Small simplification in ia32 ASM emitter.

[libfirm] / ir / be / ia32 / ia32_optimize.c

diff --git a/ir/be/ia32/ia32_optimize.c b/ir/be/ia32/ia32_optimize.c
index fc08bf7..341437c 100644 (file)
--- a/ir/be/ia32/ia32_optimize.c
+++ b/ir/be/ia32/ia32_optimize.c
@@ -160,6 +160,71 @@ static ir_node *turn_into_mode_t(ir_node *node)
        return new_node;
 }
 
+/**
+ * Replace Cmp(x, 0) by a Test(x, x)
+ */
+static void peephole_ia32_Cmp(ir_node *const node)
+{
+       ir_node                     *right;
+       ia32_immediate_attr_t const *imm;
+       dbg_info                    *dbgi;
+       ir_graph                    *irg;
+       ir_node                     *block;
+       ir_node                     *noreg;
+       ir_node                     *nomem;
+       ir_node                     *op;
+       ia32_attr_t           const *attr;
+       int                          ins_permuted;
+       int                          cmp_unsigned;
+       ir_node                     *test;
+       arch_register_t       const *reg;
+       ir_edge_t             const *edge;
+       ir_edge_t             const *tmp;
+
+       if (get_ia32_op_type(node) != ia32_Normal)
+               return;
+
+       right = get_irn_n(node, n_ia32_Cmp_right);
+       if (!is_ia32_Immediate(right))
+               return;
+
+       imm = get_ia32_immediate_attr_const(right);
+       if (imm->symconst != NULL || imm->offset != 0)
+               return;
+
+       dbgi         = get_irn_dbg_info(node);
+       irg          = current_ir_graph;
+       block        = get_nodes_block(node);
+       noreg        = ia32_new_NoReg_gp(cg);
+       nomem        = get_irg_no_mem(irg);
+       op           = get_irn_n(node, n_ia32_Cmp_left);
+       attr         = get_irn_generic_attr(node);
+       ins_permuted = attr->data.ins_permuted;
+       cmp_unsigned = attr->data.cmp_unsigned;
+
+       if (is_ia32_Cmp(node)) {
+               test = new_rd_ia32_Test(dbgi, irg, block, noreg, noreg, nomem,
+                                       op, op, ins_permuted, cmp_unsigned);
+       } else {
+               test = new_rd_ia32_Test8Bit(dbgi, irg, block, noreg, noreg, nomem,
+                                           op, op, ins_permuted, cmp_unsigned);
+       }
+       set_ia32_ls_mode(test, get_ia32_ls_mode(node));
+
+       reg = arch_get_irn_register(arch_env, node);
+       arch_set_irn_register(arch_env, test, reg);
+
+       foreach_out_edge_safe(node, edge, tmp) {
+               ir_node *const user = get_edge_src_irn(edge);
+
+               if (is_Proj(user))
+                       exchange(user, test);
+       }
+
+       sched_add_before(node, test);
+       be_peephole_exchange(node, test);
+}
+
 /**
  * Peephole optimization for Test instructions.
  * We can remove the Test, if a zero flags was produced which is still
@@ -1046,12 +1111,14 @@ void ia32_peephole_optimization(ia32_code_gen_t *new_cg)
 
        /* register peephole optimisations */
        clear_irp_opcodes_generic_func();
-       register_peephole_optimisation(op_ia32_Const, peephole_ia32_Const);
-       register_peephole_optimisation(op_be_IncSP, peephole_be_IncSP);
-       register_peephole_optimisation(op_ia32_Lea, peephole_ia32_Lea);
-       register_peephole_optimisation(op_ia32_Test, peephole_ia32_Test);
+       register_peephole_optimisation(op_ia32_Const,    peephole_ia32_Const);
+       register_peephole_optimisation(op_be_IncSP,      peephole_be_IncSP);
+       register_peephole_optimisation(op_ia32_Lea,      peephole_ia32_Lea);
+       register_peephole_optimisation(op_ia32_Cmp,      peephole_ia32_Cmp);
+       register_peephole_optimisation(op_ia32_Cmp8Bit,  peephole_ia32_Cmp);
+       register_peephole_optimisation(op_ia32_Test,     peephole_ia32_Test);
        register_peephole_optimisation(op_ia32_Test8Bit, peephole_ia32_Test);
-       register_peephole_optimisation(op_be_Return, peephole_ia32_Return);
+       register_peephole_optimisation(op_be_Return,     peephole_ia32_Return);
        if (! ia32_cg_config.use_imul_mem_imm32)
                register_peephole_optimisation(op_ia32_IMul, peephole_ia32_Imul_split);
        if (ia32_cg_config.use_pxor)