ruby-changes:68687
From: Maxime <ko1@a...>
Date: Thu, 21 Oct 2021 08:12:25 +0900 (JST)
Subject: [ruby-changes:68687] 0c52371c47 (master): Don't create a stack frame for Hash#key?
https://git.ruby-lang.org/ruby.git/commit/?id=0c52371c47 From 0c52371c47d8b65f91ed5d2a7e2c14c96d286f57 Mon Sep 17 00:00:00 2001 From: Maxime Chevalier-Boisvert <maxime.chevalierboisvert@s...> Date: Tue, 27 Oct 2020 15:58:26 -0400 Subject: Don't create a stack frame for Hash#key? --- ujit_compile.c | 144 ++++++++++++++++++++++++++++++++------------------------- 1 file changed, 80 insertions(+), 64 deletions(-) diff --git a/ujit_compile.c b/ujit_compile.c index dc0509d703..93c9303763 100644 --- a/ujit_compile.c +++ b/ujit_compile.c @@ -483,6 +483,21 @@ gen_opt_minus(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx) https://github.com/ruby/ruby/blob/trunk/ujit_compile.c#L483 return true; } +MJIT_FUNC_EXPORTED VALUE rb_hash_has_key(VALUE hash, VALUE key); + +bool +cfunc_needs_frame(const rb_method_cfunc_t *cfunc) +{ + void* fptr = (void*)cfunc->func; + + // Leaf C functions do not need a stack frame + // or a stack overflow check + return !( + // Hash#key? + fptr == (void*)rb_hash_has_key + ); +} + bool gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx) { @@ -590,64 +605,61 @@ gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx) https://github.com/ruby/ruby/blob/trunk/ujit_compile.c#L605 test(cb, flags_opnd, imm_opnd(IMEMO_FL_USER5)); jnz_ptr(cb, side_exit); - // IDEA: stack frame setup may not be needed for some C functions - // We could profile the most called C functions and identify which are safe - // This may help us eliminate stack overflow checks as well - - - - - // Stack overflow check - // #define CHECK_VM_STACK_OVERFLOW0(cfp, sp, margin) - // REG_CFP <= REG_SP + 4 * sizeof(VALUE) + sizeof(rb_control_frame_t) - lea(cb, REG0, ctx_sp_opnd(ctx, sizeof(VALUE) * 4 + sizeof(rb_control_frame_t))); - cmp(cb, REG_CFP, REG0); - jle_ptr(cb, side_exit); - - // Increment the stack pointer by 3 (in the callee) - // sp += 3 - lea(cb, REG0, ctx_sp_opnd(ctx, sizeof(VALUE) * 3)); - - // Write method entry at sp[-3] - // sp[-3] = me; - mov(cb, mem_opnd(64, REG0, 8 * -3), REG1); - - // Write block handler at sp[-2] - // sp[-2] = block_handler; - mov(cb, mem_opnd(64, REG0, 8 * -2), imm_opnd(VM_BLOCK_HANDLER_NONE)); - - // Write env flags at sp[-1] - // sp[-1] = frame_type; - uint64_t frame_type = VM_FRAME_MAGIC_CFUNC | VM_FRAME_FLAG_CFRAME | VM_ENV_FLAG_LOCAL; - mov(cb, mem_opnd(64, REG0, 8 * -1), imm_opnd(frame_type)); - - // Allocate a new CFP (ec->cfp--) - sub( - cb, - member_opnd(REG_EC, rb_execution_context_t, cfp), - imm_opnd(sizeof(rb_control_frame_t)) - ); - - // Setup the new frame - // *cfp = (const struct rb_control_frame_struct) { - // .pc = 0, - // .sp = sp, - // .iseq = 0, - // .self = recv, - // .ep = sp - 1, - // .block_code = 0, - // .