#include "sched-int.h"
#include "cortex-a57-fma-steering.h"
#include "target-globals.h"
+#include "common/common-target.h"
/* This file should be included last. */
#include "target-def.h"
return SImode;
}
+#define PROBE_INTERVAL (1 << STACK_CHECK_PROBE_INTERVAL_EXP)
+
+/* We use the 12-bit shifted immediate arithmetic instructions so values
+ must be multiple of (1 << 12), i.e. 4096. */
+#define ARITH_FACTOR 4096
+
+#if (PROBE_INTERVAL % ARITH_FACTOR) != 0
+#error Cannot use simple address calculation for stack probing
+#endif
+
+/* The pair of scratch registers used for stack probing. */
+#define PROBE_STACK_FIRST_REG 9
+#define PROBE_STACK_SECOND_REG 10
+
+/* Emit code to probe a range of stack addresses from FIRST to FIRST+SIZE,
+ inclusive. These are offsets from the current stack pointer. */
+
+static void
+aarch64_emit_probe_stack_range (HOST_WIDE_INT first, HOST_WIDE_INT size)
+{
+ rtx reg1 = gen_rtx_REG (ptr_mode, PROBE_STACK_FIRST_REG);
+
+ /* See the same assertion on PROBE_INTERVAL above. */
+ gcc_assert ((first % ARITH_FACTOR) == 0);
+
+ /* See if we have a constant small number of probes to generate. If so,
+ that's the easy case. */
+ if (size <= PROBE_INTERVAL)
+ {
+ const HOST_WIDE_INT base = ROUND_UP (size, ARITH_FACTOR);
+
+ emit_set_insn (reg1,
+ plus_constant (ptr_mode,
+ stack_pointer_rtx, -(first + base)));
+ emit_stack_probe (plus_constant (ptr_mode, reg1, base - size));
+ }
+
+ /* The run-time loop is made up of 8 insns in the generic case while the
+ compile-time loop is made up of 4+2*(n-2) insns for n # of intervals. */
+ else if (size <= 4 * PROBE_INTERVAL)
+ {
+ HOST_WIDE_INT i, rem;
+
+ emit_set_insn (reg1,
+ plus_constant (ptr_mode,
+ stack_pointer_rtx,
+ -(first + PROBE_INTERVAL)));
+ emit_stack_probe (reg1);
+
+ /* Probe at FIRST + N * PROBE_INTERVAL for values of N from 2 until
+ it exceeds SIZE. If only two probes are needed, this will not
+ generate any code. Then probe at FIRST + SIZE. */
+ for (i = 2 * PROBE_INTERVAL; i < size; i += PROBE_INTERVAL)
+ {
+ emit_set_insn (reg1,
+ plus_constant (ptr_mode, reg1, -PROBE_INTERVAL));
+ emit_stack_probe (reg1);
+ }
+
+ rem = size - (i - PROBE_INTERVAL);
+ if (rem > 256)
+ {
+ const HOST_WIDE_INT base = ROUND_UP (rem, ARITH_FACTOR);
+
+ emit_set_insn (reg1, plus_constant (ptr_mode, reg1, -base));
+ emit_stack_probe (plus_constant (ptr_mode, reg1, base - rem));
+ }
+ else
+ emit_stack_probe (plus_constant (ptr_mode, reg1, -rem));
+ }
+
+ /* Otherwise, do the same as above, but in a loop. Note that we must be
+ extra careful with variables wrapping around because we might be at
+ the very top (or the very bottom) of the address space and we have
+ to be able to handle this case properly; in particular, we use an
+ equality test for the loop condition. */
+ else
+ {
+ rtx reg2 = gen_rtx_REG (ptr_mode, PROBE_STACK_SECOND_REG);
+
+ /* Step 1: round SIZE to the previous multiple of the interval. */
