@@ -34,26 +34,41 @@ (define_code_attr atomic_optab
;; Memory barriers.
(define_expand "mem_thread_fence"
- [(match_operand:SI 0 "const_int_operand" "")] ;; model
+ [(match_operand:SI 0 "const_int_operand")] ;; model
""
{
- if (INTVAL (operands[0]) != MEMMODEL_RELAXED)
- {
- rtx mem = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
- MEM_VOLATILE_P (mem) = 1;
- emit_insn (gen_mem_thread_fence_1 (mem, operands[0]));
- }
+ enum memmodel model = memmodel_from_int (INTVAL (operands[0]));
+ if (!(is_mm_relaxed (model)))
+ emit_insn (gen_mem_fence (operands[0]));
DONE;
})
-;; Until the RISC-V memory model (hence its mapping from C++) is finalized,
-;; conservatively emit a full FENCE.
-(define_insn "mem_thread_fence_1"
+(define_expand "mem_fence"
+ [(set (match_dup 1)
+ (unspec:BLK [(match_dup 1) (match_operand:SI 0 "const_int_operand")]
+ UNSPEC_MEMORY_BARRIER))]
+ ""
+{
+ operands[1] = gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (Pmode));
+ MEM_VOLATILE_P (operands[1]) = 1;
+})
+
+(define_insn "*mem_fence"
[(set (match_operand:BLK 0 "" "")
- (unspec:BLK [(match_dup 0)] UNSPEC_MEMORY_BARRIER))
- (match_operand:SI 1 "const_int_operand" "")] ;; model
+ (unspec:BLK [(match_dup 0) (match_operand:SI 1 "const_int_operand")]
+ UNSPEC_MEMORY_BARRIER))]
""
- "fence\tiorw,iorw")
+{
+ enum memmodel model = memmodel_from_int (INTVAL (operands[1]));
+ if (is_mm_consume (model) || is_mm_acquire (model))
+ return "fence\tr, rw";
+ else if (is_mm_release (model))
+ return "fence\trw, w";
+ else if (is_mm_acq_rel (model))
+ return "fence.tso";
+ else
+ return "fence\trw, rw";
+})
;; Atomic memory operations.
mem_thread_fence gets the desired memory model as operand. Let's emit fences according to this value (as defined in section "Code Porting and Mapping Guidelines" of the unpriv spec). gcc/ PR 100265 * config/riscv/sync.md (mem_thread_fence): Emit fences according to given operand. * config/riscv/sync.md (mem_fence): Add INSNs for different fence flavours. * config/riscv/sync.md (mem_thread_fence_1): Remove. --- gcc/config/riscv/sync.md | 41 +++++++++++++++++++++++++++------------- 1 file changed, 28 insertions(+), 13 deletions(-)