Commit 0506d9b4 authored by Christian Würdig's avatar Christian Würdig
Browse files

added peephole optimization for test/cmp

parent cbab525f
......@@ -487,6 +487,9 @@ static void ia32_finish_irg_walker(ir_node *irn, void *env) {
/* transform a LEA into an Add if possible */
ia32_transform_lea_to_add(irn, cg);
/* check for peephole optimization */
ia32_peephole_optimization(irn, cg);
}
/**
......
......@@ -665,6 +665,7 @@ static void TestJmp_emitter(const ir_node *irn, ia32_emit_env_t *env) {
snprintf(cmd_buf, SNPRINTF_BUF_LEN, "test %%%s,%s%s ", op1, get_ia32_cnst(irn) ? " " : " %", op2);
lc_esnprintf(ia32_get_arg_env(), cmnt_buf, SNPRINTF_BUF_LEN, "/* %+F */", irn);
IA32_DO_EMIT;
finish_CondJmp(F, irn, get_irn_mode(get_irn_n(irn, 0)));
}
......@@ -676,7 +677,27 @@ static void emit_ia32_TestJmp(const ir_node *irn, ia32_emit_env_t *env) {
TestJmp_emitter(irn, env);
}
static void emit_ia32_CJmp(const ir_node *irn, ia32_emit_env_t *env) {
FILE *F = env->out;
char cmd_buf[SNPRINTF_BUF_LEN];
char cmnt_buf[SNPRINTF_BUF_LEN];
snprintf(cmd_buf, SNPRINTF_BUF_LEN, " ");
lc_esnprintf(ia32_get_arg_env(), cmnt_buf, SNPRINTF_BUF_LEN, "/* %+F omitted redundant test/cmp */", irn);
IA32_DO_EMIT;
finish_CondJmp(F, irn, get_irn_mode(get_irn_n(irn, 0)));
}
static void emit_ia32_CJmpAM(const ir_node *irn, ia32_emit_env_t *env) {
FILE *F = env->out;
char cmd_buf[SNPRINTF_BUF_LEN];
char cmnt_buf[SNPRINTF_BUF_LEN];
snprintf(cmd_buf, SNPRINTF_BUF_LEN, " ");
lc_esnprintf(ia32_get_arg_env(), cmnt_buf, SNPRINTF_BUF_LEN, "/* %+F omitted redundant test/cmp */", irn);
IA32_DO_EMIT;
finish_CondJmp(F, irn, get_irn_mode(get_irn_n(irn, 2)));
}
/*********************************************************
* _ _ _
......@@ -1238,6 +1259,8 @@ static void ia32_register_emitters(void) {
/* other ia32 emitter functions */
IA32_EMIT(CondJmp);
IA32_EMIT(TestJmp);
IA32_EMIT(CJmp);
IA32_EMIT(CJmpAM);
IA32_EMIT(SwitchJmp);
IA32_EMIT(CopyB);
IA32_EMIT(CopyB_i);
......
