===================================================================
@@ -1644,6 +1644,12 @@ common_handle_option (struct gcc_options *opts,
: STACK_CHECK_STATIC_BUILTIN
? STATIC_BUILTIN_STACK_CHECK
: GENERIC_STACK_CHECK;
+ else if (!strcmp (arg, "indirect"))
+ /* This is an other stack checking method. */
+ opts->x_flag_stack_check = INDIRECT_STACK_CHECK;
+ else if (!strcmp (arg, "direct"))
+ /* This is an other stack checking method. */
+ opts->x_flag_stack_check = DIRECT_STACK_CHECK;
else
warning_at (loc, 0, "unknown stack check parameter \"%s\"", arg);
break;
===================================================================
@@ -153,7 +153,15 @@ enum stack_check_type
/* Check the stack and entirely rely on the target configuration
files, i.e. do not use the generic mechanism at all. */
- FULL_BUILTIN_STACK_CHECK
+ FULL_BUILTIN_STACK_CHECK,
+
+ /* Check the stack (if possible) before allocation of local variables at
+ each function entry. The stack limit is directly given e.g. by address
+ of a symbol */
+ DIRECT_STACK_CHECK,
+ /* Check the stack (if possible) before allocation of local variables at
+ each function entry. The stack limit is given by global variable. */
+ INDIRECT_STACK_CHECK
};
/* Names for the different levels of -Wstrict-overflow=N. The numeric
===================================================================
@@ -1386,7 +1386,12 @@ allocate_dynamic_stack_space (rtx size, unsigned s
/* If needed, check that we have the required amount of stack. Take into
account what has already been checked. */
- if (STACK_CHECK_MOVING_SP)
+ if ( STACK_CHECK_MOVING_SP
+#ifdef HAVE_generic_limit_check_stack
+ || crtl->limit_stack
+#endif
+ || flag_stack_check == DIRECT_STACK_CHECK
+ || flag_stack_check == INDIRECT_STACK_CHECK)
;
else if (flag_stack_check == GENERIC_STACK_CHECK)
probe_stack_range (STACK_OLD_CHECK_PROTECT + STACK_CHECK_MAX_FRAME_SIZE,
@@ -1423,19 +1428,32 @@ allocate_dynamic_stack_space (rtx size, unsigned s
/* Check stack bounds if necessary. */
if (crtl->limit_stack)
{
+ rtx limit_rtx;
rtx available;
rtx space_available = gen_label_rtx ();
+ if ( GET_CODE (stack_limit_rtx) == SYMBOL_REF
+ && flag_stack_check == INDIRECT_STACK_CHECK)
+ limit_rtx = expand_unop (Pmode, mov_optab,
+ gen_rtx_MEM (Pmode, stack_limit_rtx),
+ NULL_RTX, 1);
+ else
+ limit_rtx = stack_limit_rtx;
#ifdef STACK_GROWS_DOWNWARD
available = expand_binop (Pmode, sub_optab,
- stack_pointer_rtx, stack_limit_rtx,
+ stack_pointer_rtx, limit_rtx,
NULL_RTX, 1, OPTAB_WIDEN);
#else
available = expand_binop (Pmode, sub_optab,
- stack_limit_rtx, stack_pointer_rtx,
+ limit_rtx, stack_pointer_rtx,
NULL_RTX, 1, OPTAB_WIDEN);
#endif
emit_cmp_and_jump_insns (available, size, GEU, NULL_RTX, Pmode, 1,
space_available);
+#ifdef HAVE_stack_failure
+ if (HAVE_stack_failure)
+ emit_insn (gen_stack_failure ());
+ else
+#endif
#ifdef HAVE_trap
if (HAVE_trap)
emit_insn (gen_trap ());
@@ -1582,6 +1600,13 @@ probe_stack_range (HOST_WIDE_INT first, rtx size)
return;
}
#endif
+#ifdef HAVE_generic_limit_check_stack
+ else if (HAVE_generic_limit_check_stack)
