@@ -38,6 +38,7 @@ typedef enum { no_action, dec_before, inc_after } pdp11_action;
typedef enum { little, either, big } pdp11_partorder;
extern bool pdp11_expand_operands (rtx *, rtx [][2], int,
pdp11_action *, pdp11_partorder);
+extern int pdp11_sp_frame_offset (void);
extern int pdp11_initial_elimination_offset (int, int);
extern enum reg_class pdp11_regno_reg_class (int);
@@ -45,3 +46,5 @@ extern enum reg_class pdp11_regno_reg_class (int);
extern void output_ascii (FILE *, const char *, int);
extern void pdp11_asm_output_var (FILE *, const char *, int, int, bool);
+extern void pdp11_expand_prologue (void);
+extern void pdp11_expand_epilogue (void);
@@ -141,8 +141,6 @@ decode_pdp11_d (const struct real_format *fmt ATTRIBUTE_UNUSED,
static const char *singlemove_string (rtx *);
static bool pdp11_assemble_integer (rtx, unsigned int, int);
-static void pdp11_output_function_prologue (FILE *, HOST_WIDE_INT);
-static void pdp11_output_function_epilogue (FILE *, HOST_WIDE_INT);
static bool pdp11_rtx_costs (rtx, int, int, int *, bool);
static bool pdp11_return_in_memory (const_tree, const_tree);
static rtx pdp11_function_value (const_tree, const_tree, bool);
@@ -166,11 +164,6 @@ static bool pdp11_legitimate_constant_p (enum machine_mode, rtx);
#undef TARGET_ASM_INTEGER
#define TARGET_ASM_INTEGER pdp11_assemble_integer
-#undef TARGET_ASM_FUNCTION_PROLOGUE
-#define TARGET_ASM_FUNCTION_PROLOGUE pdp11_output_function_prologue
-#undef TARGET_ASM_FUNCTION_EPILOGUE
-#define TARGET_ASM_FUNCTION_EPILOGUE pdp11_output_function_epilogue
-
#undef TARGET_ASM_OPEN_PAREN
#define TARGET_ASM_OPEN_PAREN "["
#undef TARGET_ASM_CLOSE_PAREN
@@ -227,95 +220,92 @@ static bool pdp11_legitimate_constant_p (enum machine_mode, rtx);
#undef TARGET_LEGITIMATE_CONSTANT_P
#define TARGET_LEGITIMATE_CONSTANT_P pdp11_legitimate_constant_p
-/*
- stream is a stdio stream to output the code to.
- size is an int: how many units of temporary storage to allocate.
- Refer to the array `regs_ever_live' to determine which registers
- to save; `regs_ever_live[I]' is nonzero if register number I
- is ever used in the function. This macro is responsible for
- knowing which registers should not be saved even if used.
-*/
+/* A helper function to determine if REGNO should be saved in the
+ current function's stack frame. */
-static void
-pdp11_output_function_prologue (FILE *stream, HOST_WIDE_INT size)
-{
- HOST_WIDE_INT fsize = ((size) + 1) & ~1;
- int regno;
- int via_ac = -1;
+static inline bool
+pdp11_saved_regno (unsigned regno)
+{
+ return !call_used_regs[regno] && df_regs_ever_live_p (regno);
+}
- fprintf (stream,
- "\n\t; /* function prologue %s*/\n",
- current_function_name ());
+/* Expand the function prologue. */
- /* if we are outputting code for main,
- the switch FPU to right mode if TARGET_FPU */
- if (MAIN_NAME_P (DECL_NAME (current_function_decl)) && TARGET_FPU)
+void
+pdp11_expand_prologue (void)
+{
+ HOST_WIDE_INT fsize = get_frame_size ();
+ unsigned regno;
+ rtx x, via_ac = NULL;
+
+ /* If we are outputting code for main, the switch FPU to the
