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x64: Implement rotl and rotr for small integers

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This commit is contained in:
bjorn3
2020-08-23 10:49:44 +02:00
committed by Benjamin Bouvier
parent 4251a950ba
commit 067255ef45
4 changed files with 105 additions and 78 deletions
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39
cranelift/codegen/src/isa/x64/inst/emit.rs
View File

@@ -1133,7 +1133,7 @@ pub(crate) fn emit(
}
Inst::Shift_R {
is_64,
size,
kind,
num_bits,
dst,
@@ -1147,25 +1147,39 @@ pub(crate) fn emit(
ShiftKind::ShiftRightArithmetic => 7,
};
let rex = if *is_64 {
RexFlags::set_w()
} else {
RexFlags::clear_w()
};
match num_bits {
None => {
let (opcode, prefix, rex_flags) = match size {
1 => (0xD2, LegacyPrefixes::None, RexFlags::clear_w()),
2 => (0xD3, LegacyPrefixes::_66, RexFlags::clear_w()),
4 => (0xD3, LegacyPrefixes::None, RexFlags::clear_w()),
8 => (0xD3, LegacyPrefixes::None, RexFlags::set_w()),
_ => unreachable!("{}", size),
};
// SHL/SHR/SAR %cl, reg8 is (REX.W==0) D2 /subopcode
// SHL/SHR/SAR %cl, reg16 is 66 (REX.W==0) D3 /subopcode
// SHL/SHR/SAR %cl, reg32 is (REX.W==0) D3 /subopcode
// SHL/SHR/SAR %cl, reg64 is (REX.W==1) D3 /subopcode
emit_std_enc_enc(sink, LegacyPrefixes::None, 0xD3, 1, subopcode, enc_dst, rex);
emit_std_enc_enc(sink, prefix, opcode, 1, subopcode, enc_dst, rex_flags);
}
Some(num_bits) => {
let (opcode, prefix, rex_flags) = match size {
1 => (0xC0, LegacyPrefixes::None, RexFlags::clear_w()),
2 => (0xC1, LegacyPrefixes::_66, RexFlags::clear_w()),
4 => (0xC1, LegacyPrefixes::None, RexFlags::clear_w()),
8 => (0xC1, LegacyPrefixes::None, RexFlags::set_w()),
_ => unreachable!("{}", size),
};
// SHL/SHR/SAR $ib, reg8 is (REX.W==0) C0 /subopcode
// SHL/SHR/SAR $ib, reg16 is 66 (REX.W==0) C1 /subopcode
// SHL/SHR/SAR $ib, reg32 is (REX.W==0) C1 /subopcode ib
// SHL/SHR/SAR $ib, reg64 is (REX.W==1) C1 /subopcode ib
// When the shift amount is 1, there's an even shorter encoding, but we don't
// bother with that nicety here.
emit_std_enc_enc(sink, LegacyPrefixes::None, 0xC1, 1, subopcode, enc_dst, rex);
emit_std_enc_enc(sink, prefix, opcode, 1, subopcode, enc_dst, rex_flags);
sink.put1(*num_bits);
}
}
@@ -2054,12 +2068,7 @@ pub(crate) fn emit(
inst.emit(sink, flags, state);
// tmp_gpr1 := src >> 1
let inst = Inst::shift_r(
/*is_64*/ true,
ShiftKind::ShiftRightLogical,
Some(1),
*tmp_gpr1,
);
let inst = Inst::shift_r(8, ShiftKind::ShiftRightLogical, Some(1), *tmp_gpr1);
inst.emit(sink, flags, state);
let inst = Inst::gen_move(*tmp_gpr2, src.to_reg(), types::I64);

