From d305ca88fc9b180a1790e02b144e921d17b393f0 Mon Sep 17 00:00:00 2001
From: Richard Sandiford <richard.sandiford@linaro.org>
Date: Wed, 30 Aug 2017 11:18:37 +0000
Subject: [PATCH] [59/77] Add a rtx_jump_table_data::get_data_mode helper
This patch adds a helper function to get the mode of the addresses
or offsets in a jump table. It also changes the final.c code to use
rtx_jump_table_data over rtx or rtx_insn in cases where it needed
to use the new helper. This in turn meant adding a safe_dyn_cast
equivalent of safe_as_a, to cope with null NEXT_INSNs.
2017-08-30 Richard Sandiford <richard.sandiford@linaro.org>
Alan Hayward <alan.hayward@arm.com>
David Sherwood <david.sherwood@arm.com>
gcc/
* is-a.h (safe_dyn_cast): New function.
* rtl.h (rtx_jump_table_data::get_data_mode): New function.
(jump_table_for_label): Likewise.
* final.c (final_addr_vec_align): Take an rtx_jump_table_data *
instead of an rtx_insn *.
(shorten_branches): Use dyn_cast instead of LABEL_P and
JUMP_TABLE_DATA_P. Use jump_table_for_label and
rtx_jump_table_data::get_data_mode.
(final_scan_insn): Likewise.
Co-Authored-By: Alan Hayward <alan.hayward@arm.com>
Co-Authored-By: David Sherwood <david.sherwood@arm.com>
From-SVN: r251511
---
gcc/ChangeLog | 14 +++++++++
gcc/final.c | 84 ++++++++++++++++++++++++---------------------------
gcc/is-a.h | 14 +++++++++
gcc/rtl.h | 19 ++++++++++++
4 files changed, 86 insertions(+), 45 deletions(-)
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 3fb54e6c82fb..612bd6922bd7 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,17 @@
+2017-08-30 Richard Sandiford <richard.sandiford@linaro.org>
+ Alan Hayward <alan.hayward@arm.com>
+ David Sherwood <david.sherwood@arm.com>
+
+ * is-a.h (safe_dyn_cast): New function.
+ * rtl.h (rtx_jump_table_data::get_data_mode): New function.
+ (jump_table_for_label): Likewise.
+ * final.c (final_addr_vec_align): Take an rtx_jump_table_data *
+ instead of an rtx_insn *.
+ (shorten_branches): Use dyn_cast instead of LABEL_P and
+ JUMP_TABLE_DATA_P. Use jump_table_for_label and
+ rtx_jump_table_data::get_data_mode.
+ (final_scan_insn): Likewise.
+
2017-08-30 Richard Sandiford <richard.sandiford@linaro.org>
Alan Hayward <alan.hayward@arm.com>
David Sherwood <david.sherwood@arm.com>
diff --git a/gcc/final.c b/gcc/final.c
index be41d6e10f0f..8af1f17886b3 100644
--- a/gcc/final.c
+++ b/gcc/final.c
@@ -219,9 +219,6 @@ static void leaf_renumber_regs (rtx_insn *);
#if HAVE_cc0
static int alter_cond (rtx);
#endif
-#ifndef ADDR_VEC_ALIGN
-static int final_addr_vec_align (rtx_insn *);
-#endif
static int align_fuzz (rtx, rtx, int, unsigned);
static void collect_fn_hard_reg_usage (void);
static tree get_call_fndecl (rtx_insn *);
@@ -518,9 +515,9 @@ default_jump_align_max_skip (rtx_insn *insn ATTRIBUTE_UNUSED)
#ifndef ADDR_VEC_ALIGN
static int
-final_addr_vec_align (rtx_insn *addr_vec)
+final_addr_vec_align (rtx_jump_table_data *addr_vec)
{
- int align = GET_MODE_SIZE (GET_MODE (PATTERN (addr_vec)));
+ int align = GET_MODE_SIZE (addr_vec->get_data_mode ());
if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
@@ -937,45 +934,41 @@ shorten_branches (rtx_insn *first)
if (INSN_P (insn))
continue;
- if (LABEL_P (insn))
+ if (rtx_code_label *label = dyn_cast <rtx_code_label *> (insn))
{
- rtx_insn *next;
- bool next_is_jumptable;
-
/* Merge in alignments computed by compute_alignments. */
- log = LABEL_TO_ALIGNMENT (insn);
+ log = LABEL_TO_ALIGNMENT (label);
if (max_log < log)
{
max_log = log;
- max_skip = LABEL_TO_MAX_SKIP (insn);