+ {
+ rtx addr = memory_address (Pmode,stack_pointer_rtx);
+ emit_insn (gen_generic_limit_check_stack (addr));
+ }
+#endif
/* Otherwise we have to generate explicit probes. If we have a constant
small number of them to generate, that's the easy case. */
===================================================================
@@ -16285,6 +16285,307 @@ thumb_set_frame_pointer (arm_stack_offsets *offset
RTX_FRAME_RELATED_P (insn) = 1;
}
+/*search for possible work registers for stack-check operation at prologue
+ return the number of register that can be used without extra push/pop */
+
+static int
+stack_check_work_registers (rtx *workreg)
+{
+ int reg, i, k, n, nregs;
+
+ if (crtl->args.info.pcs_variant <= ARM_PCS_AAPCS_LOCAL)
+ {
+ nregs = crtl->args.info.aapcs_next_ncrn;
+ }
+ else
+ {
+ nregs = crtl->args.info.nregs;
+ }
+
+
+ n = 0;
+ i = 0;
+ /* check if we can use one of the argument registers r0..r3 as long as they
+ * not holding data*/
+ for (reg = 0; reg <= LAST_ARG_REGNUM && i < 2; reg++)
+ {
+ if ( !df_regs_ever_live_p (reg)
+ || (cfun->machine->uses_anonymous_args && crtl->args.pretend_args_size
+ > (LAST_ARG_REGNUM - reg) * UNITS_PER_WORD)
+ || (!cfun->machine->uses_anonymous_args && nregs < reg + 1)
+ )
+ {
+ workreg[i++] = gen_rtx_REG (SImode, reg);
+ /*if only one register can be used without push
+ *keep the next register in mind (either r1,r2,r3 or r0) that
+ *might be pushed later*/
+ if (i<2)
+ {
+ n = (reg + 1) % NUM_ARG_REGS;
+ }
+ }
+ }
+
+ /* otherwise try to use r4..r7*/
+ for (reg = LAST_ARG_REGNUM + 1; reg <= LAST_LO_REGNUM && i < 2; reg++)
+ {
+ if ( df_regs_ever_live_p (reg)
+ && !fixed_regs[reg]
+ && reg != FP_REGNUM )
+ {
+ workreg[i++] = gen_rtx_REG (SImode, reg);
+ }
+ }
+
+ if (TARGET_32BIT)
+ {
+ /* ARM and Thumb-2 can use high regs. */
+ for (reg = FIRST_HI_REGNUM; reg <= LAST_HI_REGNUM && i < 2; reg ++)
+ if ( df_regs_ever_live_p (reg)
+ && !fixed_regs[reg]
+ && reg != FP_REGNUM )
+ {
+ workreg[i++] = gen_rtx_REG (SImode, reg);
+ }
+ }
+
+ k = i;
+ /* if not enough found to be uses without extra push,
+ * collect next from r0..r3*/
+ for ( ; i<2; i++)
+ workreg[i] = gen_rtx_REG (SImode, n++);
+
+ /* only if k==0, two register will be pushed later
+ * only in this case the registers are guaranteed to be sorted */
+ return k;
+}
+
+/* push some registers to stack */
+static void
+emit_push_regs(int num_to_push, rtx *reg)
+{
+ int i;
+ rtvec tmpvec;
+ rtx par[16], dwarf, tmp, insn;
+
+ if (num_to_push > 15 || num_to_push < 0)
+ return;
+
+ tmpvec = gen_rtvec (1, reg[0]);
+ par[0] = gen_rtx_UNSPEC (BLKmode, tmpvec, UNSPEC_PUSH_MULT);
+ for (i=1; i<num_to_push; i++)
+ par[i] = gen_rtx_USE (VOIDmode, reg[i]);
+
+ tmp = plus_constant (stack_pointer_rtx, -4 * num_to_push);
+ dwarf = gen_rtx_SET (VOIDmode, stack_pointer_rtx, tmp);
+ tmp = gen_rtx_PRE_MODIFY (Pmode, stack_pointer_rtx, tmp);
+ tmp = gen_frame_mem (BLKmode, tmp);
+ par[0]= gen_rtx_SET (VOIDmode, tmp, par[0]);
+ tmp = gen_rtx_PARALLEL (VOIDmode, gen_rtvec_v (num_to_push, par));