......@@ -22,6 +22,8 @@
#undef is_NoMem
#define is_NoMem(irn) (get_irn_op(irn) == op_NoMem)
typedef int *is_op_func_t(const ir_node *n);
static int be_is_NoReg(be_abi_irg_t *babi, const ir_node *irn) {
if (be_abi_get_callee_save_irn(babi, &ia32_gp_regs[REG_XXX]) == irn ||
be_abi_get_callee_save_irn(babi, &ia32_fp_regs[REG_XXXX]) == irn)
......@@ -32,6 +34,18 @@ static int be_is_NoReg(be_abi_irg_t *babi, const ir_node *irn) {
return 0;
}
/*************************************************
* _____ _ _
* / ____| | | | |
* | | ___ _ __ ___| |_ __ _ _ __ | |_ ___
* | | / _ \| '_ \/ __| __/ _` | '_ \| __/ __|
* | |___| (_) | | | \__ \ || (_| | | | | |_\__ \
* \_____\___/|_| |_|___/\__\__,_|_| |_|\__|___/
*
*************************************************/
/**
* creates a unique ident by adding a number to a tag
*
......@@ -226,6 +240,169 @@ void ia32_place_consts_set_modes(ir_node *irn, void *env) {
}
/********************************************************************************************************
* _____ _ _ ____ _ _ _ _ _
* | __ \ | | | | / __ \ | | (_) (_) | | (_)
* | |__) |__ ___ _ __ | |__ ___ | | ___ | | | |_ __ | |_ _ _ __ ___ _ ______ _| |_ _ ___ _ __
* | ___/ _ \/ _ \ '_ \| '_ \ / _ \| |/ _ \ | | | | '_ \| __| | '_ ` _ \| |_ / _` | __| |/ _ \| '_ \
* | | | __/ __/ |_) | | | | (_) | | __/ | |__| | |_) | |_| | | | | | | |/ / (_| | |_| | (_) | | | |
* |_| \___|\___| .__/|_| |_|\___/|_|\___| \____/| .__/ \__|_|_| |_| |_|_/___\__,_|\__|_|\___/|_| |_|
* | | | |
* |_| |_|
********************************************************************************************************/
/**
* NOTE: THESE PEEPHOLE OPTIMIZATIONS MUST BE CALLED AFTER SCHEDULING AND REGISTER ALLOCATION.
*/
static int ia32_cnst_compare(ir_node *n1, ir_node *n2) {
char *c1 = get_ia32_cnst(n1);
char *c2 = get_ia32_cnst(n2);
if (c1 && c2) /* both consts are set -> compare */
return strcmp(c1, c2) == 0;
else if (!c1 && !c2) /* both consts are not set -> true */
return 1;
return 0;
}
/**
* Checks for potential CJmp/CJmpAM optimization candidates.
*/
static ir_node *ia32_determine_cjmp_cand(ir_node *irn, is_op_func_t *is_op_func) {
ir_node *cand = NULL;
ir_node *prev = sched_prev(irn);
if (is_Block(prev)) {
if (get_Block_n_cfgpreds(prev) == 1)
prev = get_Block_cfgpred(prev, 0);
else
prev = NULL;
}
/* The predecessor must be a ProjX. */
if (prev && is_Proj(prev) && get_irn_mode(prev) == mode_X) {
prev = get_Proj_pred(prev);
if (is_op_func(prev))
cand = prev;
}
return cand;
}
static int is_TestJmp_cand(const ir_node *irn) {
return is_ia32_TestJmp(irn) || is_ia32_And(irn);
}
/**
* Checks if two consecutive arguments of cand matches
* the two arguments of irn (TestJmp).
*/
static int is_TestJmp_replacement(ir_node *cand, ir_node *irn) {
ir_node *in1 = get_irn_n(irn, 0);
ir_node *in2 = get_irn_n(irn, 1);
int i, n = get_irn_arity(cand);
int same_args = 0;
char *c1, *c2;
for (i = 0; i < n - 1; i++) {
if (get_irn_n(cand, i) == in1 &&
get_irn_n(cand, i + 1) == in2)
{
same_args = 1;
break;
}
}
if (same_args)
return ia32_cnst_compare(cand, irn);
return 0;
}
/**
* Tries to replace a TestJmp by a CJmp or CJmpAM (in case of And)
*/
static void ia32_optimize_TestJmp(ir_node *irn, ia32_code_gen_t *cg) {
ir_node *cand = ia32_determine_cjmp_cand(irn, is_TestJmp_cand);
int replace = 0;
/* we found a possible candidate */
replace = cand ? is_TestJmp_replacement(cand, irn) : 0;
if (replace) {
DBG((cg->mod, LEVEL_1, "replacing %+F by ", irn));
if (is_ia32_And(cand))
set_irn_op(irn, op_ia32_CJmpAM);
else
set_irn_op(irn, op_ia32_CJmp);
DB((cg->mod, LEVEL_1, "%+F\n", irn));
}
}
static int is_CondJmp_cand(const ir_node *irn) {
return is_ia32_CondJmp(irn) || is_ia32_Sub(irn);
}
/**
* Checks if the arguments of cand are the same of irn.
