alpha_vms_initial_elimination_offset (unsigned int from, unsigned int to)
on the proper computations and will need the register save area size
in most cases. */
- HOST_WIDE_INT sa_size = alpha_sa_size ();
+ HOST_WIDE_INT sa_size = cfun->machine->sa_size;
/* PT_NULL procedures have no frame of their own and we only allow
elimination to the stack pointer. This is the argument pointer and we
@@ -7671,24 +7664,6 @@ emit_frame_store (unsigned int regno, rtx base_reg,
emit_frame_store_1 (reg, base_reg, frame_bias, base_ofs, reg);
}
-/* Compute the frame size. SIZE is the size of the "naked" frame
- and SA_SIZE is the size of the register save area. */
-
-static HOST_WIDE_INT
-compute_frame_size (HOST_WIDE_INT size, HOST_WIDE_INT sa_size)
-{
- if (TARGET_ABI_OPEN_VMS)
- return ALPHA_ROUND (sa_size
- + (alpha_procedure_type == PT_STACK ? 8 : 0)
- + size
- + crtl->args.pretend_args_size);
- else
- return ALPHA_ROUND (crtl->outgoing_args_size)
- + sa_size
- + ALPHA_ROUND (size
- + crtl->args.pretend_args_size);
-}
-
/* Write function prologue. */
/* On vms we have two kinds of functions:
@@ -7710,22 +7685,17 @@ void
alpha_expand_prologue (void)
{
/* Registers to save. */
- unsigned long imask = 0;
- unsigned long fmask = 0;
+ unsigned HOST_WIDE_INT sa_mask = cfun->machine->sa_mask;
/* Stack space needed for pushing registers clobbered by us. */
- HOST_WIDE_INT sa_size, sa_bias;
+ HOST_WIDE_INT sa_size = cfun->machine->sa_size;
/* Complete stack size needed. */
- HOST_WIDE_INT frame_size;
+ HOST_WIDE_INT frame_size = cfun->machine->frame_size;
/* Probed stack size; it additionally includes the size of
the "reserve region" if any. */
- HOST_WIDE_INT probed_size;
+ HOST_WIDE_INT probed_size, sa_bias;
/* Offset from base reg to register save area. */
HOST_WIDE_INT reg_offset;
rtx sa_reg;
- int i;
-
- sa_size = alpha_sa_size ();
- frame_size = compute_frame_size (get_frame_size (), sa_size);
if (flag_stack_usage_info)
current_function_static_stack_size = frame_size;
@@ -7735,8 +7705,6 @@ alpha_expand_prologue (void)
else
reg_offset = ALPHA_ROUND (crtl->outgoing_args_size);
- alpha_sa_mask (&imask, &fmask);
-
/* Emit an insn to reload GP, if needed. */
if (TARGET_ABI_OSF)
{
@@ -7875,29 +7843,15 @@ alpha_expand_prologue (void)
if (TARGET_ABI_OPEN_VMS && alpha_procedure_type == PT_STACK)
emit_frame_store (REG_PV, stack_pointer_rtx, 0, 0);
- /* Save register RA next. */
- if (imask & (1UL << REG_RA))
+ /* Save register RA next, followed by any other registers
+ that need to be saved. */
+ for (unsigned i = REG_RA; sa_mask != 0; i = ctz_hwi(sa_mask))
{
- emit_frame_store (REG_RA, sa_reg, sa_bias, reg_offset);
- imask &= ~(1UL << REG_RA);
+ emit_frame_store (i, sa_reg, sa_bias, reg_offset);
reg_offset += 8;
+ sa_mask &= ~(HOST_WIDE_INT_1U << i);
}
- /* Now save any other registers required to be saved. */
- for (i = 0; i < 31; i++)
- if (imask & (1UL << i))
- {
- emit_frame_store (i, sa_reg, sa_bias, reg_offset);
- reg_offset += 8;
- }
-
- for (i = 0; i < 31; i++)
- if (fmask & (1UL << i))
- {
- emit_frame_store (i+32, sa_reg, sa_bias, reg_offset);
- reg_offset += 8;
- }
-
if (TARGET_ABI_OPEN_VMS)
{
/* Register frame procedures save the fp. */
@@ -7984,14 +7938,11 @@ void
alpha_start_function (FILE *file, const char *fnname,
tree decl ATTRIBUTE_UNUSED)
{
- unsigned long imask = 0;
- unsigned long fmask = 0;
- /* Stack space needed for pushing registers clobbered by us. */
- HOST_WIDE_INT sa_size;
+ unsigned long imask, fmask;
/* Complete stack size needed. */
- unsigned HOST_WIDE_INT frame_size;
+ HOST_WIDE_INT frame_size = cfun->machine->frame_size;
/* The maximum debuggable frame size. */
- unsigned HOST_WIDE_INT max_frame_size = 1UL << 31;
+ const HOST_WIDE_INT max_frame_size = HOST_WIDE_INT_1 << 31;