+ right mode if TARGET_FPU. */
+ if (MAIN_NAME_P (DECL_NAME (current_function_decl)) && TARGET_FPU)
{
- fprintf(stream,
- "\t;/* switch cpu to double float, single integer */\n");
- fprintf(stream, "\tsetd\n");
- fprintf(stream, "\tseti\n\n");
+ emit_insn (gen_setd ());
+ emit_insn (gen_seti ());
}
- if (frame_pointer_needed)
- {
- fprintf(stream, "\tmov r5, -(sp)\n");
- fprintf(stream, "\tmov sp, r5\n");
- }
- else
+ if (frame_pointer_needed)
{
- /* DON'T SAVE FP */
+ x = gen_rtx_PRE_DEC (Pmode, stack_pointer_rtx);
+ x = gen_frame_mem (Pmode, x);
+ emit_move_insn (x, hard_frame_pointer_rtx);
+
+ emit_move_insn (hard_frame_pointer_rtx, stack_pointer_rtx);
}
- /* make frame */
- if (fsize)
- asm_fprintf (stream, "\tsub $%#wo, sp\n", fsize);
-
- /* save CPU registers */
- for (regno = R0_REGNUM; regno <= PC_REGNUM; regno++)
- if (df_regs_ever_live_p (regno) && ! call_used_regs[regno])
- if (! ((regno == FRAME_POINTER_REGNUM)
- && frame_pointer_needed))
- fprintf (stream, "\tmov %s, -(sp)\n", reg_names[regno]);
- /* fpu regs saving */
-
- /* via_ac specifies the ac to use for saving ac4, ac5 */
- via_ac = -1;
-
- for (regno = AC0_REGNUM; regno <= AC5_REGNUM ; regno++)
+ /* Make frame. */
+ if (fsize)
{
- /* ac0 - ac3 */
- if (LOAD_FPU_REG_P(regno)
- && df_regs_ever_live_p (regno)
- && ! call_used_regs[regno])
- {
- fprintf (stream, "\tstd %s, -(sp)\n", reg_names[regno]);
- via_ac = regno;
- }
-
- /* maybe make ac4, ac5 call used regs?? */
- /* ac4 - ac5 */
- if (NO_LOAD_FPU_REG_P(regno)
- && df_regs_ever_live_p (regno)
- && ! call_used_regs[regno])
- {
- gcc_assert (via_ac != -1);
- fprintf (stream, "\tldd %s, %s\n",
- reg_names[regno], reg_names[via_ac]);
- fprintf (stream, "\tstd %s, -(sp)\n", reg_names[via_ac]);
- }
+ emit_insn (gen_addhi3 (stack_pointer_rtx, stack_pointer_rtx,
+ GEN_INT (-fsize)));
+
+ /* Prevent frame references via the frame pointer from being
+ scheduled before the frame is allocated. */
+ if (frame_pointer_needed)
+ emit_insn (gen_blockage ());
}
- fprintf (stream, "\t;/* end of prologue */\n\n");
+ /* Save CPU registers. */
+ for (regno = R0_REGNUM; regno <= PC_REGNUM; regno++)
+ if (pdp11_saved_regno (regno)
+ && (regno != HARD_FRAME_POINTER_REGNUM || !frame_pointer_needed))
+ {
+ x = gen_rtx_PRE_DEC (Pmode, stack_pointer_rtx);
+ x = gen_frame_mem (Pmode, x);
+ emit_move_insn (x, gen_rtx_REG (Pmode, regno));
+ }
+
+ /* Save FPU registers. */
+ for (regno = AC0_REGNUM; regno <= AC3_REGNUM; regno++)
+ if (pdp11_saved_regno (regno))
+ {
+ x = gen_rtx_PRE_DEC (Pmode, stack_pointer_rtx);
+ x = gen_frame_mem (DFmode, x);
+ via_ac = gen_rtx_REG (DFmode, regno);
+ emit_move_insn (x, via_ac);
+ }
+
+ /* ??? Maybe make ac4, ac5 call used regs?? */
+ for (regno = AC4_REGNUM; regno <= AC5_REGNUM; regno++)
+ if (pdp11_saved_regno (regno))
+ {
+ gcc_assert (via_ac != NULL);
+ emit_move_insn (via_ac, gen_rtx_REG (DFmode, regno));
+
+ x = gen_rtx_PRE_DEC (Pmode, stack_pointer_rtx);
+ x = gen_frame_mem (DFmode, x);
+ emit_move_insn (x, via_ac);
+ }
}
-/*
- The function epilogue should not depend on the current stack pointer!
