Epson S5U1C17001C, Manual

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S5U1C17001C ManUal
EPSOn
7-3
(C COMPilEr PaCkagE fOr S1C17 faMily) (Ver. 1.5.0)
7 liBrary
7
Library
7.2 Emulation library
7.2.1 Overview
The S1C17 Family C Compiler Package includes the emulation library (
libgcc.a
,
libgccM.a
,
libgccMD.a
)
that supports the arithmetic operation, comparison, and type conversion of single-precision (32-bit) and double-
precision (64-bit) floating-point numbers that conform to IEEE format, integer multiplication/division/sift
operations, and
long long
-type addition/subtraction. The libgcc.a library does not use coprocessor instructions;
the libgccM.a library uses multiplication coprocessor instructions; the libgccMD.a library uses multiplication,
division, and remainder coprocessor instructions. These libraries provide the same functions. The
xgcc
C compiler
calls up functions from this library when a floating-point number,
long long
data or integer calculation is
performed. Since library functions exchange data via a designated general-purpose register/stack, they can be called
from an assembly source. To use emulation library functions, specify libgcc.a (
libgccM.a
,
libgccMD.a
) and
libc.a when linking.
registers used in the libraries
• The registers
%r0
to
%r7
are used.
• The registers
%r4
to
%r7
are protected by saving to the stack before execution of a function and by restoring
from the stack after completion of the function.