__bp__ = sp, - // }; - mov(cb, REG1, member_opnd(REG_EC, rb_execution_context_t, cfp)); - mov(cb, member_opnd(REG1, rb_control_frame_t, pc), imm_opnd(0)); - mov(cb, member_opnd(REG1, rb_control_frame_t, sp), REG0); - mov(cb, member_opnd(REG1, rb_control_frame_t, iseq), imm_opnd(0)); - mov(cb, member_opnd(REG1, rb_control_frame_t, block_code), imm_opnd(0)); - mov(cb, member_opnd(REG1, rb_control_frame_t, __bp__), REG0); - sub(cb, REG0, imm_opnd(sizeof(VALUE))); - mov(cb, member_opnd(REG1, rb_control_frame_t, ep), REG0); - mov(cb, REG0, recv); - mov(cb, member_opnd(REG1, rb_control_frame_t, self), REG0); + // If this function needs a Ruby stack frame + if (cfunc_needs_frame(cfunc)) + { + // Stack overflow check + // #define CHECK_VM_STACK_OVERFLOW0(cfp, sp, margin) + // REG_CFP <= REG_SP + 4 * sizeof(VALUE) + sizeof(rb_control_frame_t) + lea(cb, REG0, ctx_sp_opnd(ctx, sizeof(VALUE) * 4 + sizeof(rb_control_frame_t))); + cmp(cb, REG_CFP, REG0); + jle_ptr(cb, side_exit); + + // Increment the stack pointer by 3 (in the callee) + // sp += 3 + lea(cb, REG0, ctx_sp_opnd(ctx, sizeof(VALUE) * 3)); + + // Write method entry at sp[-3] + // sp[-3] = me; + mov(cb, mem_opnd(64, REG0, 8 * -3), REG1); + + // Write block handler at sp[-2] + // sp[-2] = block_handler; + mov(cb, mem_opnd(64, REG0, 8 * -2), imm_opnd(VM_BLOCK_HANDLER_NONE)); + + // Write env flags at sp[-1] + // sp[-1] = frame_type; + uint64_t frame_type = VM_FRAME_MAGIC_CFUNC | VM_FRAME_FLAG_CFRAME | VM_ENV_FLAG_LOCAL; + mov(cb, mem_opnd(64, REG0, 8 * -1), imm_opnd(frame_type)); + + // Allocate a new CFP (ec->cfp--) + sub( + cb, + member_opnd(REG_EC, rb_execution_context_t, cfp), + imm_opnd(sizeof(rb_control_frame_t)) + ); + + // Setup the new frame + // *cfp = (const struct rb_control_frame_struct) { + // .pc = 0, + // .sp = sp, + // .iseq = 0, + // .self = recv, + // .ep = sp - 1, + // .block_code = 0, + // .__bp__ = sp, + // }; + mov(cb, REG1, member_opnd(REG_EC, rb_execution_context_t, cfp)); + mov(cb, member_opnd(REG1, rb_control_frame_t, pc), imm_opnd(0)); + mov(cb, member_opnd(REG1, rb_control_frame_t, sp), REG0); + mov(cb, member_opnd(REG1, rb_control_frame_t, iseq), imm_opnd(0)); + mov(cb, member_opnd(REG1, rb_control_frame_t, block_code), imm_opnd(0)); + mov(cb, member_opnd(REG1, rb_control_frame_t, __bp__), REG0); + sub(cb, REG0, imm_opnd(sizeof(VALUE))); + mov(cb, member_opnd(REG1, rb_control_frame_t, ep), REG0); + mov(cb, REG0, recv); + mov(cb, member_opnd(REG1, rb_control_frame_t, self), REG0); + } // Save the MicroJIT registers push(cb, REG_CFP); @@ -693,12 +705,16 @@ gen_opt_send_without_block(codeblock_t* cb, codeblock_t* ocb, ctx_t* ctx) https://github.com/ruby/ruby/blob/trunk/ujit_compile.c#L705 x86opnd_t stack_ret = ctx_stack_push(ctx, 1); mov(cb, stack_ret, RAX); - // Pop the stack frame (ec->cfp++) - add( - cb, - member_opnd(REG_EC, rb_execution_context_t, cfp), - imm_opnd(sizeof(rb_control_frame_t)) - ); + // If this function needs a Ruby stack frame + if (cfunc_needs_frame(cfunc)) + { + // Pop the stack frame (ec->cfp++) + add( + cb, + member_opnd(REG_EC, rb_execution_context_t, cfp), + imm_opnd(sizeof(rb_control_frame_t)) + ); + } return true; } -- cgit v1.2.1 -- ML: ruby-changes@q... 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