[mono][llvm] Use the OP_MEMMOVE opcode instead of calling the managed memcpy method...

LLVM can emit optimized code when the length ends up being a constant.

diff --git a/src/mono/mono/mini/memory-access.c b/src/mono/mono/mini/memory-access.c
index 58d9c54..ceae7a3 100644 (file)
--- a/src/mono/mono/mini/memory-access.c
+++ b/src/mono/mono/mini/memory-access.c
@@ -210,7 +210,16 @@ mini_emit_memcpy_internal (MonoCompile *cfg, MonoInst *dest, MonoInst *src, Mono
                if (!size_ins)
                        EMIT_NEW_ICONST (cfg, size_ins, size);
                iargs [2] = size_ins;
-               mono_emit_method_call (cfg, mini_get_memcpy_method (), iargs, NULL);
+               if (COMPILE_LLVM (cfg)) {
+                       MonoInst *ins;
+                       MONO_INST_NEW (cfg, ins, OP_MEMMOVE);
+                       ins->sreg1 = iargs [0]->dreg;
+                       ins->sreg2 = iargs [1]->dreg;
+                       ins->sreg3 = iargs [2]->dreg;
+                       MONO_ADD_INS (cfg->cbb, ins);
+               } else {
+                       mono_emit_method_call (cfg, mini_get_memcpy_method (), iargs, NULL);
+               }
        } else {
                mini_emit_memcpy (cfg, dest->dreg, 0, src->dreg, 0, size, align);
        }