6502/CLK
1
0
Fork 0
mirror of https://github.com/TomHarte/CLK.git synced 2024-07-04 18:29:40 +00:00
Code Issues Projects Releases Wiki Activity

Provide 64-bit me, mb and sh. Add direct getter for rotate masks.

Browse Source
This commit is contained in:
Thomas Harte 2022-04-09 21:08:01 -04:00
parent 4652a84b43
commit 7de50b5e2e
1 changed files with 33 additions and 7 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

40
InstructionSets/PowerPC/Instruction.hpp
View File

@ -1423,12 +1423,31 @@ struct Instruction {
/// Branch displacement; provided as already sign extended.
int16_t bd() const { return int16_t(opcode & 0xfffc); }
// TODO: both MB/ME and mb/me fields seem to be defined. Investigate.
/// Specifies the first 1 bit of a 32-bit mask for 32-bit rotate operations.
template <typename IntT> IntT mb() const {
if constexpr (sizeof(IntT) == 4) {
return (opcode >> 6) & 0x1f;
} else {
return (opcode >> 5) & 0x3f;
}
}
/// Specifies the first 1 bit of a 32/64-bit mask for rotate operations.
/// Specify IntT as uint32_t for the 32-bit rotate instructions, uint64_t for the 64-bit.
template <typename IntT> IntT me() const {
if constexpr (sizeof(IntT) == 4) {
return (opcode >> 1) & 0x1f;
} else {
return (opcode >> 5) & 0x3f;
}
}
/// Specifies the first 1 bit of a 32/64-bit mask for rotate operations.
uint32_t mb() const { return (opcode >> 6) & 0x1f; }
/// Specifies the first 1 bit of a 32/64-bit mask for rotate operations.
uint32_t me() const { return (opcode >> 1) & 0x1f; }
/// Provides the mask described by 32-bit rotate operations.
/// i.e. all bits from mb() to me() inclusive.
uint32_t rotate_mask() const {
const uint32_t mb_bit = 0x8000'0000 >> mb<uint32_t>();
const uint32_t me_bit = 0x8000'0000 >> mb<uint32_t>();
return mb_bit - me_bit + mb_bit;
}
/// Condition register source bit A.
uint32_t crbA() const { return (opcode >> 16) & 0x1f; }
@ -1456,8 +1475,15 @@ struct Instruction {
return ((nb - 1) & 31) + 1;
}
/// Specifies a shift amount.
uint32_t sh() const { return (opcode >> 11) & 0x1f; }
/// Specifies a shift amount. Use IntT = uint32_t to get the shift value embedded in
/// 32-bit instructions, uint64_t for 64-bit instructions.
template <typename IntT> uint32_t sh() const {
uint32_t sh = (opcode >> 11) & 0x1f;
if constexpr (sizeof(IntT) == 8) {
sh |= (opcode & 2) << 4;
}
return sh;
}
/// Specifies one of the 16 segment registers [32-bit only].
uint32_t sr() const { return (opcode >> 16) & 0xf; }