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[Patch,AVR]: Fix PR52496: Add memory barriers to built-ins
- From: Georg-Johann Lay <avr at gjlay dot de>
- To: gcc-patches at gcc dot gnu dot org
- Cc: Denis Chertykov <chertykov at gmail dot com>, Eric Weddington <eric dot weddington at atmel dot com>
- Date: Wed, 07 Mar 2012 13:39:50 +0100
- Subject: [Patch,AVR]: Fix PR52496: Add memory barriers to built-ins
This patch adds memory barriers to
__builtin_avr_nop
__builtin_avr_sei
__builtin_avr_cli
__builtin_avr_wdr
__builtin_avr_sleep
__builtin_avr_delay_cycles
so that their code cannot be dragged over memory accesses.
Ok for trunk?
PR target/52496
* config/avr/avr.c (avr_mem_clobber): New static function.
(avr_expand_delay_cycles): Add memory clobber operand to
delay_cycles_1, delay_cycles_2, delay_cycles_3, delay_cycles_4.
* config/avr/avr.md (unspec): Add UNSPEC_MEMORY_BARRIER.
(enable_interrupt, disable_interrupt): New expander.
(nopv, sleep, wdr): New expanders.
(delay_cycles_1): Add memory clobber.
(delay_cycles_2): Add memory clobber.
(delay_cycles_3): Add memory clobber.
(delay_cycles_4): Add memory clobber.
(cli_sei): New insn from former "enable_interrupt",
"disable_interrupt" with memory clobber.
(*wdt): New insn from former "wdt" with memory clobber.
(*sleep): New insn from former "sleep" with memory clobber.
Index: config/avr/avr.md
===================================================================
--- config/avr/avr.md (revision 185031)
+++ config/avr/avr.md (working copy)
@@ -69,6 +69,7 @@ (define_c_enum "unspec"
UNSPEC_COPYSIGN
UNSPEC_IDENTITY
UNSPEC_INSERT_BITS
+ UNSPEC_MEMORY_BARRIER
])
(define_c_enum "unspecv"
@@ -5236,18 +5237,36 @@ (define_insn "popqi"
(set_attr "length" "1")])
;; Enable Interrupts
-(define_insn "enable_interrupt"
- [(unspec_volatile [(const_int 1)] UNSPECV_ENABLE_IRQS)]
+(define_expand "enable_interrupt"
+ [(clobber (const_int 0))]
""
- "sei"
- [(set_attr "length" "1")
- (set_attr "cc" "none")])
+ {
+ rtx mem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
+ MEM_VOLATILE_P (mem) = 1;
+ emit_insn (gen_cli_sei (const1_rtx, mem));
+ DONE;
+ })
;; Disable Interrupts
-(define_insn "disable_interrupt"
- [(unspec_volatile [(const_int 0)] UNSPECV_ENABLE_IRQS)]
+(define_expand "disable_interrupt"
+ [(clobber (const_int 0))]
""
- "cli"
+ {
+ rtx mem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
+ MEM_VOLATILE_P (mem) = 1;
+ emit_insn (gen_cli_sei (const0_rtx, mem));
+ DONE;
+ })
+
+(define_insn "cli_sei"
+ [(unspec_volatile [(match_operand:QI 0 "const_int_operand" "L,P")]
+ UNSPECV_ENABLE_IRQS)
+ (set (match_operand:BLK 1 "" "")
+ (unspec:BLK [(match_dup 1)] UNSPEC_MEMORY_BARRIER))]
+ ""
+ "@
+ cli
+ sei"
[(set_attr "length" "1")
(set_attr "cc" "none")])
@@ -5354,10 +5373,12 @@ (define_insn "delay_cycles_1"
[(unspec_volatile [(match_operand:QI 0 "const_int_operand" "n")
(const_int 1)]
UNSPECV_DELAY_CYCLES)
- (clobber (match_scratch:QI 1 "=&d"))]
