TC-X Code to Write

Tip

Information on IA-32 assembly instructions may be found in the Intel® 64 and IA-32 Architectures Software Developer Manuals, or in this much shorter IA32 Instruction List form.

The documentation of the GNU Assembler (GAS) is also a recommended reading.

src/target/ia32/gas-matcher.cc

target::ia32::GasMatcher is the functor used for instruction selection pattern-matching.

src/target/ia32/gas-assembly.cc

GasAssembly::cjump_build translates conditional branch instructions (branch if equal, if lower than, etc.) into IA-32 assembly.

Runtime

You have to complete the implementation of the runtime in src/target/ia32/runtime-gnu-linux.s:

strcmp

streq

Warning

Strings are implemented as 4 bytes to encode the length, and then a 0-terminated C-like string. You should rely on the initial encoded length, which is always present for compliance.

See the example below on how the string data is represented (l0):

hello-world-ia32.tig

print("Hello Tiger!")

tc --target-ia32 --inst-display hello-world-ia32.tig | head -n 6

$ tc --target-ia32 --inst-display hello-world-ia32.tig | head -n 6
/** Tiger final assembler ouput. */

	.section	.rodata
l0:
	.long 12
	.asciz "Hello Tiger!"
$ echo $?
0

String data representation (assuming little endian)

Address (l0 +)	0x00	0x01	0x02	0x03	0x04	0x05	…	0x10
Value	0x00	0x00	0x00	0x0c	'H'	'e'	…	'\0'

---

src/target/ia32/gas-codegen.cc (Optional)

Completing the Codegen::rewrite_program routine will be needed during register allocation only, see TC-9, Register Allocation.