+ insn = emit_insn (tmp);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ add_reg_note (insn, REG_FRAME_RELATED_EXPR, dwarf);
+ return;
+}
+
+/* pop some registers from stack */
+static void
+emit_pop_regs(const int num_to_pop, rtx *reg)
+{
+ int i;
+ rtvec tmpvec;
+ rtx par[16], dwarf, tmp, insn;
+
+ if (num_to_pop > 15 || num_to_pop < 0)
+ return;
+
+ tmpvec = gen_rtvec (1, reg[0]);
+ par[0] = gen_rtx_UNSPEC (BLKmode, tmpvec, UNSPEC_PUSH_MULT);
+ for (i=1; i<num_to_pop; i++)
+ par[i] = gen_rtx_USE (VOIDmode, reg[i]);
+ tmp = plus_constant (stack_pointer_rtx, 4 * num_to_pop);
+ dwarf = gen_rtx_SET (VOIDmode, stack_pointer_rtx, tmp);
+ tmp = gen_rtx_PRE_MODIFY (Pmode, stack_pointer_rtx, tmp);
+ tmp = gen_frame_mem (BLKmode, tmp);
+ par[0] = gen_rtx_SET (VOIDmode, tmp, par[0]);
+ tmp = gen_rtx_PARALLEL (VOIDmode, gen_rtvec_v (num_to_pop, par));
+ insn = emit_insn (tmp);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ add_reg_note (insn, REG_FRAME_RELATED_EXPR, dwarf);
+ return;
+}
+
+/*
+ * Emit RTL instructions for stack check at prologue stage.
+ * For Thumb this may look like this:
+ * push {rsym,ramn}
+ * ldr rsym, =symbol_addr_of(stack_limit_rtx)
+ * ldr rsym, [rsym]
+ * ldr ramn, =lenght_of(amount)
+ * add rsym, rsym, ramn
+ * cmp sp, rsym
+ * bhs .LSPCHK0
+ * push {lr}
+ * bl __thumb_stack_failure
+ * .LSPCHK0:
+ * pop {rsym,ramn}
+ */
+static void
+emit_stack_check_insns (HOST_WIDE_INT amount, int lr_not_yet_pushed)
+{
+ unsigned numregs;
+ unsigned amount_needsreg;
+ bool amount_const_ok, is_non_opt_thumb2, is_thumb2_hi_reg[2];
+ bool issym=false;
+ rtx reg[2], cmp_reg, amount_rtx;
+ rtx dwarf, tmp, insn;
+ rtx jump, label;
+
+ numregs = stack_check_work_registers(reg);
+
+ if (TARGET_THUMB1)
+ amount_const_ok = (amount < 256);
+ else
+ amount_const_ok = const_ok_for_arm (amount);
+
+ if (GET_CODE (stack_limit_rtx) == SYMBOL_REF) /*stack_limit_rtx*/
+ {
+ issym = true;
+ amount_needsreg = !amount_const_ok;
+ }
+ else
+ amount_needsreg = (amount != 0);
+
+ is_non_opt_thumb2 = (TARGET_THUMB2 && !(optimize_size || optimize >= 2));
+ is_thumb2_hi_reg[0] = (TARGET_THUMB2 && INTVAL(reg[0])>7);
+ is_thumb2_hi_reg[1] = (TARGET_THUMB2 && INTVAL(reg[1])>7);
+
+ /* push as many as needed */
+ if (issym && amount_needsreg) /*need two temp regs for limit and amount*/
+ {
+ if (numregs >= 2)
+ ; /*have 2 regs => no need to push*/
+ else if (numregs == 1)
+ {
+ /*have one reg but need two regs => push temp reg for amount*/
+ emit_push_regs (1, ®[1]); /*push {reg1}*/
+ /*due to additional push try to correct amount*/
+ if (amount >= 4)
+ amount -= 4;
+ }
+ else
+ {
+ /*have no reg but need two => push temp regs for limit and amount*/
+ emit_push_regs (2, ®[0]); /*push {reg0,reg1}*/
+ /*due to additional push try to correct amount*/
+ if (amount >= 8)
+ amount -= 8;
+ }
+ }
+ else if ((issym || amount_needsreg) && numregs == 0)
+ { /*push temp reg either for limit or amount*/
+ emit_push_regs (1, ®[0]); /*push {reg0}*/
+ /*due to additional push try to correct amount*/
+ if (amount >= 4)
+ {
+ if (amount_const_ok)
+ {
