Add `core:text/regex`

1 files changed, 84 insertions, 0 deletions

diff --git a/core/text/regex/compiler/debugging.odin b/core/text/regex/compiler/debugging.odin
new file mode 100644
index 000000000..1ef3e6d78
--- /dev/null
+++ b/core/text/regex/compiler/debugging.odin
@@ -0,0 +1,84 @@
+package regex_compiler
+
+import "core:io"
+import "core:text/regex/common"
+import "core:text/regex/virtual_machine"
+
+get_jump_targets :: proc(code: []Opcode) -> (jump_targets: map[int]int) {
+	iter := virtual_machine.Opcode_Iterator{ code, 0 }
+	for opcode, pc in virtual_machine.iterate_opcodes(&iter) {
+		#partial switch opcode {
+		case .Jump:
+			jmp   := cast(int)(cast(^u16)&code[pc+1])^
+			jump_targets[jmp] = pc
+		case .Split:
+			jmp_x := cast(int)(cast(^u16)&code[pc+1])^
+			jmp_y := cast(int)(cast(^u16)&code[pc+3])^
+			jump_targets[jmp_x] = pc
+			jump_targets[jmp_y] = pc
+		}
+	}
+	return
+}
+
+trace :: proc(w: io.Writer, code: []Opcode) {
+	jump_targets := get_jump_targets(code)
+	defer delete(jump_targets)
+
+	iter := virtual_machine.Opcode_Iterator{ code, 0 }
+	for opcode, pc in virtual_machine.iterate_opcodes(&iter) {
+		if src, ok := jump_targets[pc]; ok {
+			io.write_string(w, "--")
+			common.write_padded_hex(w, src, 4)
+			io.write_string(w, "--> ")
+		} else {
+			io.write_string(w, "            ")
+		}
+
+		io.write_string(w, "[PC: ")
+		common.write_padded_hex(w, pc, 4)
+		io.write_string(w, "] ")
+		io.write_string(w, virtual_machine.opcode_to_name(opcode))
+		io.write_byte(w, ' ')
+
+		#partial switch opcode {
+		case .Byte:
+			operand := cast(rune)code[pc+1]
+			io.write_encoded_rune(w, operand)
+		case .Rune:
+			operand := (cast(^rune)&code[pc+1])^
+			io.write_encoded_rune(w, operand)
+		case .Rune_Class, .Rune_Class_Negated:
+			operand := cast(u8)code[pc+1]
+			common.write_padded_hex(w, operand, 2)
+		case .Jump:
+			jmp   := (cast(^u16)&code[pc+1])^
+			io.write_string(w, "-> $")
+			common.write_padded_hex(w, jmp, 4)
+		case .Split:
+			jmp_x := (cast(^u16)&code[pc+1])^
+			jmp_y := (cast(^u16)&code[pc+3])^
+			io.write_string(w, "=> $")
+			common.write_padded_hex(w, jmp_x, 4)
+			io.write_string(w, ", $")
+			common.write_padded_hex(w, jmp_y, 4)
+		case .Save:
+			operand := cast(u8)code[pc+1]
+			common.write_padded_hex(w, operand, 2)
+		case .Wait_For_Byte:
+			operand := cast(rune)code[pc+1]
+			io.write_encoded_rune(w, operand)
+		case .Wait_For_Rune:
+			operand := (cast(^rune)&code[pc+1])^
+			io.write_encoded_rune(w, operand)
+		case .Wait_For_Rune_Class:
+			operand := cast(u8)code[pc+1]
+			common.write_padded_hex(w, operand, 2)
+		case .Wait_For_Rune_Class_Negated:
+			operand := cast(u8)code[pc+1]
+			common.write_padded_hex(w, operand, 2)
+		}
+
+		io.write_byte(w, '\n')
+	}
+}