70
cranelift/codegen/src/isa/x64/inst/emit_tests.rs
View File

@@ -2365,130 +2365,150 @@ fn test_x64_emit() {
// ========================================================
// Shift_R
insns.push((
Inst::shift_r(false, ShiftKind::ShiftLeft, None, w_rdi),
Inst::shift_r(4, ShiftKind::ShiftLeft, None, w_rdi),
"D3E7",
"shll %cl, %edi",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftLeft, None, w_r12),
Inst::shift_r(4, ShiftKind::ShiftLeft, None, w_r12),
"41D3E4",
"shll %cl, %r12d",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftLeft, Some(2), w_r8),
Inst::shift_r(4, ShiftKind::ShiftLeft, Some(2), w_r8),
"41C1E002",
"shll $2, %r8d",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftLeft, Some(31), w_r13),
Inst::shift_r(4, ShiftKind::ShiftLeft, Some(31), w_r13),
"41C1E51F",
"shll $31, %r13d",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftLeft, None, w_r13),
Inst::shift_r(8, ShiftKind::ShiftLeft, None, w_r13),
"49D3E5",
"shlq %cl, %r13",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftLeft, None, w_rdi),
Inst::shift_r(8, ShiftKind::ShiftLeft, None, w_rdi),
"48D3E7",
"shlq %cl, %rdi",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftLeft, Some(2), w_r8),
Inst::shift_r(8, ShiftKind::ShiftLeft, Some(2), w_r8),
"49C1E002",
"shlq $2, %r8",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftLeft, Some(3), w_rbx),
Inst::shift_r(8, ShiftKind::ShiftLeft, Some(3), w_rbx),
"48C1E303",
"shlq $3, %rbx",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftLeft, Some(63), w_r13),
Inst::shift_r(8, ShiftKind::ShiftLeft, Some(63), w_r13),
"49C1E53F",
"shlq $63, %r13",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftRightLogical, None, w_rdi),
Inst::shift_r(4, ShiftKind::ShiftRightLogical, None, w_rdi),
"D3EF",
"shrl %cl, %edi",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftRightLogical, Some(2), w_r8),
Inst::shift_r(4, ShiftKind::ShiftRightLogical, Some(2), w_r8),
"41C1E802",
"shrl $2, %r8d",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftRightLogical, Some(31), w_r13),
Inst::shift_r(4, ShiftKind::ShiftRightLogical, Some(31), w_r13),
"41C1ED1F",
"shrl $31, %r13d",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftRightLogical, None, w_rdi),
Inst::shift_r(8, ShiftKind::ShiftRightLogical, None, w_rdi),
"48D3EF",
"shrq %cl, %rdi",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftRightLogical, Some(2), w_r8),
Inst::shift_r(8, ShiftKind::ShiftRightLogical, Some(2), w_r8),
"49C1E802",
"shrq $2, %r8",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftRightLogical, Some(63), w_r13),
Inst::shift_r(8, ShiftKind::ShiftRightLogical, Some(63), w_r13),
"49C1ED3F",
"shrq $63, %r13",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftRightArithmetic, None, w_rdi),
Inst::shift_r(4, ShiftKind::ShiftRightArithmetic, None, w_rdi),
"D3FF",
"sarl %cl, %edi",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftRightArithmetic, Some(2), w_r8),
Inst::shift_r(4, ShiftKind::ShiftRightArithmetic, Some(2), w_r8),
"41C1F802",
"sarl $2, %r8d",
));
insns.push((
Inst::shift_r(false, ShiftKind::ShiftRightArithmetic, Some(31), w_r13),
Inst::shift_r(4, ShiftKind::ShiftRightArithmetic, Some(31), w_r13),
"41C1FD1F",
"sarl $31, %r13d",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftRightArithmetic, None, w_rdi),
Inst::shift_r(8, ShiftKind::ShiftRightArithmetic, None, w_rdi),
"48D3FF",
"sarq %cl, %rdi",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftRightArithmetic, Some(2), w_r8),
Inst::shift_r(8, ShiftKind::ShiftRightArithmetic, Some(2), w_r8),
"49C1F802",
"sarq $2, %r8",
));
insns.push((
Inst::shift_r(true, ShiftKind::ShiftRightArithmetic, Some(63), w_r13),
Inst::shift_r(8, ShiftKind::ShiftRightArithmetic, Some(63), w_r13),
"49C1FD3F",
"sarq $63, %r13",
));
insns.push((
Inst::shift_r(true, ShiftKind::RotateLeft, None, w_r8),
Inst::shift_r(8, ShiftKind::RotateLeft, None, w_r8),
"49D3C0",
"rolq %cl, %r8",
));
insns.push((
Inst::shift_r(false, ShiftKind::RotateLeft, Some(3), w_r9),
Inst::shift_r(4, ShiftKind::RotateLeft, Some(3), w_r9),
"41C1C103",
"roll $3, %r9d",
));
insns.push((
Inst::shift_r(false, ShiftKind::RotateRight, None, w_rsi),
Inst::shift_r(4, ShiftKind::RotateRight, None, w_rsi),
"D3CE",
"rorl %cl, %esi",
));
insns.push((
Inst::shift_r(true, ShiftKind::RotateRight, Some(5), w_r15),
Inst::shift_r(8, ShiftKind::RotateRight, Some(5), w_r15),
"49C1CF05",
"rorq $5, %r15",
));
insns.push((
Inst::shift_r(1, ShiftKind::RotateRight, None, w_rsi),
"D2CE",
"rorb %cl, %sil",
));
insns.push((
Inst::shift_r(1, ShiftKind::RotateRight, Some(5), w_r15),
"41C0CF05",
"rorb $5, %r15b",
));
insns.push((
Inst::shift_r(2, ShiftKind::RotateRight, None, w_rsi),
"66D3CE",
"rorw %cl, %si",
));
insns.push((
Inst::shift_r(2, ShiftKind::RotateRight, Some(5), w_r15),
"6641C1CF05",
"rorw $5, %r15w",
));
// ========================================================
// CmpRMIR

