Spill failure PR52148 occurs for movmem insn that allocates 2 of AVR's 3
pointer registers. Register allocator is at it's limits and the patch tries to
cure the situation by replacing
(match_operand:HI 0 "register_operand" "x")
with explicit
(reg:HI REG_X)
and similar for Z Register classes "x" and "z" contain only one HI register.
This PR and PR50925 show that register allocator has some problems.
Even though this patch is not a fix of the root cause, it allows the PR's test
case to compile.
Anyways, the patch simplifies the backend and replaces an insn with 11(!)
operands with an insn with only 2 operands so that the patch is improvement of
the backend.
The hard registers are already known at expand time so there is no need for
match_operands.
Passes without regression.
Ok for trunk?
Johann
PR target/52148
* config/avr/avr.md (movmem_<mode>): Replace match_operand that
match only one single hard register with respective hard reg rtx.
(movmemx_<mode>): Ditto.
* config/avr/avr.c (avr_emit_movmemhi): Adapt expanding to new
insn anatomy of movmem[x]_<mode>.
(avr_out_movmem): Same for printing assembler and operand usage.
Index: config/avr/avr.md
===================================================================
--- config/avr/avr.md (revision 184269)
+++ config/avr/avr.md (working copy)
@@ -461,6 +461,9 @@ (define_insn "xload_8"
(set_attr "isa" "lpmx,lpm")
(set_attr "cc" "none")])
+;; R21:Z : 24-bit source address
+;; R22 : 1-4 byte output
+
;; "xload_qi_libgcc"
;; "xload_hi_libgcc"
;; "xload_psi_libgcc"
@@ -841,24 +844,23 @@ (define_expand "movmemhi"
(define_mode_attr MOVMEM_r_d [(QI "r")
(HI "wd")])
-;; $0, $4 : & dest (REG_X)
-;; $1, $5 : & src (REG_Z)
-;; $2 : Address Space
-;; $3, $7 : Loop register
-;; $6 : Scratch register
+;; $0 : Address Space
+;; $1, $2 : Loop register
+;; R30 : source address
+;; R26 : destination address
;; "movmem_qi"
;; "movmem_hi"
(define_insn "movmem_<mode>"
- [(set (mem:BLK (match_operand:HI 0 "register_operand" "x"))
- (mem:BLK (match_operand:HI 1 "register_operand" "z")))
- (unspec [(match_operand:QI 2 "const_int_operand" "n")]
+ [(set (mem:BLK (reg:HI REG_X))
+ (mem:BLK (reg:HI REG_Z)))
+ (unspec [(match_operand:QI 0 "const_int_operand" "n")]
UNSPEC_MOVMEM)
- (use (match_operand:QIHI 3 "register_operand" "<MOVMEM_r_d>"))
- (clobber (match_operand:HI 4 "register_operand" "=0"))
- (clobber (match_operand:HI 5 "register_operand" "=1"))
- (clobber (match_operand:QI 6 "register_operand" "=&r"))
- (clobber (match_operand:QIHI 7 "register_operand" "=3"))]
+ (use (match_operand:QIHI 1 "register_operand" "<MOVMEM_r_d>"))
+ (clobber (reg:HI REG_X))
+ (clobber (reg:HI REG_Z))
+ (clobber (reg:QI LPM_REGNO))
+ (clobber (match_operand:QIHI 2 "register_operand" "=1"))]
""
{
return avr_out_movmem (insn, operands, NULL);
@@ -866,26 +868,28 @@ (define_insn "movmem_<mode>"
[(set_attr "adjust_len" "movmem")
(set_attr "cc" "clobber")])
-;; Ditto and
-;; $3, $7 : Loop register = R24
-;; $8, $9 : hh8 (& src) = R23
-;; $10 : RAMPZ_ADDR
+
+;; $0 : Address Space
+;; $1 : RAMPZ RAM address
+;; R24 : #bytes and loop register
+;; R23:Z : 24-bit source address
+;; R26 : 16-bit destination address
;; "movmemx_qi"
;; "movmemx_hi"
(define_insn "movmemx_<mode>"
