MicroJIT: coalesce heap pointer check on self

This commit is contained in:
Alan Wu 2020-11-20 11:35:17 -05:00
parent 4d964e2582
commit fa04478e9e

View File

@ -55,6 +55,9 @@ typedef struct ctx_struct
// The start of the generated code
uint8_t *code_ptr;
// Whether we know self is a heap object
bool self_is_heap_object;
} ctx_t;
// MicroJIT code generation function signature
@ -407,9 +410,7 @@ ujit_compile_insn(const rb_iseq_t *iseq, unsigned int insn_idx, unsigned int *ne
int first_opcode = opcode_at_pc(iseq, &encoded[insn_idx]);
// Create codegen context
ctx_t ctx;
ctx.pc = NULL;
ctx.stack_diff = 0;
ctx_t ctx = { 0 };
ctx.iseq = iseq;
ctx.code_ptr = code_ptr;
ctx.start_idx = insn_idx;
@ -624,6 +625,22 @@ gen_setlocal_wc0(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
return true;
}
// Check that `self` is a pointer to an object on the GC heap
static void
ensure_self_is_heap_object(codeblock_t *cb, x86opnd_t storage_for_self, uint8_t *side_exit, ctx_t *ctx)
{
// `self` is constant throughout the entire region, so we only need to do this check once.
if (!ctx->self_is_heap_object) {
test(cb, storage_for_self, imm_opnd(RUBY_IMMEDIATE_MASK));
jnz_ptr(cb, side_exit);
cmp(cb, storage_for_self, imm_opnd(Qfalse));
je_ptr(cb, side_exit);
cmp(cb, storage_for_self, imm_opnd(Qnil));
je_ptr(cb, side_exit);
ctx->self_is_heap_object = true;
}
}
static bool
gen_getinstancevariable(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
{
@ -652,13 +669,7 @@ gen_getinstancevariable(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
// Load self from CFP
mov(cb, REG0, member_opnd(REG_CFP, rb_control_frame_t, self));
// Check that the receiver is a heap object
test(cb, REG0, imm_opnd(RUBY_IMMEDIATE_MASK));
jnz_ptr(cb, side_exit);
cmp(cb, REG0, imm_opnd(Qfalse));
je_ptr(cb, side_exit);
cmp(cb, REG0, imm_opnd(Qnil));
je_ptr(cb, side_exit);
ensure_self_is_heap_object(cb, REG0, side_exit, ctx);
// Bail if receiver class is different from compiled time call cache class
x86opnd_t klass_opnd = mem_opnd(64, REG0, offsetof(struct RBasic, klass));
@ -720,13 +731,7 @@ gen_setinstancevariable(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx)
// Load self from CFP
mov(cb, REG0, member_opnd(REG_CFP, rb_control_frame_t, self));
// Check that the receiver is a heap object
test(cb, REG0, imm_opnd(RUBY_IMMEDIATE_MASK));
jnz_ptr(cb, side_exit);
cmp(cb, REG0, imm_opnd(Qfalse));
je_ptr(cb, side_exit);
cmp(cb, REG0, imm_opnd(Qnil));
je_ptr(cb, side_exit);
ensure_self_is_heap_object(cb, REG0, side_exit, ctx);
// Bail if receiver class is different from compiled time call cache class
x86opnd_t klass_opnd = mem_opnd(64, REG0, offsetof(struct RBasic, klass));