1 files changed, 52 insertions, 0 deletions
diff --git a/yjit/src/asm/arm64/arg/condition.rs b/yjit/src/asm/arm64/arg/condition.rs
new file mode 100644
index 0000000000..f711b8b0d8
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+++ b/yjit/src/asm/arm64/arg/condition.rs
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+/// Various instructions in A64 can have condition codes attached. This enum
+/// includes all of the various kinds of conditions along with their respective
+/// encodings.
+pub struct Condition;
+
+impl Condition {
+    pub const EQ: u8 = 0b0000; // equal to
+    pub const NE: u8 = 0b0001; // not equal to
+    pub const CS: u8 = 0b0010; // carry set (alias for HS)
+    pub const CC: u8 = 0b0011; // carry clear (alias for LO)
+    pub const MI: u8 = 0b0100; // minus, negative
+    pub const PL: u8 = 0b0101; // positive or zero
+    pub const VS: u8 = 0b0110; // signed overflow
+    pub const VC: u8 = 0b0111; // no signed overflow
+    pub const HI: u8 = 0b1000; // greater than (unsigned)
+    pub const LS: u8 = 0b1001; // less than or equal to (unsigned)
+    pub const GE: u8 = 0b1010; // greater than or equal to (signed)
+    pub const LT: u8 = 0b1011; // less than (signed)
+    pub const GT: u8 = 0b1100; // greater than (signed)
+    pub const LE: u8 = 0b1101; // less than or equal to (signed)
+    pub const AL: u8 = 0b1110; // always
+
+    pub const fn inverse(condition: u8) -> u8 {
+        match condition {
+            Condition::EQ => Condition::NE,
+            Condition::NE => Condition::EQ,
+
+            Condition::CS => Condition::CC,
+            Condition::CC => Condition::CS,
+
+            Condition::MI => Condition::PL,
+            Condition::PL => Condition::MI,
+
+            Condition::VS => Condition::VC,
+            Condition::VC => Condition::VS,
+
+            Condition::HI => Condition::LS,
+            Condition::LS => Condition::HI,
+
+            Condition::LT => Condition::GE,
+            Condition::GE => Condition::LT,
+
+            Condition::GT => Condition::LE,
+            Condition::LE => Condition::GT,
+
+            Condition::AL => Condition::AL,
+
+            _ => panic!("Unknown condition")
+
+        }
+    }
+}