+/* The function epilogue should not depend on the current stack pointer!
It should use the frame pointer only. This is mandatory because
of alloca; we also take advantage of it to omit stack adjustments
before returning. */
-/* maybe we can make leaf functions faster by switching to the
+/* Maybe we can make leaf functions faster by switching to the
second register file - this way we don't have to save regs!
leaf functions are ~ 50% of all functions (dynamically!)
@@ -328,109 +318,127 @@ pdp11_output_function_prologue (FILE *stream, HOST_WIDE_INT size)
maybe as option if you want to generate code for kernel mode? */
-static void
-pdp11_output_function_epilogue (FILE *stream, HOST_WIDE_INT size)
+void
+pdp11_expand_epilogue (void)
{
- HOST_WIDE_INT fsize = ((size) + 1) & ~1;
- int i, j, k;
+ HOST_WIDE_INT fsize = get_frame_size ();
+ unsigned regno;
+ rtx x, reg, via_ac = NULL;
- int via_ac;
-
- fprintf (stream, "\n\t; /*function epilogue */\n");
+ if (pdp11_saved_regno (AC4_REGNUM) || pdp11_saved_regno (AC5_REGNUM))
+ {
+ /* Find a temporary with which to restore AC4/5. */
+ for (regno = AC0_REGNUM; regno <= AC3_REGNUM; regno++)
+ if (pdp11_saved_regno (regno))
+ {
+ via_ac = gen_rtx_REG (DFmode, regno);
+ break;
+ }
+ }
- if (frame_pointer_needed)
- {
- /* hope this is safe - m68k does it also .... */
- df_set_regs_ever_live (FRAME_POINTER_REGNUM, false);
-
- for (i = PC_REGNUM, j = 0 ; i >= 0 ; i--)
- if (df_regs_ever_live_p (i) && ! call_used_regs[i])
- j++;
-
- /* remember # of pushed bytes for CPU regs */
- k = 2*j;
-
- /* change fp -> r5 due to the compile error on libgcc2.c */
- for (i = PC_REGNUM ; i >= R0_REGNUM ; i--)
- if (df_regs_ever_live_p (i) && ! call_used_regs[i])
- fprintf(stream, "\tmov %#" HOST_WIDE_INT_PRINT "o(r5), %s\n",
- (-fsize-2*j--)&0xffff, reg_names[i]);
-
- /* get ACs */
- via_ac = AC5_REGNUM;
-
- for (i = AC5_REGNUM; i >= AC0_REGNUM; i--)
- if (df_regs_ever_live_p (i) && ! call_used_regs[i])
- {
- via_ac = i;
- k += 8;
- }
-
- for (i = AC5_REGNUM; i >= AC0_REGNUM; i--)
- {
- if (LOAD_FPU_REG_P(i)
- && df_regs_ever_live_p (i)
- && ! call_used_regs[i])
- {
- fprintf(stream, "\tldd %#" HOST_WIDE_INT_PRINT "o(r5), %s\n",
- (-fsize-k)&0xffff, reg_names[i]);
- k -= 8;
- }
-
- if (NO_LOAD_FPU_REG_P(i)
- && df_regs_ever_live_p (i)
- && ! call_used_regs[i])
- {
- gcc_assert (LOAD_FPU_REG_P(via_ac));
-
- fprintf(stream, "\tldd %#" HOST_WIDE_INT_PRINT "o(r5), %s\n",
- (-fsize-k)&0xffff, reg_names[via_ac]);
- fprintf(stream, "\tstd %s, %s\n", reg_names[via_ac], reg_names[i]);
- k -= 8;
- }
- }
-
- fprintf(stream, "\tmov r5, sp\n");
- fprintf (stream, "\tmov (sp)+, r5\n");
- }
- else
- {
- via_ac = AC5_REGNUM;
-
- /* get ACs */
- for (i = AC5_REGNUM; i >= AC0_REGNUM; i--)
