x86: added GNU GAS syntax, which is similar to AT&T syntax

include/keystone/keystone.h

@@ -139,7 +139,8 @@ typedef enum ks_opt_value {
 	KS_OPT_SYNTAX_INTEL = 1 << 0, // X86 Intel syntax - default on X86 (KS_OPT_SYNTAX).
 	KS_OPT_SYNTAX_ATT   = 1 << 1, // X86 ATT asm syntax (KS_OPT_SYNTAX).
 	KS_OPT_SYNTAX_NASM  = 1 << 2, // X86 Nasm syntax (KS_OPT_SYNTAX).
-	KS_OPT_SYNTAX_MASM  = 1 << 3, // X86 Masm syntax (KS_OPT_SYNTAX).
+	KS_OPT_SYNTAX_MASM  = 1 << 3, // X86 Masm syntax (KS_OPT_SYNTAX) - unsupported yet.
+	KS_OPT_SYNTAX_GAS   = 1 << 4, // X86 GAS syntax (KS_OPT_SYNTAX)
 } ks_opt_value;
 
 

llvm/keystone/ks.cpp

@@ -418,6 +418,7 @@ ks_err ks_option(ks_engine *ks, ks_opt_type type, size_t value)
                     ks->syntax = (ks_opt_value)value;
                     ks->MAI->setAssemblerDialect(1);
                     break;
+                case KS_OPT_SYNTAX_GAS:
                 case KS_OPT_SYNTAX_ATT:
                     ks->syntax = (ks_opt_value)value;
                     ks->MAI->setAssemblerDialect(0);