+ (set (match_operand:BLK 1 "" "")
+ (unspec:BLK [(match_dup 1)] UNSPEC_MEMORY_BARRIER))
+ (clobber (match_scratch:QI 2 "=&d"))]
""
- "ldi %1,lo8(%0)
- 1: dec %1
+ "ldi %2,lo8(%0)
+ 1: dec %2
brne 1b"
[(set_attr "length" "3")
(set_attr "cc" "clobber")])
@@ -5366,11 +5387,13 @@ (define_insn "delay_cycles_2"
[(unspec_volatile [(match_operand:HI 0 "const_int_operand" "n")
(const_int 2)]
UNSPECV_DELAY_CYCLES)
- (clobber (match_scratch:HI 1 "=&w"))]
- ""
- "ldi %A1,lo8(%0)
- ldi %B1,hi8(%0)
- 1: sbiw %A1,1
+ (set (match_operand:BLK 1 "" "")
+ (unspec:BLK [(match_dup 1)] UNSPEC_MEMORY_BARRIER))
+ (clobber (match_scratch:HI 2 "=&w"))]
+ ""
+ "ldi %A2,lo8(%0)
+ ldi %B2,hi8(%0)
+ 1: sbiw %A2,1
brne 1b"
[(set_attr "length" "4")
(set_attr "cc" "clobber")])
@@ -5379,16 +5402,18 @@ (define_insn "delay_cycles_3"
[(unspec_volatile [(match_operand:SI 0 "const_int_operand" "n")
(const_int 3)]
UNSPECV_DELAY_CYCLES)
- (clobber (match_scratch:QI 1 "=&d"))
+ (set (match_operand:BLK 1 "" "")
+ (unspec:BLK [(match_dup 1)] UNSPEC_MEMORY_BARRIER))
(clobber (match_scratch:QI 2 "=&d"))
- (clobber (match_scratch:QI 3 "=&d"))]
+ (clobber (match_scratch:QI 3 "=&d"))
+ (clobber (match_scratch:QI 4 "=&d"))]
""
- "ldi %1,lo8(%0)
- ldi %2,hi8(%0)
- ldi %3,hlo8(%0)
- 1: subi %1,1
- sbci %2,0
+ "ldi %2,lo8(%0)
+ ldi %3,hi8(%0)
+ ldi %4,hlo8(%0)
+ 1: subi %2,1
sbci %3,0
+ sbci %4,0
brne 1b"
[(set_attr "length" "7")
(set_attr "cc" "clobber")])
@@ -5397,19 +5422,21 @@ (define_insn "delay_cycles_4"
[(unspec_volatile [(match_operand:SI 0 "const_int_operand" "n")
(const_int 4)]
UNSPECV_DELAY_CYCLES)
- (clobber (match_scratch:QI 1 "=&d"))
+ (set (match_operand:BLK 1 "" "")
+ (unspec:BLK [(match_dup 1)] UNSPEC_MEMORY_BARRIER))
(clobber (match_scratch:QI 2 "=&d"))
(clobber (match_scratch:QI 3 "=&d"))
- (clobber (match_scratch:QI 4 "=&d"))]
+ (clobber (match_scratch:QI 4 "=&d"))
+ (clobber (match_scratch:QI 5 "=&d"))]
""
- "ldi %1,lo8(%0)
- ldi %2,hi8(%0)
- ldi %3,hlo8(%0)
- ldi %4,hhi8(%0)
- 1: subi %1,1
- sbci %2,0
+ "ldi %2,lo8(%0)
+ ldi %3,hi8(%0)
+ ldi %4,hlo8(%0)
+ ldi %5,hhi8(%0)
+ 1: subi %2,1
sbci %3,0
sbci %4,0
+ sbci %5,0
brne 1b"
[(set_attr "length" "9")
(set_attr "cc" "clobber")])
@@ -5795,9 +5822,22 @@ (define_insn "*bswapsi2.libgcc"
;; CPU instructions
;; NOP taking 1 or 2 Ticks
-(define_insn "nopv"
+(define_expand "nopv"
+ [(parallel [(unspec_volatile [(match_operand:SI 0 "const_int_operand" "")]
+ UNSPECV_NOP)
+ (set (match_dup 1)
+ (unspec:BLK [(match_dup 1)] UNSPEC_MEMORY_BARRIER))])]
+ ""
+ {
+ operands[1] = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
+ MEM_VOLATILE_P (operands[1]) = 1;
+ })
+
+(define_insn "*nopv"
[(unspec_volatile [(match_operand:SI 0 "const_int_operand" "P,K")]
- UNSPECV_NOP)]
+ UNSPECV_NOP)
+ (set (match_operand:BLK 1 "" "")
+ (unspec:BLK [(match_dup 1)] UNSPEC_MEMORY_BARRIER))]
""
"@
nop
@@ -5806,16 +5846,40 @@ (define_insn "nopv"
(set_attr "cc" "none")])
;; SLEEP