- if (df_regs_ever_live_p (i) && ! call_used_regs[i])
- via_ac = i;
-
- for (i = AC5_REGNUM; i >= AC0_REGNUM; i--)
+ /* If possible, restore registers via pops. */
+ if (!frame_pointer_needed || current_function_sp_is_unchanging)
+ {
+ /* Restore registers via pops. */
+
+ for (regno = AC5_REGNUM; regno >= AC0_REGNUM; regno--)
+ if (pdp11_saved_regno (regno))
+ {
+ x = gen_rtx_POST_INC (Pmode, stack_pointer_rtx);
+ x = gen_frame_mem (DFmode, x);
+ reg = gen_rtx_REG (DFmode, regno);
+
+ if (LOAD_FPU_REG_P (regno))
+ emit_move_insn (reg, x);
+ else
+ {
+ emit_move_insn (via_ac, x);
+ emit_move_insn (reg, via_ac);
+ }
+ }
+
+ for (regno = PC_REGNUM; regno >= R0_REGNUM + 2; regno--)
+ if (pdp11_saved_regno (regno)
+ && (regno != HARD_FRAME_POINTER_REGNUM || !frame_pointer_needed))
+ {
+ x = gen_rtx_POST_INC (Pmode, stack_pointer_rtx);
+ x = gen_frame_mem (Pmode, x);
+ emit_move_insn (gen_rtx_REG (Pmode, regno), x);
+ }
+ }
+ else
+ {
+ /* Restore registers via moves. */
+ /* ??? If more than a few registers need to be restored, it's smaller
+ to generate a pointer through which we can emit pops. Consider
+ that moves cost 2*NREG words and pops cost NREG+3 words. This
+ means that the crossover is NREG=3.
+
+ Possible registers to use are:
+ (1) The first call-saved general register. This register will
+ be restored with the last pop.
+ (2) R1, if it's not used as a return register.
+ (3) FP itself. This option may result in +4 words, since we
+ may need two add imm,rn instructions instead of just one.
+ This also has the downside that we're not representing
+ the unwind info in any way, so during the epilogue the
+ debugger may get lost. */
+
+ HOST_WIDE_INT ofs = -pdp11_sp_frame_offset ();
+
+ for (regno = AC5_REGNUM; regno >= AC0_REGNUM; regno--)
+ if (pdp11_saved_regno (regno))
+ {
+ x = plus_constant (hard_frame_pointer_rtx, ofs);
+ x = gen_frame_mem (DFmode, x);
+ reg = gen_rtx_REG (DFmode, regno);
+
+ if (LOAD_FPU_REG_P (regno))
+ emit_move_insn (reg, x);
+ else
+ {
+ emit_move_insn (via_ac, x);
+ emit_move_insn (reg, via_ac);
+ }
+ ofs += 8;
+ }
+
+ for (regno = PC_REGNUM; regno >= R0_REGNUM + 2; regno--)
+ if (pdp11_saved_regno (regno)
+ && (regno != HARD_FRAME_POINTER_REGNUM || !frame_pointer_needed))
+ {
+ x = plus_constant (hard_frame_pointer_rtx, ofs);
+ x = gen_frame_mem (Pmode, x);
+ emit_move_insn (gen_rtx_REG (Pmode, regno), x);
+ ofs += 2;
+ }
+ }
+
+ /* Deallocate the stack frame. */
+ if (fsize)
+ {
+ /* Prevent frame references via any pointer from being
+ scheduled after the frame is deallocated. */
+ emit_insn (gen_blockage ());
+
+ if (frame_pointer_needed)
{
- if (LOAD_FPU_REG_P(i)
- && df_regs_ever_live_p (i)
- && ! call_used_regs[i])
