From 39acb18f66f7b0ff8c36f5fa96e76168f959d2a1 Mon Sep 17 00:00:00 2001
From: Eric Botcazou <ebotcazou@adacore.com>
Date: Fri, 20 Aug 2010 21:22:16 +0000
Subject: [PATCH] aix.h (STACK_CHECK_STATIC_BUILTIN): Define to 1.
* config/rs6000/aix.h (STACK_CHECK_STATIC_BUILTIN): Define to 1.
* config/rs6000/linux.h (STACK_CHECK_STATIC_BUILTIN): Likewise.
* config/rs6000/linux64.h (STACK_CHECK_STATIC_BUILTIN): Likewise.
(STACK_CHECK_PROTECT): Define.
* config/rs6000/rs6000.c (rs6000_emit_probe_stack_range): New function.
(output_probe_stack_range): Likewise.
(rs6000_emit_prologue): Invoke rs6000_emit_probe_stack_range if static
builtin stack checking is enabled.
* config/rs6000/rs6000-protos.h (output_probe_stack_range): Declare.
* config/rs6000/rs6000.md (UNSPECV_PROBE_STACK_RANGE): New constant.
(probe_stack_range): New insn.
From-SVN: r163424
---
gcc/ChangeLog | 14 ++++
gcc/config/rs6000/aix.h | 3 +
gcc/config/rs6000/linux.h | 3 +
gcc/config/rs6000/linux64.h | 6 ++
gcc/config/rs6000/rs6000-protos.h | 1 +
gcc/config/rs6000/rs6000.c | 134 ++++++++++++++++++++++++++++++
gcc/config/rs6000/rs6000.md | 10 +++
7 files changed, 171 insertions(+)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 9f7a8c587919..8a7634749100 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2010-08-20 Eric Botcazou <ebotcazou@adacore.com>
+
+ * config/rs6000/aix.h (STACK_CHECK_STATIC_BUILTIN): Define to 1.
+ * config/rs6000/linux.h (STACK_CHECK_STATIC_BUILTIN): Likewise.
+ * config/rs6000/linux64.h (STACK_CHECK_STATIC_BUILTIN): Likewise.
+ (STACK_CHECK_PROTECT): Define.
+ * config/rs6000/rs6000.c (rs6000_emit_probe_stack_range): New function.
+ (output_probe_stack_range): Likewise.
+ (rs6000_emit_prologue): Invoke rs6000_emit_probe_stack_range if static
+ builtin stack checking is enabled.
+ * config/rs6000/rs6000-protos.h (output_probe_stack_range): Declare.
+ * config/rs6000/rs6000.md (UNSPECV_PROBE_STACK_RANGE): New constant.
+ (probe_stack_range): New insn.
+
2010-08-20 H.J. Lu <hongjiu.lu@intel.com>
PR target/45336
diff --git a/gcc/config/rs6000/aix.h b/gcc/config/rs6000/aix.h
index ec7add4c2e64..a5eb89da171f 100644
--- a/gcc/config/rs6000/aix.h
+++ b/gcc/config/rs6000/aix.h
@@ -260,3 +260,6 @@
/* WINT_TYPE */
#define WINT_TYPE "int"
+
+/* Static stack checking is supported by means of probes. */
+#define STACK_CHECK_STATIC_BUILTIN 1
diff --git a/gcc/config/rs6000/linux.h b/gcc/config/rs6000/linux.h
index d41c0dc56ef5..c659a3eac476 100644
--- a/gcc/config/rs6000/linux.h
+++ b/gcc/config/rs6000/linux.h
@@ -130,3 +130,6 @@
#ifdef TARGET_DEFAULT_LONG_DOUBLE_128
#define RS6000_DEFAULT_LONG_DOUBLE_SIZE 128
#endif
+
+/* Static stack checking is supported by means of probes. */
+#define STACK_CHECK_STATIC_BUILTIN 1
diff --git a/gcc/config/rs6000/linux64.h b/gcc/config/rs6000/linux64.h
index 900570f2ea17..0e165ea7199a 100644
--- a/gcc/config/rs6000/linux64.h
+++ b/gcc/config/rs6000/linux64.h
@@ -573,3 +573,9 @@ extern enum rs6000_cmodel cmodel;
#ifdef TARGET_DEFAULT_LONG_DOUBLE_128
#define RS6000_DEFAULT_LONG_DOUBLE_SIZE 128
#endif
+
+/* Static stack checking is supported by means of probes. */