- [(set (mem:BLK (match_operand:HI 0 "register_operand" "x"))
- (mem:BLK (lo_sum:PSI (match_operand:QI 8 "register_operand" "r")
- (match_operand:HI 1 "register_operand" "z"))))
- (unspec [(match_operand:QI 2 "const_int_operand" "n")]
+ [(set (mem:BLK (reg:HI REG_X))
+ (mem:BLK (lo_sum:PSI (reg:QI 23)
+ (reg:HI REG_Z))))
+ (unspec [(match_operand:QI 0 "const_int_operand" "n")]
UNSPEC_MOVMEM)
- (use (match_operand:QIHI 3 "register_operand" "w"))
- (clobber (match_operand:HI 4 "register_operand" "=0"))
- (clobber (match_operand:HI 5 "register_operand" "=1"))
- (clobber (match_operand:QI 6 "register_operand" "=&r"))
- (clobber (match_operand:HI 7 "register_operand" "=3"))
- (clobber (match_operand:QI 9 "register_operand" "=8"))
- (clobber (mem:QI (match_operand:QI 10 "io_address_operand" "n")))]
+ (use (reg:QIHI 24))
+ (clobber (reg:HI REG_X))
+ (clobber (reg:HI REG_Z))
+ (clobber (reg:QI LPM_REGNO))
+ (clobber (reg:HI 24))
+ (clobber (reg:QI 23))
+ (clobber (mem:QI (match_operand:QI 1 "io_address_operand" "n")))]
""
"%~call __movmemx_<mode>"
[(set_attr "type" "xcall")
Index: config/avr/avr.c
===================================================================
--- config/avr/avr.c (revision 184269)
+++ config/avr/avr.c (working copy)
@@ -9898,7 +9898,7 @@ avr_emit_movmemhi (rtx *xop)
HOST_WIDE_INT count;
enum machine_mode loop_mode;
addr_space_t as = MEM_ADDR_SPACE (xop[1]);
- rtx loop_reg, addr0, addr1, a_src, a_dest, insn, xas, reg_x;
+ rtx loop_reg, addr1, a_src, a_dest, insn, xas;
rtx a_hi8 = NULL_RTX;
if (avr_mem_flash_p (xop[0]))
@@ -9927,7 +9927,7 @@ avr_emit_movmemhi (rtx *xop)
}
else
{
- int segment = avr_addrspace[as].segment % avr_current_arch->n_segments;
+ int segment = avr_addrspace[as].segment;
if (segment
&& avr_current_arch->n_segments > 1)
@@ -9954,11 +9954,7 @@ avr_emit_movmemhi (rtx *xop)
X = destination address */
emit_move_insn (lpm_addr_reg_rtx, addr1);
- addr1 = lpm_addr_reg_rtx;
-
- reg_x = gen_rtx_REG (HImode, REG_X);
- emit_move_insn (reg_x, a_dest);
- addr0 = reg_x;
+ emit_move_insn (gen_rtx_REG (HImode, REG_X), a_dest);
/* FIXME: Register allocator does a bad job and might spill address
register(s) inside the loop leading to additional move instruction
@@ -9973,23 +9969,19 @@ avr_emit_movmemhi (rtx *xop)
/* Load instruction ([E]LPM or LD) is known at compile time:
Do the copy-loop inline. */
- rtx (*fun) (rtx, rtx, rtx, rtx, rtx, rtx, rtx, rtx)
+ rtx (*fun) (rtx, rtx, rtx)
= QImode == loop_mode ? gen_movmem_qi : gen_movmem_hi;
- insn = fun (addr0, addr1, xas, loop_reg,
- addr0, addr1, tmp_reg_rtx, loop_reg);
+ insn = fun (xas, loop_reg, loop_reg);
}
else
{
- rtx loop_reg16 = gen_rtx_REG (HImode, 24);
- rtx r23 = gen_rtx_REG (QImode, 23);
- rtx (*fun) (rtx, rtx, rtx, rtx, rtx, rtx, rtx, rtx, rtx, rtx, rtx)
+ rtx (*fun) (rtx, rtx)
= QImode == loop_mode ? gen_movmemx_qi : gen_movmemx_hi;
- emit_move_insn (r23, a_hi8);
+ emit_move_insn (gen_rtx_REG (QImode, 23), a_hi8);
- insn = fun (addr0, addr1, xas, loop_reg, addr0, addr1,
- lpm_reg_rtx, loop_reg16, r23, r23, GEN_INT (avr_addr.rampz));
+ insn = fun (xas, GEN_INT (avr_addr.rampz));
}
set_mem_addr_space (SET_SRC (XVECEXP (insn, 0, 0)), as);
@@ -10000,32 +9992,27 @@ avr_emit_movmemhi (rtx *xop)
/* Print assembler for movmem_qi, movmem_hi insns...