+ if (TARGET_THUMB1 || const_ok_for_arm(amount - 4))
+ amount -= 4;
+ /*on Thumb2 or ARM may not corrected; shouldn't hurt*/
+ }
+ else /*will be loaded from pool*/
+ amount -= 4;
+ }
+ }
+
+ amount_rtx = GEN_INT (amount);
+
+ /* move limit plus amount to cmp_reg e.g. reg[0] */
+ if (issym)
+ {
+ if (is_non_opt_thumb2 || is_thumb2_hi_reg[0])
+ arm_emit_movpair(reg[0], stack_limit_rtx);
+ else
+ emit_move_insn(reg[0], stack_limit_rtx);
+
+ if (flag_stack_check == INDIRECT_STACK_CHECK)
+ emit_insn (gen_movsi (reg[0], gen_rtx_MEM (SImode, reg[0])));
+ if (amount)
+ {
+ if (amount_const_ok)
+ emit_insn(gen_addsi3(reg[0], reg[0], amount_rtx));
+ else
+ {
+ if (is_non_opt_thumb2 || is_thumb2_hi_reg[1])
+ arm_emit_movpair(reg[1], amount_rtx);
+ else
+ emit_insn (gen_movsi (reg[1], amount_rtx));
+ emit_insn(gen_addsi3(reg[0], reg[0], reg[1]));
+ }
+ }
+ cmp_reg = reg[0];
+ }
+ else if (amount)
+ {
+ if (amount_const_ok)
+ emit_move_insn(reg[0], amount_rtx);
+ else
+ {
+ if (is_non_opt_thumb2 || is_thumb2_hi_reg[0])
+ arm_emit_movpair(reg[0], amount_rtx);
+ else
+ emit_insn (gen_movsi (reg[0], amount_rtx));
+ }
+ emit_insn(gen_addsi3(reg[0], reg[0], stack_limit_rtx));
+ cmp_reg = reg[0];
+ }
+ else
+ cmp_reg = stack_limit_rtx;
+
+ /*compare and jump*/
+ emit_insn (gen_blockage ());
+ label = gen_label_rtx ();
+ do_compare_rtx_and_jump (stack_pointer_rtx, cmp_reg, GEU, 1, Pmode,
+ NULL_RTX, NULL_RTX, label, -1);
+ jump = get_last_insn ();
+ gcc_assert (JUMP_P (jump));
+ JUMP_LABEL (jump) = label;
+ LABEL_NUSES (label)++;
+ if (lr_not_yet_pushed) /*push LR if not already done*/
+ {
+ rtx lr = gen_rtx_REG (SImode, LR_REGNUM);
+ emit_push_regs (1, &lr);
+ }
+ insn = emit_insn (gen_stack_failure ());
+ if (lr_not_yet_pushed)
+ {
+ /*the trap will not come back; but tell it has restored the stack*/
+ tmp = plus_constant (stack_pointer_rtx, 4);
+ dwarf = gen_rtx_SET (VOIDmode, stack_pointer_rtx, tmp);
+ RTX_FRAME_RELATED_P (insn) = 1;
+ add_reg_note (insn, REG_FRAME_RELATED_EXPR, dwarf);
+ }
+ emit_label (label);
+
+ /*restore registers*/
+ if (issym && amount_needsreg) /*pop temp regs used by limit and amount*/
+ {
+ if (numregs >= 2)
+ ; /*no need to pop*/
+ else if (numregs == 1)
+ emit_pop_regs (1, ®[1]); /*pop {reg1}*/
+ else
+ emit_pop_regs (2, ®[0]); /*pop {reg0, reg1}*/
+ }
+ else if ((issym || amount_needsreg) && numregs == 0)
+ { /*pop temp reg used by limit or amount*/
+ emit_pop_regs (1, ®[0]); /*pop {reg0}*/
+ }
+
+ return;
+}
+
/* Generate the prologue instructions for entry into an ARM or Thumb-2
function. */
void
@@ -16536,6 +16837,17 @@ arm_expand_prologue (void)
current_function_static_stack_size
= offsets->outgoing_args - offsets->saved_args;
+ if ( crtl->limit_stack
+ && !(IS_INTERRUPT (func_type))
+ && ( flag_stack_check == DIRECT_STACK_CHECK
+ || flag_stack_check == INDIRECT_STACK_CHECK)
+ && (offsets->outgoing_args - offsets->saved_args) > 0
+ )
+ {
+ emit_stack_check_insns (offsets->outgoing_args - saved_regs
+ - offsets->saved_args, !(live_regs_mask & (1<<LR_REGNUM)) );
+ }
+
if (offsets->outgoing_args != offsets->saved_args + saved_regs)
