ASL+

the latest iASL compiler (ver20141107) implements an extension support for symbolic (C-style) operations for math and logical expressions, so ASL code can be more humanity. ASL with these language extensions is called ASL+.

ASL+ compatible with legacy AML interpreters, no need new AML opcodes, compiler transforms expressions into legacy ASL/AML equivalents at compile time.

ASL+ Syntax	Legacy ASL Equivalent

// Math operators
Z = X + Y	Add (X, Y, Z)
Z = X - Y	Subtract (X, Y, Z)
Z = X * Y	Multiply (X, Y, Z)
Z = X / Y	Divide (X, Y, , Z)
Z = X % Y	Mod (X, Y, Z)

Z = X << Y	ShiftLeft (X, Y, Z)
Z = X >> Y	ShiftRight (X, Y, Z)

Z = X & Y	And (X, Y, Z)
Z = X | Y	Or (X, Y, Z)
Z = X ^ Y	Xor (X, Y, Z)
Z = ~X 		Not (X, Z)

X++		Increment (X)
X--		Decrement (X)

// Logical operators
(X == Y)	LEqual (X, Y)
(X != Y)	LNotEqual (X, Y)
(X < Y)		LLess (X, Y)
(X > Y)		LGreater (X, Y)
(X <= Y)	LLessEqual (X, Y)
(X >= Y)	LGreaterEqual (X, Y)
(X && Y)	LAnd (X, Y)
(X || Y)	LOr (X, Y)
(!X)		LNot (X)

// Compound assignment operations
X = Y		Store (Y, X)
X += Y		Add (X, Y, X)
X -= Y		Subtract (X, Y, X)
X *= Y		Multiply (X, Y, X)
X /= Y		Divide (X, Y, , X)
X %= Y		Mod (X, Y, X)
X <<= Y		ShiftLeft (X, Y, X)
X >>= Y		ShiftRight (X, Y, X)
X &= Y		And (X, Y, X)
X |= Y		Or (X, Y, X)
X ^= Y		Xor (X, Y, X)

Verify and Test

Let’s test this with coreboot acpi code:
*1. copy “coreboot\src\arch\x86\acpi\debug.asl” to a test folder
*2. create a test.asl in the same folder, content as below

DefinitionBlock ( "DSDT.AML", "DSDT", 0x01, "XXXXXX", "XXXXXXXX", 0x00010001 ) { #include "debug.asl" }

*3. modify line 122 add(Local0, 0x37, Local0) to Local0 += 0x37
*4. compile with iASL ver20141107 and iASL ver20130927, check out the differences.

D:\test>iasl test.asl

Intel ACPI Component Architecture
ASL+ Optimizing Compiler version 20141107-32 [Nov  7 2014]
Copyright (c) 2000 - 2014 Intel Corporation

debug.asl    166: ethod(DBGO, 1)
Remark   2120 -            ^ Control Method should be made Serialized (due to cr
eation of named objects within)

ASL Input:     test.asl - 13 lines, 1571 bytes, 59 keywords
AML Output:    DSDT.aml - 443 bytes, 16 named objects, 43 executable opcodes

Compilation complete. 0 Errors, 0 Warnings, 1 Remarks, 10 Optimizations

D:\test>iasl20130927 test.asl

Intel ACPI Component Architecture
ASL Optimizing Compiler version 20130927-32 [Sep 27 2013]
Copyright (c) 2000 - 2013 Intel Corporation

Compiler aborting due to parser-detected syntax error(s)
debug.asl    123:        Local0 += 0x37
Error    6126 -               ^ syntax error, unexpected PARSEOP_LOCAL0

debug.asl    123:        Local0 += 0x37
Error    6126 -                 ^ Invalid character (0x2B), expecting ASL keywor
d or name

debug.asl    123:        Local0 += 0x37
Error    6126 -                  ^ Invalid character (0x3D), expecting ASL keywo
rd or name

ASL Input:     test.asl - 12 lines, 1561 bytes, 57 keywords

Compilation complete. 3 Errors, 0 Warnings, 0 Remarks, 0 Optimizations