jit stosb/stosw/stosd

gen/x86_table.js

@@ -232,10 +232,10 @@ const encodings = [
     { opcode: 0xA8, custom: 1, imm8: 1, },
     { opcode: 0xA9, custom: 1, os: 1, imm1632: 1, },
 
-    { opcode: 0xAA, block_boundary: 1, custom: 1, is_string: 1, },
+    { opcode: 0xAA, block_boundary: 0, custom: 1, is_string: 1, },
     { opcode: 0xF2AA, block_boundary: 1, custom: 1, is_string: 1, },
     { opcode: 0xF3AA, block_boundary: 1, custom: 1, is_string: 1, },
-    { opcode: 0xAB, block_boundary: 1, custom: 1, is_string: 1, os: 1, },
+    { opcode: 0xAB, block_boundary: 0, custom: 1, is_string: 1, os: 1, },
     { opcode: 0xF2AB, block_boundary: 1, custom: 1, is_string: 1, os: 1, },
     { opcode: 0xF3AB, block_boundary: 1, custom: 1, is_string: 1, os: 1, },
 

src/rust/cpu/string.rs

@@ -517,15 +517,12 @@ pub unsafe fn stosw_rep(is_asize_32: bool) {
 pub unsafe fn stosd_rep(is_asize_32: bool) {
     string_instruction(is_asize_32, 0, Instruction::Stos, Size::D, Rep::Z)
 }
-#[no_mangle]
 pub unsafe fn stosb_no_rep(is_asize_32: bool) {
     string_instruction(is_asize_32, 0, Instruction::Stos, Size::B, Rep::None)
 }
-#[no_mangle]
 pub unsafe fn stosw_no_rep(is_asize_32: bool) {
     string_instruction(is_asize_32, 0, Instruction::Stos, Size::W, Rep::None)
 }
-#[no_mangle]
 pub unsafe fn stosd_no_rep(is_asize_32: bool) {
     string_instruction(is_asize_32, 0, Instruction::Stos, Size::D, Rep::None)
 }

src/rust/jit_instructions.rs

@@ -4557,6 +4557,39 @@ fn gen_string_ins(ctx: &mut JitContext, ins: String, size: u8, prefix: u8) {
                 }
                 return;
             },
+            String::STOS => {
+                if ctx.cpu.asize_32() {
+                    codegen::gen_get_reg32(ctx, regs::EDI);
+                }
+                else {
+                    codegen::gen_get_reg16(ctx, regs::EDI);
+                }
+                jit_add_seg_offset_no_override(ctx, regs::ES);
+                let address_local = ctx.builder.set_new_local();
+                if size == 8 {
+                    codegen::gen_safe_write8(ctx, &address_local, &ctx.reg(regs::AL));
+                    ctx.builder.free_local(address_local);
+                }
+                else if size == 16 {
+                    codegen::gen_safe_write16(ctx, &address_local, &ctx.reg(regs::AX));
+                    ctx.builder.free_local(address_local);
+                }
+                else {
+                    codegen::gen_safe_write32(ctx, &address_local, &ctx.reg(regs::EAX));
+                    ctx.builder.free_local(address_local);
+                }
+
+                codegen::gen_get_reg32(ctx, regs::EDI);
+                get_direction(ctx, size);
+                ctx.builder.add_i32();
+                if ctx.cpu.asize_32() {
+                    codegen::gen_set_reg32(ctx, regs::EDI);
+                }
+                else {
+                    codegen::gen_set_reg16(ctx, regs::EDI);
+                }
+                return;
+            },
             _ => {},
         }
     }