- fprintf(stream, "\tldd (sp)+, %s\n", reg_names[i]);
-
- if (NO_LOAD_FPU_REG_P(i)
- && df_regs_ever_live_p (i)
- && ! call_used_regs[i])
- {
- gcc_assert (LOAD_FPU_REG_P(via_ac));
-
- fprintf(stream, "\tldd (sp)+, %s\n", reg_names[via_ac]);
- fprintf(stream, "\tstd %s, %s\n", reg_names[via_ac], reg_names[i]);
- }
+ /* We can deallocate the frame with a single move. */
+ emit_move_insn (stack_pointer_rtx, hard_frame_pointer_rtx);
}
+ else
+ emit_insn (gen_addhi3 (stack_pointer_rtx, stack_pointer_rtx,
+ GEN_INT (fsize)));
+ }
- for (i = PC_REGNUM; i >= 0; i--)
- if (df_regs_ever_live_p (i) && !call_used_regs[i])
- fprintf(stream, "\tmov (sp)+, %s\n", reg_names[i]);
-
- if (fsize)
- fprintf((stream), "\tadd $%#" HOST_WIDE_INT_PRINT "o, sp\n",
- (fsize)&0xffff);
- }
-
- fprintf (stream, "\trts pc\n");
- fprintf (stream, "\t;/* end of epilogue*/\n\n\n");
+ if (frame_pointer_needed)
+ {
+ x = gen_rtx_POST_INC (Pmode, stack_pointer_rtx);
+ x = gen_frame_mem (Pmode, x);
+ emit_move_insn (hard_frame_pointer_rtx, x);
+ }
+
+ emit_jump_insn (gen_return ());
}
/* Return the best assembler insn template
@@ -1570,16 +1578,16 @@ pdp11_regno_reg_class (int regno)
}
-static int
+int
pdp11_sp_frame_offset (void)
{
int offset = 0, regno;
offset = get_frame_size();
for (regno = 0; regno <= PC_REGNUM; regno++)
- if (df_regs_ever_live_p (regno) && ! call_used_regs[regno])
+ if (pdp11_saved_regno (regno))
offset += 2;
for (regno = AC0_REGNUM; regno <= AC5_REGNUM; regno++)
- if (df_regs_ever_live_p (regno) && ! call_used_regs[regno])
+ if (pdp11_saved_regno (regno))
offset += 8;
return offset;
@@ -22,6 +22,13 @@
(include "predicates.md")
(include "constraints.md")
+(define_c_enum "unspecv"
+ [
+ UNSPECV_BLOCKAGE
+ UNSPECV_SETD
+ UNSPECV_SETI
+ ])
+
(define_constants
[
;; Register numbers
@@ -104,6 +111,50 @@
;; define function units
+;; Prologue and epilogue support.
+
+(define_expand "prologue"
+ [(const_int 0)]
+ ""
+{
+ pdp11_expand_prologue ();
+ DONE;
+})
+
+(define_expand "epilogue"
+ [(const_int 0)]
+ ""
+{
+ pdp11_expand_epilogue ();
+ DONE;
+})
+
+(define_expand "return"
+ [(return)]
+ "reload_completed && !frame_pointer_needed && pdp11_sp_frame_offset () == 0"
+ "")
+
+(define_insn "*rts"
+ [(return)]
+ ""
+ "rts pc")
+
+(define_insn "blockage"
+ [(unspec_volatile [(const_int 0)] UNSPECV_BLOCKAGE)]
+ ""
+ ""
+ [(set_attr "length" "0")])
+
+(define_insn "setd"
+ [(unspec_volatile [(const_int 0)] UNSPECV_SETD)]
+ ""
+ "setd")
+
+(define_insn "seti"
+ [(unspec_volatile [(const_int 0)] UNSPECV_SETI)]
+ ""
+ "seti")
+
;; arithmetic - values here immediately when next insn issued
;; or does it mean the number of cycles after this insn was issued?
;; how do I say that fpu insns use cpu also? (pre-interaction phase)