+ max_skip = LABEL_TO_MAX_SKIP (label);
}
- next = next_nonnote_insn (insn);
- next_is_jumptable = next && JUMP_TABLE_DATA_P (next);
- if (!next_is_jumptable)
+ rtx_jump_table_data *table = jump_table_for_label (label);
+ if (!table)
{
- log = LABEL_ALIGN (insn);
+ log = LABEL_ALIGN (label);
if (max_log < log)
{
max_log = log;
- max_skip = targetm.asm_out.label_align_max_skip (insn);
+ max_skip = targetm.asm_out.label_align_max_skip (label);
}
}
/* ADDR_VECs only take room if read-only data goes into the text
section. */
if ((JUMP_TABLES_IN_TEXT_SECTION
|| readonly_data_section == text_section)
- && next_is_jumptable)
+ && table)
{
- log = ADDR_VEC_ALIGN (next);
+ log = ADDR_VEC_ALIGN (table);
if (max_log < log)
{
max_log = log;
- max_skip = targetm.asm_out.label_align_max_skip (insn);
+ max_skip = targetm.asm_out.label_align_max_skip (label);
}
}
- LABEL_TO_ALIGNMENT (insn) = max_log;
- LABEL_TO_MAX_SKIP (insn) = max_skip;
+ LABEL_TO_ALIGNMENT (label) = max_log;
+ LABEL_TO_MAX_SKIP (label) = max_skip;
max_log = 0;
max_skip = 0;
}
@@ -1131,7 +1124,7 @@ shorten_branches (rtx_insn *first)
continue;
body = PATTERN (insn);
- if (JUMP_TABLE_DATA_P (insn))
+ if (rtx_jump_table_data *table = dyn_cast <rtx_jump_table_data *> (insn))
{
/* This only takes room if read-only data goes into the text
section. */
@@ -1139,7 +1132,7 @@ shorten_branches (rtx_insn *first)
|| readonly_data_section == text_section)
insn_lengths[uid] = (XVECLEN (body,
GET_CODE (body) == ADDR_DIFF_VEC)
- * GET_MODE_SIZE (GET_MODE (body)));
+ * GET_MODE_SIZE (table->get_data_mode ()));
/* Alignment is handled by ADDR_VEC_ALIGN. */
}
else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
@@ -1219,28 +1212,27 @@ shorten_branches (rtx_insn *first)
uid = INSN_UID (insn);
- if (LABEL_P (insn))
+ if (rtx_code_label *label = dyn_cast <rtx_code_label *> (insn))
{
- int log = LABEL_TO_ALIGNMENT (insn);
+ int log = LABEL_TO_ALIGNMENT (label);
#ifdef CASE_VECTOR_SHORTEN_MODE
/* If the mode of a following jump table was changed, we
may need to update the alignment of this label. */
- rtx_insn *next;
- bool next_is_jumptable;
-
- next = next_nonnote_insn (insn);
- next_is_jumptable = next && JUMP_TABLE_DATA_P (next);
- if ((JUMP_TABLES_IN_TEXT_SECTION
- || readonly_data_section == text_section)
- && next_is_jumptable)
+
+ if (JUMP_TABLES_IN_TEXT_SECTION
+ || readonly_data_section == text_section)
{
- int newlog = ADDR_VEC_ALIGN (next);
- if (newlog != log)
+ rtx_jump_table_data *table = jump_table_for_label (label);
+ if (table)
{
- log = newlog;
- LABEL_TO_ALIGNMENT (insn) = log;
- something_changed = 1;
+ int newlog = ADDR_VEC_ALIGN (table);
+ if (newlog != log)
+ {
+ log = newlog;
+ LABEL_TO_ALIGNMENT (insn) = log;
+ something_changed = 1;
+ }
}
}
#endif
@@ -1271,6 +1263,7 @@ shorten_branches (rtx_insn *first)
&& JUMP_TABLE_DATA_P (insn)
&& GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
{
+ rtx_jump_table_data *table = as_a <rtx_jump_table_data *> (insn);
rtx body = PATTERN (insn);
int old_length = insn_lengths[uid];
rtx_insn *rel_lab =
@@ -1366,13 +1359,14 @@ shorten_branches (rtx_insn *first)
max_addr - rel_addr, body);
if (!increasing
|| (GET_MODE_SIZE (vec_mode)
- >= GET_MODE_SIZE (GET_MODE (body))))
+ >= GET_MODE_SIZE (table->get_data_mode ())))
PUT_MODE (body, vec_mode);
if (JUMP_TABLES_IN_TEXT_SECTION
|| readonly_data_section == text_section)
{
insn_lengths[uid]
- = (XVECLEN (body, 1) * GET_MODE_SIZE (GET_MODE (body)));
+ = (XVECLEN (body, 1)
+ * GET_MODE_SIZE (table->get_data_mode ()));