{
/* This add can produce multiple insns for a large constant, so we
@@ -21753,6 +22065,16 @@ thumb1_expand_prologue (void)
amount = offsets->outgoing_args - offsets->saved_regs;
amount -= 4 * thumb1_extra_regs_pushed (offsets, true);
+
+ if( crtl->limit_stack
+ && ( flag_stack_check == DIRECT_STACK_CHECK
+ || flag_stack_check == INDIRECT_STACK_CHECK)
+ && (offsets->outgoing_args - offsets->saved_args)
+ )
+ {
+ emit_stack_check_insns (amount, !(l_mask & (1<<LR_REGNUM)));
+ }
+
if (amount)
{
if (amount < 512)
@@ -21912,6 +22234,7 @@ thumb1_output_interwork (void)
asm_fprintf (f, "%s%U%s:\n", STUB_NAME, name);
return "";
+
}
/* Handle the case of a double word load into a low register from
===================================================================
@@ -112,6 +112,7 @@
UNSPEC_SYMBOL_OFFSET ; The offset of the start of the symbol from
; another symbolic address.
UNSPEC_MEMORY_BARRIER ; Represent a memory barrier.
+ UNSPEC_PROBE_STACK ; probe stack memory reference
UNSPEC_UNALIGNED_LOAD ; Used to represent ldr/ldrh instructions that access
; unaligned locations, on architectures which support
; that.
@@ -6908,8 +6909,8 @@
(define_insn "cbranchsi4_insn"
[(set (pc) (if_then_else
(match_operator 0 "arm_comparison_operator"
- [(match_operand:SI 1 "s_register_operand" "l,l*h")
- (match_operand:SI 2 "thumb1_cmp_operand" "lI*h,*r")])
+ [(match_operand:SI 1 "s_register_operand" "l,l*h,k")
+ (match_operand:SI 2 "thumb1_cmp_operand" "lI*h,*r,r")])
(label_ref (match_operand 3 "" ""))
(pc)))]
"TARGET_THUMB1"
@@ -7455,17 +7456,18 @@
(define_insn "*arm_cmpsi_insn"
[(set (reg:CC CC_REGNUM)
- (compare:CC (match_operand:SI 0 "s_register_operand" "l,r,r,r")
- (match_operand:SI 1 "arm_add_operand" "Py,r,rI,L")))]
+ (compare:CC (match_operand:SI 0 "s_register_operand" "l,r,k,r,r")
+ (match_operand:SI 1 "arm_add_operand" "Py,r,r,rI,L")))]
"TARGET_32BIT"
"@
cmp%?\\t%0, %1
cmp%?\\t%0, %1
cmp%?\\t%0, %1
+ cmp%?\\t%0, %1
cmn%?\\t%0, #%n1"
[(set_attr "conds" "set")
- (set_attr "arch" "t2,t2,any,any")
- (set_attr "length" "2,2,4,4")]
+ (set_attr "arch" "t2,t2,any,any,any")
+ (set_attr "length" "2,2,4,4,4")]
)
(define_insn "*cmpsi_shiftsi"
@@ -11180,6 +11182,69 @@
;;
+(define_expand "probe_stack"
+ [(match_operand 0 "memory_operand" "")]
+ "TARGET_EITHER"
+{
+ if ( flag_stack_check == DIRECT_STACK_CHECK
+ || flag_stack_check == INDIRECT_STACK_CHECK)
+ ;
+ else
+ {
+ emit_move_insn (operands[0], const0_rtx);
+ emit_insn (gen_probe_stack_done ());
+ emit_insn (gen_blockage ());
+ }
+ DONE;
+}
+)
+
+(define_insn "probe_stack_done"
+ [(unspec_volatile [(const_int 0)] UNSPEC_PROBE_STACK)]
+ "TARGET_EITHER"
+ {return \"@ probe stack done\";}
+ [(set_attr "type" "store1")
+ (set_attr "length" "0")]
+)
+
+(define_expand "generic_limit_check_stack"
+ [(match_operand 0 "memory_operand" "")]
+ "crtl->limit_stack
+ && flag_stack_check != DIRECT_STACK_CHECK
+ && flag_stack_check != INDIRECT_STACK_CHECK"
+{
+ rtx label = gen_label_rtx ();
+ rtx addr = copy_rtx (operands[0]);
+ addr = gen_rtx_fmt_ee (MINUS, Pmode, addr, GEN_INT (0));
