From: Michael Beck Date: Wed, 18 Jun 2008 10:07:59 +0000 (+0000) Subject: - removed old if 0'ed code X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=c2ead6606a9c2f318a628b152ec0ce16cbbe4483;p=libfirm - removed old if 0'ed code - add some doxygen comments [r20144] --- diff --git a/ir/be/ia32/ia32_optimize.c b/ir/be/ia32/ia32_optimize.c index b9c1c732b..f67ae7e19 100644 --- a/ir/be/ia32/ia32_optimize.c +++ b/ir/be/ia32/ia32_optimize.c @@ -61,96 +61,27 @@ DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;) static const arch_env_t *arch_env; static ia32_code_gen_t *cg; -#if 0 -static void peephole_ia32_Store_IncSP_to_push(ir_node *node) -{ - ir_node *base = get_irn_n(node, n_ia32_Store_base); - ir_node *index = get_irn_n(node, n_ia32_Store_index); - ir_node *mem = get_irn_n(node, n_ia32_Store_mem); - ir_node *incsp = base; - ir_node *val; - ir_node *noreg; - ir_graph *irg; - ir_node *block; - dbg_info *dbgi; - ir_mode *mode; - ir_node *push; - ir_node *proj; - int offset; - int node_offset; - - /* nomem inidicates the store doesn't alias with anything else */ - if(!is_NoMem(mem)) - return; - - /* find an IncSP in front of us, we might have to skip barriers for this */ - while(is_Proj(incsp)) { - ir_node *proj_pred = get_Proj_pred(incsp); - if(!be_is_Barrier(proj_pred)) - return; - incsp = get_irn_n(proj_pred, get_Proj_proj(incsp)); - } - if(!be_is_IncSP(incsp)) - return; - - be_peephole_IncSP_IncSP(incsp); - - /* must be in the same block */ - if(get_nodes_block(incsp) != get_nodes_block(node)) - return; - - if(!is_ia32_NoReg_GP(index) || get_ia32_am_sc(node) != NULL) { - panic("Invalid storeAM found (%+F)", node); - } - - /* we should be the store to the end of the stackspace */ - offset = be_get_IncSP_offset(incsp); - mode = get_ia32_ls_mode(node); - node_offset = get_ia32_am_offs_int(node); - if(node_offset != offset - get_mode_size_bytes(mode)) - return; - - /* we can use a push instead of the store */ - irg = current_ir_graph; - block = get_nodes_block(node); - dbgi = get_irn_dbg_info(node); - noreg = ia32_new_NoReg_gp(cg); - base = be_get_IncSP_pred(incsp); - val = get_irn_n(node, n_ia32_Store_val); - push = new_rd_ia32_Push(dbgi, irg, block, noreg, noreg, mem, val, base); - - proj = new_r_Proj(irg, block, push, mode_M, pn_ia32_Push_M); - - be_set_IncSP_offset(incsp, offset - get_mode_size_bytes(mode)); - - sched_add_before(node, push); - sched_remove(node); - - be_peephole_before_exchange(node, proj); - exchange(node, proj); - be_peephole_after_exchange(proj); -} - -static void peephole_ia32_Store(ir_node *node) -{ - peephole_ia32_Store_IncSP_to_push(node); -} -#endif - +/** + * Returns non-zero if the given node produces + * a zero flag. + * + * @param node the node to check + * @param pn if >= 0, the projection number of the used result + */ static int produces_zero_flag(ir_node *node, int pn) { ir_node *count; const ia32_immediate_attr_t *imm_attr; - if(!is_ia32_irn(node)) + if (!is_ia32_irn(node)) return 0; - if(pn >= 0) { - if(pn != pn_ia32_res) + if (pn >= 0) { + if (pn != pn_ia32_res) return 0; } - switch(get_ia32_irn_opcode(node)) { + switch (get_ia32_irn_opcode(node)) { case iro_ia32_Add: case iro_ia32_Adc: case iro_ia32_And: @@ -171,20 +102,20 @@ static int produces_zero_flag(ir_node *node, int pn) assert(n_ia32_ShlD_count == n_ia32_ShrD_count); assert(n_ia32_Shl_count == n_ia32_Shr_count && n_ia32_Shl_count == n_ia32_Sar_count); - if(is_ia32_ShlD(node) || is_ia32_ShrD(node)) { + if (is_ia32_ShlD(node) || is_ia32_ShrD(node)) { count = get_irn_n(node, n_ia32_ShlD_count); } else { count = get_irn_n(node, n_ia32_Shl_count); } /* when shift count is zero the flags are not affected, so we can only * do this for constants != 0 */ - if(!is_ia32_Immediate(count)) + if (!is_ia32_Immediate(count)) return 0; imm_attr = get_ia32_immediate_attr_const(count); - if(imm_attr->symconst != NULL) + if (imm_attr->symconst != NULL) return 0; - if((imm_attr->offset & 0x1f) == 0) + if ((imm_attr->offset & 0x1f) == 0) return 0; return 1; @@ -194,6 +125,13 @@ static int produces_zero_flag(ir_node *node, int pn) return 0; } +/** + * If the given node has not mode_T, creates a mode_T version (with a result Proj). + * + * @param node the node to change + * + * @return the new mode_T node (if the mode was changed) or node itself + */ static ir_node *turn_into_mode_t(ir_node *node) { ir_node *block; @@ -225,16 +163,21 @@ static ir_node *turn_into_mode_t(ir_node *node) return new_node; } +/** + * Peephole optimization for Test instructions. + * We can remove the Test, if a zero flags was produced which is still + * live. + */ static void peephole_ia32_Test(ir_node *node) { - ir_node *left = get_irn_n(node, n_ia32_Test_left); - ir_node *right = get_irn_n(node, n_ia32_Test_right); - ir_node *flags_proj; - ir_node *block; - ir_mode *flags_mode; - int pn = -1; - ir_node *schedpoint; - const ir_edge_t *edge; + ir_node *left = get_irn_n(node, n_ia32_Test_left); + ir_node *right = get_irn_n(node, n_ia32_Test_right); + ir_node *flags_proj; + ir_node *block; + ir_mode *flags_mode; + int pn = -1; + ir_node *schedpoint; + const ir_edge_t *edge; assert(n_ia32_Test_left == n_ia32_Test8Bit_left && n_ia32_Test_right == n_ia32_Test8Bit_right); @@ -360,7 +303,7 @@ static void peephole_ia32_Return(ir_node *node) { #define MAXPUSH_OPTIMIZE 48 /** - * Tries to create pushs from IncSP,Store combinations. + * Tries to create Push's from IncSP, Store combinations. * The Stores are replaced by Push's, the IncSP is modified * (possibly into IncSP 0, but not removed). */ @@ -567,7 +510,7 @@ static ir_node *create_push(dbg_info *dbgi, ir_graph *irg, ir_node *block, } /** - * Optimize an IncSp by replacing it with push/pop + * Optimize an IncSp by replacing it with Push/Pop. */ static void peephole_be_IncSP(ir_node *node) { @@ -965,7 +908,6 @@ 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_ia32_Store, peephole_ia32_Store); 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);