insn_current_address += insn_lengths[uid];
if (insn_lengths[uid] != old_length)
something_changed = 1;
@@ -2191,6 +2185,7 @@ final_scan_insn (rtx_insn *insn, FILE *file, int optimize_p ATTRIBUTE_UNUSED,
rtx set;
#endif
rtx_insn *next;
+ rtx_jump_table_data *table;
insn_counter++;
@@ -2448,11 +2443,11 @@ final_scan_insn (rtx_insn *insn, FILE *file, int optimize_p ATTRIBUTE_UNUSED,
app_disable ();
- next = next_nonnote_insn (insn);
/* If this label is followed by a jump-table, make sure we put
the label in the read-only section. Also possibly write the
label and jump table together. */
- if (next != 0 && JUMP_TABLE_DATA_P (next))
+ table = jump_table_for_label (as_a <rtx_code_label *> (insn));
+ if (table)
{
#if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
/* In this case, the case vector is being moved by the
@@ -2467,7 +2462,7 @@ final_scan_insn (rtx_insn *insn, FILE *file, int optimize_p ATTRIBUTE_UNUSED,
(current_function_decl));
#ifdef ADDR_VEC_ALIGN
- log_align = ADDR_VEC_ALIGN (next);
+ log_align = ADDR_VEC_ALIGN (table);
#else
log_align = exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT);
#endif
@@ -2477,8 +2472,7 @@ final_scan_insn (rtx_insn *insn, FILE *file, int optimize_p ATTRIBUTE_UNUSED,
switch_to_section (current_function_section ());
#ifdef ASM_OUTPUT_CASE_LABEL
- ASM_OUTPUT_CASE_LABEL (file, "L", CODE_LABEL_NUMBER (insn),
- next);
+ ASM_OUTPUT_CASE_LABEL (file, "L", CODE_LABEL_NUMBER (insn), table);
#else
targetm.asm_out.internal_label (file, "L", CODE_LABEL_NUMBER (insn));
#endif
diff --git a/gcc/is-a.h b/gcc/is-a.h
index b4e5279514f6..2adc7409acbb 100644
--- a/gcc/is-a.h
+++ b/gcc/is-a.h
@@ -103,6 +103,11 @@ TYPE dyn_cast <TYPE> (pointer)
Note that we have converted two sets of assertions in the calls to varpool
into safe and efficient use of a variable.
+TYPE safe_dyn_cast <TYPE> (pointer)
+
+ Like dyn_cast <TYPE> (pointer), except that it accepts null pointers
+ and returns null results for them.
+
If you use these functions and get a 'inline function not defined' or a
'missing symbol' error message for 'is_a_helper<....>::test', it means that
@@ -222,4 +227,13 @@ dyn_cast (U *p)
return static_cast <T> (0);
}
+/* Similar to dyn_cast, except that the pointer may be null. */
+
+template <typename T, typename U>
+inline T
+safe_dyn_cast (U *p)
+{
+ return p ? dyn_cast <T> (p) : 0;
+}
+
#endif /* GCC_IS_A_H */
diff --git a/gcc/rtl.h b/gcc/rtl.h
index 8f4c1fa36f15..736134f5c522 100644
--- a/gcc/rtl.h
+++ b/gcc/rtl.h
@@ -634,6 +634,7 @@ public:
This method gets the underlying vec. */
inline rtvec get_labels () const;
+ inline scalar_int_mode get_data_mode () const;
};
class GTY(()) rtx_barrier : public rtx_insn
@@ -1477,6 +1478,24 @@ inline rtvec rtx_jump_table_data::get_labels () const
return XVEC (pat, 1); /* presumably an ADDR_DIFF_VEC */
}
+/* Return the mode of the data in the table, which is always a scalar
+ integer. */
+
+inline scalar_int_mode
+rtx_jump_table_data::get_data_mode () const
+{
+ return as_a <scalar_int_mode> (GET_MODE (PATTERN (this)));
+}
+
+/* If LABEL is followed by a jump table, return the table, otherwise
+ return null. */
+
+inline rtx_jump_table_data *
+jump_table_for_label (const rtx_code_label *label)
+{
+ return safe_dyn_cast <rtx_jump_table_data *> (NEXT_INSN (label));
+}
+
#define RTX_FRAME_RELATED_P(RTX) \
(RTL_FLAG_CHECK6 ("RTX_FRAME_RELATED_P", (RTX), DEBUG_INSN, INSN, \
CALL_INSN, JUMP_INSN, BARRIER, SET)->frame_related)
--
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