Epson S5U1C17001C, Manual

Page: 374 / 742

6-8
EPSOn
S5U1C17001C ManUal
(C COMPilEr PaCkagE fOr S1C17 faMily) (Ver. 1.5.0)
6 C COMPilEr
6.4 Compiler Output
This section explains the assembly sources output by the
xgcc
C compiler and the registers used by the
xgcc
.
6.4.1 Output Contents
After compiling C sources, the xgcc C compiler outputs the following contents:
• S1C17 Core instruction set mnemonics
• Extended instruction mnemonics
• Assembler directives
All but the basic instructions are output using extended instructions.
Since the system control instructions cannot be expressed in the C source, use in-line assemble by
asm
or an
assembly source file to process them.
Example:
asm("halt");
Assembler directives are output for section and data definitions.
The following describes the sections where instructions and data are set.
instructions
All instructions are located in the
.text
section.
Constants
Constants are located in the
.rodata
section.
Example:
const int i=1; .global i
.section .rodata
.align 2
.type i,@object
.size i,4
i:
.long 1
global and static variables with initial values
These variables are located in the
.data
section.
Example:
int i=1; .global i
.section .data
.align 2
.type i,@object
.size i,4
i:
.long 1
global and static variables without initial values
These variables are located in the
.bss
section.
Example:
int i; .global i
.section .bss
.align 2
.type i,@object
.size i,4
i:
.zero 4
For all symbols including function names and labels, symbol information by the
.stab
assembler directive is
inserted (when the
-gstabs
option is specified).