Fixing serious bug in JMP calculations

Author: raphaelcohn

workspace/assembler/Cargo.toml

@@ -15,7 +15,7 @@ exclude = ["*"]
 include = ["README.md", "LICENSE", "COPYRIGHT", "src/**/*.rs", "Cargo.toml", "rustfmt.toml", "clippy.toml"]
 readme = "README.md"
 publish = true
-version = "0.9.5"
+version = "0.9.6"
 
 [dependencies]
 libc = "^0.2"

workspace/assembler/src/ByteEmitter.rs

@@ -129,7 +129,7 @@ impl ByteEmitter
 
 		let displacement = (target_instruction_pointer as isize) - end_of_jmp_instruction;
 
-		if unlikely!(displacement >= -127 && displacement < 128)
+		if unlikely!(displacement < -128 && displacement > 127)
 		{
 			return Err(())
 		}

workspace/assembler/src/ShortJmpResult.rs

@@ -4,7 +4,7 @@
 
 /// Represents the result of attempting a mnemonic with a short jump.
 ///
-/// Will be an error if a label could be resolved and the jump exceed -127 >= < 128 bytes.
+/// Will be an error if a label could be resolved and the jump exceeded the (inclusive range) -128 to +127 bytes.
 ///
 /// In this case, the instruction stream will be reset to where it was before the prefixes, opcodes and displacements where emitted for the `Jcc` instruction.
 pub type ShortJmpResult = Result<(), ()>;

workspace/assembler/src/mnemonic_parameter_types/memory/MemoryOperand.rs

@@ -593,7 +593,7 @@ impl MemoryOperand
 		// This logic determines what the value of the mod bits will be.
 		// It also controls how many immediate bytes we emit later.
 		let displacement = self.get_displacement();
-		let mod_ = if displacement < -128 || displacement >= 128
+		let mod_ = if displacement < -128 || displacement > 127
 		{
 			Self::Mod_0b10
 		}