/* Offset from base reg to register save area. */
HOST_WIDE_INT reg_offset;
char *entry_label = (char *) alloca (strlen (fnname) + 6);
@@ -8003,15 +7954,14 @@ alpha_start_function (FILE *file, const char *fnname,
#endif
alpha_fnname = fnname;
- sa_size = alpha_sa_size ();
- frame_size = compute_frame_size (get_frame_size (), sa_size);
if (TARGET_ABI_OPEN_VMS)
reg_offset = 8 + 8 * cfun->machine->uses_condition_handler;
else
reg_offset = ALPHA_ROUND (crtl->outgoing_args_size);
- alpha_sa_mask (&imask, &fmask);
+ imask = cfun->machine->sa_mask & 0xffffffffu;
+ fmask = cfun->machine->sa_mask >> 32;
/* Issue function start and label. */
if (TARGET_ABI_OPEN_VMS || !flag_inhibit_size_directive)
@@ -8078,7 +8028,7 @@ alpha_start_function (FILE *file, const char *fnname,
fprintf (file, "\t.frame $%d," HOST_WIDE_INT_PRINT_DEC ",$26,"
HOST_WIDE_INT_PRINT_DEC "\n",
vms_unwind_regno,
- frame_size >= (1UL << 31) ? 0 : frame_size,
+ frame_size >= max_frame_size ? 0 : frame_size,
reg_offset);
else if (!flag_inhibit_size_directive)
fprintf (file, "\t.frame $%d," HOST_WIDE_INT_PRINT_DEC ",$26,%d\n",
@@ -8158,12 +8108,11 @@ void
alpha_expand_epilogue (void)
{
/* Registers to save. */
- unsigned long imask = 0;
- unsigned long fmask = 0;
+ unsigned HOST_WIDE_INT sa_mask = cfun->machine->sa_mask;
/* Stack space needed for pushing registers clobbered by us. */
- HOST_WIDE_INT sa_size;
+ HOST_WIDE_INT sa_size = cfun->machine->sa_size;
/* Complete stack size needed. */
- HOST_WIDE_INT frame_size;
+ HOST_WIDE_INT frame_size = cfun->machine->frame_size;
/* Offset from base reg to register save area. */
HOST_WIDE_INT reg_offset;
int fp_is_frame_pointer, fp_offset;
@@ -8171,10 +8120,6 @@ alpha_expand_epilogue (void)
rtx sp_adj1, sp_adj2, mem, reg, insn;
rtx eh_ofs;
rtx cfa_restores = NULL_RTX;
- int i;
-
- sa_size = alpha_sa_size ();
- frame_size = compute_frame_size (get_frame_size (), sa_size);
if (TARGET_ABI_OPEN_VMS)
{
@@ -8186,8 +8131,6 @@ alpha_expand_epilogue (void)
else
reg_offset = ALPHA_ROUND (crtl->outgoing_args_size);
- alpha_sa_mask (&imask, &fmask);
-
fp_is_frame_pointer
= (TARGET_ABI_OPEN_VMS
? alpha_procedure_type == PT_STACK
@@ -8226,43 +8169,23 @@ alpha_expand_epilogue (void)
}
/* Restore registers in order, excepting a true frame pointer. */
-
- mem = gen_frame_mem (DImode, plus_constant (Pmode, sa_reg, reg_offset));
- reg = gen_rtx_REG (DImode, REG_RA);
- emit_move_insn (reg, mem);
- cfa_restores = alloc_reg_note (REG_CFA_RESTORE, reg, cfa_restores);
-
- reg_offset += 8;
- imask &= ~(1UL << REG_RA);
-
- for (i = 0; i < 31; ++i)
- if (imask & (1UL << i))
- {
- if (i == HARD_FRAME_POINTER_REGNUM && fp_is_frame_pointer)
- fp_offset = reg_offset;
- else
- {
- mem = gen_frame_mem (DImode,
- plus_constant (Pmode, sa_reg,
- reg_offset));
- reg = gen_rtx_REG (DImode, i);
- emit_move_insn (reg, mem);
- cfa_restores = alloc_reg_note (REG_CFA_RESTORE, reg,
- cfa_restores);
- }
- reg_offset += 8;
- }
-
- for (i = 0; i < 31; ++i)
- if (fmask & (1UL << i))
- {
- mem = gen_frame_mem (DFmode, plus_constant (Pmode, sa_reg,
- reg_offset));
- reg = gen_rtx_REG (DFmode, i+32);
- emit_move_insn (reg, mem);
- cfa_restores = alloc_reg_note (REG_CFA_RESTORE, reg, cfa_restores);
- reg_offset += 8;
- }
+ for (unsigned i = REG_RA; sa_mask != 0; i = ctz_hwi(sa_mask))
+ {
+ if (i == HARD_FRAME_POINTER_REGNUM && fp_is_frame_pointer)
+ fp_offset = reg_offset;
+ else
+ {
+ mem = gen_frame_mem (DImode,
+ plus_constant (Pmode, sa_reg,
+ reg_offset));
+ reg = gen_rtx_REG (DImode, i);
+ emit_move_insn (reg, mem);
+ cfa_restores = alloc_reg_note (REG_CFA_RESTORE, reg,
+ cfa_restores);
+ }
+ reg_offset += 8;
+ sa_mask &= ~(HOST_WIDE_INT_1U << i);
+ }
}
if (frame_size || eh_ofs)
--
2.17.1