21
cranelift/codegen/src/isa/x64/inst/mod.rs
View File

@@ -166,9 +166,9 @@ pub enum Inst {
srcloc: Option<SourceLoc>,
},
/// Arithmetic shifts: (shl shr sar) (l q) imm reg.
/// Arithmetic shifts: (shl shr sar) (b w l q) imm reg.
Shift_R {
is_64: bool,
size: u8, // 1, 2, 4 or 8
kind: ShiftKind,
/// shift count: Some(0 .. #bits-in-type - 1), or None to mean "%cl".
num_bits: Option<u8>,
@@ -892,19 +892,20 @@ impl Inst {
}
pub(crate) fn shift_r(
is_64: bool,
size: u8,
kind: ShiftKind,
num_bits: Option<u8>,
dst: Writable<Reg>,
) -> Inst {
debug_assert!(size == 8 || size == 4 || size == 2 || size == 1);
debug_assert!(if let Some(num_bits) = num_bits {
num_bits < if is_64 { 64 } else { 32 }
num_bits < size * 8
} else {
true
});
debug_assert!(dst.to_reg().get_class() == RegClass::I64);
Inst::Shift_R {
is_64,
size,
kind,
num_bits,
dst,
@@ -1511,22 +1512,22 @@ impl ShowWithRRU for Inst {
),
Inst::Shift_R {
is_64,
size,
kind,
num_bits,
dst,
} => match num_bits {
None => format!(
"{} %cl, {}",
ljustify2(kind.to_string(), suffixLQ(*is_64)),
show_ireg_sized(dst.to_reg(), mb_rru, sizeLQ(*is_64))
ljustify2(kind.to_string(), suffixBWLQ(*size)),
show_ireg_sized(dst.to_reg(), mb_rru, *size)
),
Some(num_bits) => format!(
"{} ${}, {}",
ljustify2(kind.to_string(), suffixLQ(*is_64)),
ljustify2(kind.to_string(), suffixBWLQ(*size)),
num_bits,
show_ireg_sized(dst.to_reg(), mb_rru, sizeLQ(*is_64))
show_ireg_sized(dst.to_reg(), mb_rru, *size)
),
},