diff options
| author | Jeff Garzik <jgarzik@redhat.com> | 2003-09-12 02:05:06 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-07 21:01:15 -0700 |
| commit | 1ff814445ad900b41ae5325a6a996f5575d499bd (patch) | |
| tree | 8eb5b80de3d19f426dd4786fdd0516208f168c17 /compile-i386.c | |
| parent | c17404ab0019bf20cbdc0ecbc298040a2af5e52a (diff) | |
| download | sparse-dev-1ff814445ad900b41ae5325a6a996f5575d499bd.tar.gz | |
[be] prefer "mov $0, %eax" to "xor %eax, %eax"
Diffstat (limited to 'compile-i386.c')
| -rw-r--r-- | compile-i386.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/compile-i386.c b/compile-i386.c index 4a5a1769..aab854e4 100644 --- a/compile-i386.c +++ b/compile-i386.c @@ -935,7 +935,7 @@ static struct storage *emit_compare(struct expression *expr) { struct storage *left = x86_expression(expr->left); struct storage *right = x86_expression(expr->right); - struct storage *new; + struct storage *new, *val; const char *opname = NULL; unsigned int is_signed = type_is_signed(expr->left->ctype); /* FIXME */ unsigned int right_bits = expr->right->ctype->bit_size; @@ -967,7 +967,9 @@ static struct storage *emit_compare(struct expression *expr) } /* init EDX to 0 */ - insn("xor", REG_EDX, REG_EDX, "begin EXPR_COMPARE"); + val = new_storage(STOR_VALUE); + val->flags = STOR_WANTS_FREE; + emit_move(val, REG_EDX, NULL, NULL); /* move op1 into EAX */ emit_move(left, REG_EAX, expr->left->ctype, NULL); @@ -1250,12 +1252,14 @@ static struct storage *emit_cast_expr(struct expression *expr) static struct storage *emit_regular_preop(struct expression *expr) { struct storage *target = x86_expression(expr->unop); - struct storage *new = new_pseudo(); + struct storage *val, *new = new_pseudo(); const char *opname = NULL; switch (expr->op) { case '!': - insn("xor", REG_EDX, REG_EDX, NULL); + val = new_storage(STOR_VALUE); + val->flags = STOR_WANTS_FREE; + emit_move(val, REG_EDX, NULL, NULL); emit_move(target, REG_EAX, expr->unop->ctype, NULL); insn("test", REG_EAX, REG_EAX, NULL); insn("setz", REG_DL, NULL, NULL); |