+
+ HOST_WIDE_INT rounded_size = size & -PROBE_INTERVAL;
+
+
+ /* Step 2: compute initial and final value of the loop counter. */
+
+ /* TEST_ADDR = SP + FIRST. */
+ emit_set_insn (reg1,
+ plus_constant (ptr_mode, stack_pointer_rtx, -first));
+
+ /* LAST_ADDR = SP + FIRST + ROUNDED_SIZE. */
+ emit_set_insn (reg2,
+ plus_constant (ptr_mode, stack_pointer_rtx,
+ -(first + rounded_size)));
+
+
+ /* Step 3: the loop
+
+ do
+ {
+ TEST_ADDR = TEST_ADDR + PROBE_INTERVAL
+ probe at TEST_ADDR
+ }
+ while (TEST_ADDR != LAST_ADDR)
+
+ probes at FIRST + N * PROBE_INTERVAL for values of N from 1
+ until it is equal to ROUNDED_SIZE. */
+
+ if (ptr_mode == DImode)
+ emit_insn (gen_probe_stack_range_di (reg1, reg1, reg2));
+ else
+ emit_insn (gen_probe_stack_range_si (reg1, reg1, reg2));
+
+
+ /* Step 4: probe at FIRST + SIZE if we cannot assert at compile-time
+ that SIZE is equal to ROUNDED_SIZE. */
+
+ if (size != rounded_size)
+ {
+ HOST_WIDE_INT rem = size - rounded_size;
+
+ if (rem > 256)
+ {
+ const HOST_WIDE_INT base = ROUND_UP (rem, ARITH_FACTOR);
+
+ emit_set_insn (reg2, plus_constant (ptr_mode, reg2, -base));
+ emit_stack_probe (plus_constant (ptr_mode, reg2, base - rem));
+ }
+ else
+ emit_stack_probe (plus_constant (ptr_mode, reg2, -rem));
+ }
+ }
+
+ /* Make sure nothing is scheduled before we are done. */
+ emit_insn (gen_blockage ());
+}
+
+/* Probe a range of stack addresses from REG1 to REG2 inclusive. These are
+ absolute addresses. */
+
+const char *
+aarch64_output_probe_stack_range (rtx reg1, rtx reg2)
+{
+ static int labelno = 0;
+ char loop_lab[32];
+ rtx xops[2];
+
+ ASM_GENERATE_INTERNAL_LABEL (loop_lab, "LPSRL", labelno++);
+
+ /* Loop. */
+ ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, loop_lab);
+
+ /* TEST_ADDR = TEST_ADDR + PROBE_INTERVAL. */
+ xops[0] = reg1;
+ xops[1] = GEN_INT (PROBE_INTERVAL);
+ output_asm_insn ("sub\t%0, %0, %1", xops);
+
+ /* Probe at TEST_ADDR. */
+ output_asm_insn ("str\txzr, [%0]", xops);
+
+ /* Test if TEST_ADDR == LAST_ADDR. */
+ xops[1] = reg2;
+ output_asm_insn ("cmp\t%0, %1", xops);
+
+ /* Branch. */
+ fputs ("\tb.ne\t", asm_out_file);
+ assemble_name_raw (asm_out_file, loop_lab);
+ fputc ('\n', asm_out_file);
+
+ return "";
+}
+
static bool
aarch64_frame_pointer_required (void)
{
if (flag_stack_usage_info)
current_function_static_stack_size = frame_size;
+ if (flag_stack_check == STATIC_BUILTIN_STACK_CHECK)
+ {
+ if (crtl->is_leaf && !cfun->calls_alloca)
+ {
+ if (frame_size > PROBE_INTERVAL && frame_size > STACK_CHECK_PROTECT)
+ aarch64_emit_probe_stack_range (STACK_CHECK_PROTECT,
+ frame_size - STACK_CHECK_PROTECT);
+ }
+ else if (frame_size > 0)
+ aarch64_emit_probe_stack_range (STACK_CHECK_PROTECT, frame_size);
+ }
+
/* Store pairs and load pairs have a range only -512 to 504. */
if (offset >= 512)
{
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