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From-SVN: r9887
This commit is contained in:
Jim Wilson 1995-06-06 10:45:43 -07:00
parent 79b2746ad7
commit 85256f8a68
1 changed files with 17 additions and 0 deletions
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17
gcc/config/sh/sh.h
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@ -56,6 +56,9 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
call_used_regs[MACL_REG] = 0; \
}
/* ??? Need to write documentation for all SH options and add it to the
invoke.texi file. */
/* Run-time compilation parameters selecting different hardware subsets. */
extern int target_flags;
@ -206,6 +209,9 @@ do { \
/* Allocation boundary (in *bits*) for the code of a function.
32 bit alignment is faster, because instructions are always fetched as a
pair from a longword boundary. */
/* ??? Perhaps also define ASM_OUTPUT_ALIGN_CODE and/or ASM_OUTPUT_LOOP_ALIGN
so as to align jump targets and/or loops to 4 byte boundaries when not
optimizing for space? */
#define FUNCTION_BOUNDARY (TARGET_SMALLCODE ? 16 : 32)
/* Alignment of field after `int : 0' in a structure. */
@ -972,6 +978,13 @@ extern int current_function_anonymous_args;
that the native compiler puts too large (> 32) immediate shift counts
into a register and shifts by the register, letting the SH decide what
to do instead of doing that itself. */
/* ??? This is defined, but the library routines in lib1funcs.asm do not
truncate the shift count. This may result in incorrect results for
unusual cases. Truncating the shift counts in the library routines would
make them faster. However, the SH3 has hardware shifts that do not
truncate, so it appears that we need to leave this undefined for correct
SH3 code. We can still using truncation in the library routines though to
make them faster. */
#define SHIFT_COUNT_TRUNCATED 1
/* All integers have the same format so truncation is easy. */
@ -1065,6 +1078,10 @@ extern int current_function_anonymous_args;
#define REGISTER_MOVE_COST(SRCCLASS, DSTCLASS) \
(((DSTCLASS == T_REGS) || (DSTCLASS == PR_REG)) ? 10 : 1)
/* ??? Perhaps make MEMORY_MOVE_COST depend on compiler option? This
would be so that people would slow memory systems could generate
different code that does fewer memory accesses. */
/* Assembler output control. */