Use unaligned_load for regex virtual machine

This should hopefully avoid any issues with loading operands greater
than 8 bits on alignment-sensitive platforms.
This commit is contained in:
Feoramund
2024-07-24 16:27:20 -04:00
parent 042f6de478
commit ff492e615c
3 changed files with 21 additions and 18 deletions
+5 -4
View File
@@ -1,5 +1,6 @@
package regex_compiler
import "base:intrinsics"
import "core:text/regex/common"
import "core:text/regex/parser"
import "core:text/regex/tokenizer"
@@ -408,7 +409,7 @@ compile :: proc(tree: Node, flags: common.Flags) -> (code: Program, class_data:
break add_global
case .Rune:
operand := (cast(^rune)&code[pc+1])^
operand := intrinsics.unaligned_load(cast(^rune)&code[pc+1])
inject_at(&code, pc_open, Opcode.Wait_For_Rune)
pc_open += size_of(Opcode)
inject_raw(&code, pc_open, operand)
@@ -490,20 +491,20 @@ compile :: proc(tree: Node, flags: common.Flags) -> (code: Program, class_data:
case .Jump:
jmp := cast(^i16)&code[pc+size_of(Opcode)]
if code[cast(i16)pc+jmp^] == .Jump {
next_jmp := (cast(^i16)&code[cast(i16)pc+jmp^+size_of(Opcode)])^
next_jmp := intrinsics.unaligned_load(cast(^i16)&code[cast(i16)pc+jmp^+size_of(Opcode)])
jmp^ = jmp^ + next_jmp
do_another_pass = true
}
case .Split:
jmp_x := cast(^i16)&code[pc+size_of(Opcode)]
if code[cast(i16)pc+jmp_x^] == .Jump {
next_jmp := (cast(^i16)&code[cast(i16)pc+jmp_x^+size_of(Opcode)])^
next_jmp := intrinsics.unaligned_load(cast(^i16)&code[cast(i16)pc+jmp_x^+size_of(Opcode)])
jmp_x^ = jmp_x^ + next_jmp
do_another_pass = true
}
jmp_y := cast(^i16)&code[pc+size_of(Opcode)+size_of(i16)]
if code[cast(i16)pc+jmp_y^] == .Jump {
next_jmp := (cast(^i16)&code[cast(i16)pc+jmp_y^+size_of(Opcode)])^
next_jmp := intrinsics.unaligned_load(cast(^i16)&code[cast(i16)pc+jmp_y^+size_of(Opcode)])
jmp_y^ = jmp_y^ + next_jmp
do_another_pass = true
}
+8 -7
View File
@@ -1,5 +1,6 @@
package regex_compiler
import "base:intrinsics"
import "core:io"
import "core:text/regex/common"
import "core:text/regex/virtual_machine"
@@ -9,11 +10,11 @@ get_jump_targets :: proc(code: []Opcode) -> (jump_targets: map[int]int) {
for opcode, pc in virtual_machine.iterate_opcodes(&iter) {
#partial switch opcode {
case .Jump:
jmp := cast(int)(cast(^u16)&code[pc+1])^
jmp := cast(int)intrinsics.unaligned_load(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])^
jmp_x := cast(int)intrinsics.unaligned_load(cast(^u16)&code[pc+1])
jmp_y := cast(int)intrinsics.unaligned_load(cast(^u16)&code[pc+3])
jump_targets[jmp_x] = pc
jump_targets[jmp_y] = pc
}
@@ -46,18 +47,18 @@ trace :: proc(w: io.Writer, code: []Opcode) {
operand := cast(rune)code[pc+1]
io.write_encoded_rune(w, operand)
case .Rune:
operand := (cast(^rune)&code[pc+1])^
operand := intrinsics.unaligned_load(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])^
jmp := intrinsics.unaligned_load(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])^
jmp_x := intrinsics.unaligned_load(cast(^u16)&code[pc+1])
jmp_y := intrinsics.unaligned_load(cast(^u16)&code[pc+3])
io.write_string(w, "=> $")
common.write_padded_hex(w, jmp_x, 4)
io.write_string(w, ", $")