-(define_insn "sleep"
- [(unspec_volatile [(const_int 0)] UNSPECV_SLEEP)]
+(define_expand "sleep"
+ [(parallel [(unspec_volatile [(const_int 0)] UNSPECV_SLEEP)
+ (set (match_dup 0)
+ (unspec:BLK [(match_dup 0)] UNSPEC_MEMORY_BARRIER))])]
+ ""
+ {
+ operands[0] = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
+ MEM_VOLATILE_P (operands[0]) = 1;
+ })
+
+(define_insn "*sleep"
+ [(unspec_volatile [(const_int 0)] UNSPECV_SLEEP)
+ (set (match_operand:BLK 0 "" "")
+ (unspec:BLK [(match_dup 0)] UNSPEC_MEMORY_BARRIER))]
""
"sleep"
[(set_attr "length" "1")
(set_attr "cc" "none")])
;; WDR
-(define_insn "wdr"
- [(unspec_volatile [(const_int 0)] UNSPECV_WDR)]
+(define_expand "wdr"
+ [(parallel [(unspec_volatile [(const_int 0)] UNSPECV_WDR)
+ (set (match_dup 0)
+ (unspec:BLK [(match_dup 0)] UNSPEC_MEMORY_BARRIER))])]
+ ""
+ {
+ operands[0] = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
+ MEM_VOLATILE_P (operands[0]) = 1;
+ })
+
+(define_insn "*wdr"
+ [(unspec_volatile [(const_int 0)] UNSPECV_WDR)
+ (set (match_operand:BLK 0 "" "")
+ (unspec:BLK [(match_dup 0)] UNSPEC_MEMORY_BARRIER))]
""
"wdr"
[(set_attr "length" "1")
Index: config/avr/avr.c
===================================================================
--- config/avr/avr.c (revision 185032)
+++ config/avr/avr.c (working copy)
@@ -9973,6 +9973,14 @@ avr_out_movmem (rtx insn ATTRIBUTE_UNUSE
/* Helper for __builtin_avr_delay_cycles */
+static rtx
+avr_mem_clobber (void)
+{
+ rtx mem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
+ MEM_VOLATILE_P (mem) = 1;
+ return mem;
+}
+
static void
avr_expand_delay_cycles (rtx operands0)
{
@@ -9984,7 +9992,8 @@ avr_expand_delay_cycles (rtx operands0)
{
loop_count = ((cycles - 9) / 6) + 1;
cycles_used = ((loop_count - 1) * 6) + 9;
- emit_insn (gen_delay_cycles_4 (gen_int_mode (loop_count, SImode)));
+ emit_insn (gen_delay_cycles_4 (gen_int_mode (loop_count, SImode),
+ avr_mem_clobber()));
cycles -= cycles_used;
}
@@ -9994,7 +10003,8 @@ avr_expand_delay_cycles (rtx operands0)
if (loop_count > 0xFFFFFF)
loop_count = 0xFFFFFF;
cycles_used = ((loop_count - 1) * 5) + 7;
- emit_insn (gen_delay_cycles_3 (gen_int_mode (loop_count, SImode)));
+ emit_insn (gen_delay_cycles_3 (gen_int_mode (loop_count, SImode),
+ avr_mem_clobber()));
cycles -= cycles_used;
}
@@ -10004,7 +10014,8 @@ avr_expand_delay_cycles (rtx operands0)
if (loop_count > 0xFFFF)
loop_count = 0xFFFF;
cycles_used = ((loop_count - 1) * 4) + 5;
- emit_insn (gen_delay_cycles_2 (gen_int_mode (loop_count, HImode)));
+ emit_insn (gen_delay_cycles_2 (gen_int_mode (loop_count, HImode),
+ avr_mem_clobber()));
cycles -= cycles_used;
}
@@ -10014,7 +10025,8 @@ avr_expand_delay_cycles (rtx operands0)
if (loop_count > 255)
loop_count = 255;
cycles_used = loop_count * 3;
- emit_insn (gen_delay_cycles_1 (gen_int_mode (loop_count, QImode)));
+ emit_insn (gen_delay_cycles_1 (gen_int_mode (loop_count, QImode),
+ avr_mem_clobber()));
cycles -= cycles_used;
}