+#define STACK_CHECK_STATIC_BUILTIN 1
+
+/* The default value isn't sufficient in 64-bit mode. */
+#define STACK_CHECK_PROTECT (TARGET_64BIT ? 16 * 1024 : 12 * 1024)
diff --git a/gcc/config/rs6000/rs6000-protos.h b/gcc/config/rs6000/rs6000-protos.h
index 02377f298e5b..8708accd7eaf 100644
--- a/gcc/config/rs6000/rs6000-protos.h
+++ b/gcc/config/rs6000/rs6000-protos.h
@@ -95,6 +95,7 @@ extern void rs6000_emit_sCOND (enum machine_mode, rtx[]);
extern void rs6000_emit_cbranch (enum machine_mode, rtx[]);
extern char * output_cbranch (rtx, const char *, int, rtx);
extern char * output_e500_flip_gt_bit (rtx, rtx);
+extern const char * output_probe_stack_range (rtx, rtx);
extern rtx rs6000_emit_set_const (rtx, enum machine_mode, rtx, int);
extern int rs6000_emit_cmove (rtx, rtx, rtx, rtx);
extern int rs6000_emit_vector_cond_expr (rtx, rtx, rtx, rtx, rtx, rtx);
diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index 89e0127a479f..3928901cdd9a 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -18788,6 +18788,137 @@ rs6000_emit_allocate_stack (HOST_WIDE_INT size, rtx copy_reg)
GEN_INT (-size))));
}
+#define PROBE_INTERVAL (1 << STACK_CHECK_PROBE_INTERVAL_EXP)
+
+#if PROBE_INTERVAL > 32768
+#error Cannot use indexed addressing mode for stack probing
+#endif
+
+/* 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
+rs6000_emit_probe_stack_range (HOST_WIDE_INT first, HOST_WIDE_INT size)
+{
+ /* See if we have a constant small number of probes to generate. If so,
+ that's the easy case. */
+ if (first + size <= 32768)
+ {
+ HOST_WIDE_INT i;
+
+ /* Probe at FIRST + N * PROBE_INTERVAL for values of N from 1 until
+ it exceeds SIZE. If only one probe is needed, this will not
+ generate any code. Then probe at FIRST + SIZE. */
+ for (i = PROBE_INTERVAL; i < size; i += PROBE_INTERVAL)
+ emit_stack_probe (plus_constant (stack_pointer_rtx, -(first + i)));
+
+ emit_stack_probe (plus_constant (stack_pointer_rtx, -(first + size)));
+ }
+
+ /* 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
+ {
+ HOST_WIDE_INT rounded_size;
+ rtx r12 = gen_rtx_REG (Pmode, 12);
+ rtx r0 = gen_rtx_REG (Pmode, 0);
+
+ /* Sanity check for the addressing mode we're going to use. */
+ gcc_assert (first <= 32768);
+
+ /* Step 1: round SIZE to the previous multiple of the interval. */
+
+ rounded_size = size & -PROBE_INTERVAL;
+
+
+ /* Step 2: compute initial and final value of the loop counter. */
+
+ /* TEST_ADDR = SP + FIRST. */
+ emit_insn (gen_rtx_SET (VOIDmode, r12,
+ plus_constant (stack_pointer_rtx, -first)));
+
+ /* LAST_ADDR = SP + FIRST + ROUNDED_SIZE. */
+ if (rounded_size > 32768)
+ {
+ emit_move_insn (r0, GEN_INT (-rounded_size));
+ emit_insn (gen_rtx_SET (VOIDmode, r0,
+ gen_rtx_PLUS (Pmode, r12, r0)));
+ }
+ else
+ emit_insn (gen_rtx_SET (VOIDmode, r0,
+ plus_constant (r12, -rounded_size)));
+
+
+ /* Step 3: the loop
+
+ while (TEST_ADDR != LAST_ADDR)
+ {
+ TEST_ADDR = TEST_ADDR + PROBE_INTERVAL
+ probe at TEST_ADDR
+ }
+
+ probes at FIRST + N * PROBE_INTERVAL for values of N from 1
+ until it is equal to ROUNDED_SIZE. */
+
+ if (TARGET_64BIT)
