diff options
Diffstat (limited to 'subx/014indirect_addressing.cc')
-rw-r--r-- | subx/014indirect_addressing.cc | 64 |
1 files changed, 0 insertions, 64 deletions
diff --git a/subx/014indirect_addressing.cc b/subx/014indirect_addressing.cc index c6bedace..1e20cff5 100644 --- a/subx/014indirect_addressing.cc +++ b/subx/014indirect_addressing.cc @@ -382,70 +382,6 @@ case 0x8b: { // copy r32 to r/m32 break; } -//: - -:(before "End Initialize Op Names(name)") -put(name, "88", "copy r8 (lowermost byte of r32) to r8/m8-at-r32"); - -:(scenario copy_r8_to_mem_at_r32) -% Reg[EBX].i = 0x224488ab; -% Reg[EAX].i = 0x2000; -== 0x1 -# op ModR/M SIB displacement immediate - 88 18 # copy just the lowermost byte of EBX to the byte at *EAX -# ModR/M in binary: 00 (indirect mode) 011 (src EBX) 000 (dest EAX) -== 0x2000 -f0 cc bb aa # 0xf0 with more data in following bytes -+run: copy lowermost byte of EBX to r8/m8-at-r32 -+run: effective address is 0x2000 (EAX) -+run: storing 0xab -% CHECK_EQ(0xaabbccab, read_mem_u32(0x2000)); - -:(before "End Single-Byte Opcodes") -case 0x88: { // copy r8 to r/m8 - const uint8_t modrm = next(); - const uint8_t rsrc = (modrm>>3)&0x7; - trace(90, "run") << "copy lowermost byte of " << rname(rsrc) << " to r8/m8-at-r32" << end(); - // use unsigned to zero-extend 8-bit value to 32 bits - uint8_t* dest = reinterpret_cast<uint8_t*>(effective_address(modrm)); - *dest = Reg[rsrc].u; - trace(90, "run") << "storing 0x" << HEXBYTE << NUM(*dest) << end(); - break; -} - -//: - -:(before "End Initialize Op Names(name)") -put(name, "8a", "copy r8/m8-at-r32 to r8 (lowermost byte of r32)"); - -:(scenario copy_mem_at_r32_to_r8) -% Reg[EBX].i = 0xaabbcc0f; // one nibble each of lowest byte set to all 0s and all 1s, to maximize value of this test -% Reg[EAX].i = 0x2000; -== 0x1 -# op ModR/M SIB displacement immediate - 8a 18 # copy just the byte at *EAX to lowermost byte of EBX (clearing remaining bytes) -# ModR/M in binary: 00 (indirect mode) 011 (dest EBX) 000 (src EAX) -== 0x2000 # data segment -ab ff ff ff # 0xab with more data in following bytes -+run: copy r8/m8-at-r32 to lowermost byte of EBX -+run: effective address is 0x2000 (EAX) -+run: storing 0xab -# remaining bytes of EBX are *not* cleared -+run: EBX now contains 0xaabbccab - -:(before "End Single-Byte Opcodes") -case 0x8a: { // copy r/m8 to r8 - const uint8_t modrm = next(); - const uint8_t rdest = (modrm>>3)&0x7; - trace(90, "run") << "copy r8/m8-at-r32 to lowermost byte of " << rname(rdest) << end(); - // use unsigned to zero-extend 8-bit value to 32 bits - const uint8_t* src = reinterpret_cast<uint8_t*>(effective_address(modrm)); - trace(90, "run") << "storing 0x" << HEXBYTE << NUM(*src) << end(); - *reinterpret_cast<uint8_t*>(&Reg[rdest].u) = *src; // assumes host is little-endian - trace(90, "run") << rname(rdest) << " now contains 0x" << HEXWORD << Reg[rdest].u << end(); - break; -} - //:: jump :(scenario jump_mem_at_r32) |