+ addr = force_operand (addr, NULL_RTX);
+ emit_insn (gen_blockage ());
+ emit_cmp_and_jump_insns (stack_limit_rtx, addr, LEU, NULL_RTX, Pmode, 1,
+ label);
+ emit_insn (gen_stack_failure ());
+ emit_label (label);
+ emit_insn (gen_blockage ());
+ DONE;
+}
+)
+
+(define_insn "stack_failure"
+ [(trap_if (const_int 1) (const_int 0))
+ (clobber (reg:SI LR_REGNUM))
+ (clobber (reg:CC CC_REGNUM))]
+ "TARGET_EITHER"
+ "*
+ {
+ if (TARGET_ARM)
+ output_asm_insn (\"bl\\t__arm_stack_failure\\t%@ trap call\", operands);
+ else
+ output_asm_insn (\"bl\\t__thumb_stack_failure\\t%@ trap call\", operands);
+ }
+ return \"\";
+ "
+ [(set_attr "conds" "clob")
+ (set_attr "length" "8")]
+)
+
;; We only care about the lower 16 bits of the constant
;; being inserted into the upper 16 bits of the register.
(define_insn "*arm_movtas_ze"
ping references http://gcc.gnu.org/ml/gcc-patches/2011-09/msg00310.html http://gcc.gnu.org/ml/gcc-patches/2011-08/msg00216.html http://gcc.gnu.org/ml/gcc-patches/2011-07/msg00281.html http://gcc.gnu.org/ml/gcc-patches/2011-07/msg00149.html http://gcc.gnu.org/ml/gcc-patches/2011-06/msg01872.html http://gcc.gnu.org/ml/gcc-patches/2011-03/msg01226.html gcc/ChangeLog 2011-09-20 Thomas Klein <th.r.klein@web.de> * opts.c (common_handle_option): introduce new parameters "direct" and "indirect" * flag-types.h (enum stack_check_type): Likewise * explow.c (allocate_dynamic_stack_space): - suppress stack probing if parameter "direct", "indirect" or if a stack-limit is given - do additional read of limit value if parameter "indirect" and a stack-limit symbol is given - emit a call to a stack_failure function [as an alternative to a trap call] (function probe_stack_range): if allowed to override the range porbe emit generic_limit_check_stack * config/arm/arm.c (stack_check_work_registers): new function to find possible working registers [only used by "stack check"] (emit_push_regs): add push RTL instruction without keeping regnumber and frame memory in mind. (emit_pop_regs): add pop RTL instruction to revert the above push (emit_stack_check_insns): new function to write RTL instructions for stack check at prologue stage. (arm_expand_prologue): stack check integration for ARM and Thumb-2 (thumb1_output_function_prologue): stack check integration for Thumb-1 * config/arm/arm.md (cbranchsi4_insn): allow compare and branch using stack pointer register [at thumb mode] (arm_cmpsi_insn): allow comparing using stack pointer register [at arm] (probe_stack): do not emit code when parameters "direct" or "indirect" is given, emit move code way same as in gcc/explow.c [function emit_stack_probe] (probe_stack_done): dummy to make sure probe_stack insns are not optimized away (generic_limit_check_stack): if stack-limit and parameter "generic" is given use the limit the same way as in function allocate_dynamic_stack_space (stack_failure): failure call used in stack check functions emit_stack_check_insns, generic_limit_check_stack or allocate_dynamic_stack_space [similar to a trap but avoid conflict with builtin_trap]