+ emit_insn (gen_probe_stack_rangedi (r12, r12, r0));
+ else
+ emit_insn (gen_probe_stack_rangesi (r12, r12, r0));
+
+
+ /* Step 4: probe at FIRST + SIZE if we cannot assert at compile-time
+ that SIZE is equal to ROUNDED_SIZE. */
+
+ if (size != rounded_size)
+ emit_stack_probe (plus_constant (r12, rounded_size - size));
+ }
+}
+
+/* Probe a range of stack addresses from REG1 to REG2 inclusive. These are
+ absolute addresses. */
+
+const char *
+output_probe_stack_range (rtx reg1, rtx reg2)
+{
+ static int labelno = 0;
+ char loop_lab[32], end_lab[32];
+ rtx xops[2];
+
+ ASM_GENERATE_INTERNAL_LABEL (loop_lab, "LPSRL", labelno);
+ ASM_GENERATE_INTERNAL_LABEL (end_lab, "LPSRE", labelno++);
+
+ ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, loop_lab);
+
+ /* Jump to END_LAB if TEST_ADDR == LAST_ADDR. */
+ xops[0] = reg1;
+ xops[1] = reg2;
+ if (TARGET_64BIT)
+ output_asm_insn ("{cmp|cmpd} 0,%0,%1", xops);
+ else
+ output_asm_insn ("{cmp|cmpw} 0,%0,%1", xops);
+
+ fputs ("\tbeq 0,", asm_out_file);
+ assemble_name_raw (asm_out_file, end_lab);
+ fputc ('\n', asm_out_file);
+
+ /* TEST_ADDR = TEST_ADDR + PROBE_INTERVAL. */
+ xops[1] = GEN_INT (-PROBE_INTERVAL);
+ output_asm_insn ("{cal %0,%1(%0)|addi %0,%0,%1}", xops);
+
+ /* Probe at TEST_ADDR and branch. */
+ output_asm_insn ("{st|stw} 0,0(%0)", xops);
+ fprintf (asm_out_file, "\tb ");
+ assemble_name_raw (asm_out_file, loop_lab);
+ fputc ('\n', asm_out_file);
+
+ ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, end_lab);
+
+ return "";
+}
+
/* Add to 'insn' a note which is PATTERN (INSN) but with REG replaced
with (plus:P (reg 1) VAL), and with REG2 replaced with RREG if REG2
is not NULL. It would be nice if dwarf2out_frame_debug_expr could
@@ -19400,6 +19531,9 @@ rs6000_emit_prologue (void)
&& call_used_regs[STATIC_CHAIN_REGNUM]);
HOST_WIDE_INT sp_offset = 0;
+ if (flag_stack_check == STATIC_BUILTIN_STACK_CHECK && info->total_size)
+ rs6000_emit_probe_stack_range (STACK_CHECK_PROTECT, info->total_size);
+
if (TARGET_FIX_AND_CONTINUE)
{
/* gdb on darwin arranges to forward a function from the old
diff --git a/gcc/config/rs6000/rs6000.md b/gcc/config/rs6000/rs6000.md
index 0ef7e98d9e53..c5e0ba1519b4 100644
--- a/gcc/config/rs6000/rs6000.md
+++ b/gcc/config/rs6000/rs6000.md
@@ -115,6 +115,7 @@
[(UNSPECV_BLOCK 0)
(UNSPECV_LL 1) ; load-locked
(UNSPECV_SC 2) ; store-conditional
+ (UNSPECV_PROBE_STACK_RANGE 3) ; probe range of stack addresses
(UNSPECV_EH_RR 9) ; eh_reg_restore
])
@@ -12663,6 +12664,15 @@
"{st%U0%X0|stw%U0%X0} 0,%0"
[(set_attr "type" "store")
(set_attr "length" "4")])
+
+(define_insn "probe_stack_range<P:mode>"
+ [(set (match_operand:P 0 "register_operand" "=r")
+ (unspec_volatile:P [(match_operand:P 1 "register_operand" "0")
+ (match_operand:P 2 "register_operand" "r")]
+ UNSPECV_PROBE_STACK_RANGE))]
+ ""
+ "* return output_probe_stack_range (operands[0], operands[2]);"
+ [(set_attr "type" "three")])
;; Compare insns are next. Note that the RS/6000 has two types of compares,
;; signed & unsigned, and one type of branch.
--
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