- $0, $4 : & dest
- $1, $5 : & src
- $2 : Address Space
- $3, $7 : Loop register
- $6 : Scratch register
-
- ...and movmem_qi_elpm, movmem_hi_elpm insns.
-
- $8, $9 : hh8 (& src)
- $10 : RAMPZ_ADDR
+ $0 : Address Space
+ $1, $2 : Loop register
+ Z : Source address
+ X : Destination address
*/
const char*
-avr_out_movmem (rtx insn ATTRIBUTE_UNUSED, rtx *xop, int *plen)
+avr_out_movmem (rtx insn ATTRIBUTE_UNUSED, rtx *op, int *plen)
{
- addr_space_t as = (addr_space_t) INTVAL (xop[2]);
- enum machine_mode loop_mode = GET_MODE (xop[3]);
-
- bool sbiw_p = test_hard_reg_class (ADDW_REGS, xop[3]);
-
- gcc_assert (REG_X == REGNO (xop[0])
- && REG_Z == REGNO (xop[1]));
+ addr_space_t as = (addr_space_t) INTVAL (op[0]);
+ enum machine_mode loop_mode = GET_MODE (op[1]);
+ bool sbiw_p = test_hard_reg_class (ADDW_REGS, op[1]);
+ rtx xop[3];
if (plen)
*plen = 0;
+ xop[0] = op[0];
+ xop[1] = op[1];
+ xop[2] = tmp_reg_rtx;
+
/* Loop label */
avr_asm_len ("0:", xop, plen, 0);
@@ -10039,16 +10026,16 @@ avr_out_movmem (rtx insn ATTRIBUTE_UNUSE
case ADDR_SPACE_GENERIC:
- avr_asm_len ("ld %6,%a1+", xop, plen, 1);
+ avr_asm_len ("ld %2,Z+", xop, plen, 1);
break;
case ADDR_SPACE_FLASH:
if (AVR_HAVE_LPMX)
- avr_asm_len ("lpm %6,%a1+", xop, plen, 1);
+ avr_asm_len ("lpm %2,%Z+", xop, plen, 1);
else
avr_asm_len ("lpm" CR_TAB
- "adiw %1,1", xop, plen, 2);
+ "adiw r30,1", xop, plen, 2);
break;
case ADDR_SPACE_FLASH1:
@@ -10058,31 +10045,31 @@ avr_out_movmem (rtx insn ATTRIBUTE_UNUSE
case ADDR_SPACE_FLASH5:
if (AVR_HAVE_ELPMX)
- avr_asm_len ("elpm %6,%a1+", xop, plen, 1);
+ avr_asm_len ("elpm %2,Z+", xop, plen, 1);
else
avr_asm_len ("elpm" CR_TAB
- "adiw %1,1", xop, plen, 2);
+ "adiw r30,1", xop, plen, 2);
break;
}
/* Store with post-increment */
- avr_asm_len ("st %a0+,%6", xop, plen, 1);
+ avr_asm_len ("st X+,%2", xop, plen, 1);
/* Decrement loop-counter and set Z-flag */
if (QImode == loop_mode)
{
- avr_asm_len ("dec %3", xop, plen, 1);
+ avr_asm_len ("dec %1", xop, plen, 1);
}
else if (sbiw_p)
{
- avr_asm_len ("sbiw %3,1", xop, plen, 1);
+ avr_asm_len ("sbiw %1,1", xop, plen, 1);
}
else
{
- avr_asm_len ("subi %A3,1" CR_TAB
- "sbci %B3,0", xop, plen, 2);
+ avr_asm_len ("subi %A1,1" CR_TAB
+ "sbci %B1,0", xop, plen, 2);
}
/* Loop until zero */