*/
static int is_CondJmp_replacement(ir_node *cand, ir_node *irn) {
int i, n = get_irn_arity(cand);
int same_args = 0;
char *c1, *c2;
for (i = 0; i < n; i++) {
if (get_irn_n(cand, i) == get_irn_n(irn, i)) {
same_args = 1;
break;
}
}
if (same_args)
return ia32_cnst_compare(cand, irn);
return 0;
}
/**
* Tries to replace a CondJmp by a CJmpAM
*/
static void ia32_optimize_CondJmp(ir_node *irn, ia32_code_gen_t *cg) {
ir_node *cand = ia32_determine_cjmp_cand(irn, is_CondJmp_cand);
int replace = 0;
/* we found a possible candidate */
replace = cand ? is_CondJmp_replacement(cand, irn) : 0;
if (replace) {
DBG((cg->mod, LEVEL_1, "replacing %+F by ", irn));
set_irn_op(irn, op_ia32_CJmp);
DB((cg->mod, LEVEL_1, "%+F\n", irn));
}
}
/**
* Performs Peephole Optimizations
*/
void ia32_peephole_optimization(ir_node *irn, void *env) {
if (is_ia32_TestJmp(irn)) {
ia32_optimize_TestJmp(irn, env);
}
else if (is_ia32_CondJmp(irn)) {
ia32_optimize_CondJmp(irn, env);
}
}
/******************************************************************
* _ _ __ __ _
* /\ | | | | | \/ | | |
......@@ -300,7 +477,7 @@ static ir_node *get_res_proj(const ir_node *irn) {
* @param is_op_func The check-function
* @return 1 if conditions are fulfilled, 0 otherwise
*/
static int pred_is_specific_node(const ir_node *pred, int (*is_op_func)(const ir_node *n)) {
static int pred_is_specific_node(const ir_node *pred, is_op_func_t *is_op_func) {
if (is_Proj(pred) && is_op_func(get_Proj_pred(pred))) {
return 1;
}
......
......@@ -16,4 +16,10 @@ void ia32_place_consts_set_modes(ir_node *irn, void *env);
*/
void ia32_optimize_am(ir_node *irn, void *env);
/**
* Performs Peephole Optimizations
* This function is called by a walker.
*/
void ia32_peephole_optimization(ir_node *irn, void *env);
#endif /* _IA32_OPTIMIZE_H_ */
......@@ -344,14 +344,28 @@ $comment_string = "/*";
"op_flags" => "L|X|Y",
"comment" => "construct conditional jump: CMP A, B && JMPxx LABEL",
"cmp_attr" => " return ia32_compare_immop_attr(attr_a, attr_b);\n",
"reg_req" => { "in" => [ "gp", "gp", "gp", "gp", "none" ], "out" => [ "none", "none" ] },
"reg_req" => { "in" => [ "gp", "gp", "gp", "gp", "none" ] },
},
"TestJmp" => {
"op_flags" => "L|X|Y",
"comment" => "construct conditional jump: TEST A, B && JMPxx LABEL",
"reg_req" => { "in" => [ "gp", "gp" ], "out" => [ "none", "none" ] },
"reg_req" => { "in" => [ "gp", "gp" ] },
"cmp_attr" => " return ia32_compare_immop_attr(attr_a, attr_b);\n",
},
"CJmpAM" => {
"op_flags" => "L|X|Y",
"comment" => "construct conditional jump without CMP (replaces CondJmp): JMPxx LABEL",
"cmp_attr" => " return ia32_compare_immop_attr(attr_a, attr_b);\n",
"reg_req" => { "in" => [ "gp", "gp", "gp", "gp", "none" ], "out" => [ "none", "none" ] },
},
"CJmp" => {
"op_flags" => "L|X|Y",
"comment" => "construct conditional jump without CMP (replaces TestJmp): JMPxx LABEL",
"cmp_attr" => " return ia32_compare_immop_attr(attr_a, attr_b);\n",
"reg_req" => { "in" => [ "gp", "gp" ] },
},
"SwitchJmp" => {
......
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