diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 63ba525d08a..2d110110545 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2011-05-29 Richard Sandiford + + PR target/43995 + * config/mips/mips.c (mips_pic_call_symbol_from_set): Add a + recurse_p argument. Only follow register copies if it is set, + and prevent mips_find_pic_call_symbol from recursing. + (mips_find_pic_call_symbol): Add a recurse_p argument. + Pass it to mips_pic_call_symbol_from_set. + (mips_annotate_pic_calls): Update accordingly. + 2011-05-29 Richard Sandiford * emit-rtl.c (try_split): Use a loop to search for diff --git a/gcc/config/mips/mips.c b/gcc/config/mips/mips.c index 46b25f7b985..39042386930 100644 --- a/gcc/config/mips/mips.c +++ b/gcc/config/mips/mips.c @@ -1060,7 +1060,7 @@ static const struct mips_rtx_cost_data } }; -static rtx mips_find_pic_call_symbol (rtx, rtx); +static rtx mips_find_pic_call_symbol (rtx, rtx, bool); static int mips_register_move_cost (enum machine_mode, reg_class_t, reg_class_t); static unsigned int mips_function_arg_boundary (enum machine_mode, const_tree); @@ -14026,12 +14026,16 @@ mips_call_expr_from_insn (rtx insn, rtx *second_call) } /* REG is set in DEF. See if the definition is one of the ways we load a - register with a symbol address for a mips_use_pic_fn_addr_reg_p call. If - it is return the symbol reference of the function, otherwise return - NULL_RTX. */ + register with a symbol address for a mips_use_pic_fn_addr_reg_p call. + If it is, return the symbol reference of the function, otherwise return + NULL_RTX. + + If RECURSE_P is true, use mips_find_pic_call_symbol to interpret + the values of source registers, otherwise treat such registers as + having an unknown value. */ static rtx -mips_pic_call_symbol_from_set (df_ref def, rtx reg) +mips_pic_call_symbol_from_set (df_ref def, rtx reg, bool recurse_p) { rtx def_insn, set; @@ -14058,21 +14062,39 @@ mips_pic_call_symbol_from_set (df_ref def, rtx reg) return symbol; } - /* Follow simple register copies. */ - if (REG_P (src)) - return mips_find_pic_call_symbol (def_insn, src); + /* Follow at most one simple register copy. Such copies are + interesting in cases like: + + for (...) + { + locally_binding_fn (...); + } + + and: + + locally_binding_fn (...); + ... + locally_binding_fn (...); + + where the load of locally_binding_fn can legitimately be + hoisted or shared. However, we do not expect to see complex + chains of copies, so a full worklist solution to the problem + would probably be overkill. */ + if (recurse_p && REG_P (src)) + return mips_find_pic_call_symbol (def_insn, src, false); } return NULL_RTX; } -/* Find the definition of the use of REG in INSN. See if the definition is - one of the ways we load a register with a symbol address for a - mips_use_pic_fn_addr_reg_p call. If it is return the symbol reference of - the function, otherwise return NULL_RTX. */ +/* Find the definition of the use of REG in INSN. See if the definition + is one of the ways we load a register with a symbol address for a + mips_use_pic_fn_addr_reg_p call. If it is return the symbol reference + of the function, otherwise return NULL_RTX. RECURSE_P is as for + mips_pic_call_symbol_from_set. */ static rtx -mips_find_pic_call_symbol (rtx insn, rtx reg) +mips_find_pic_call_symbol (rtx insn, rtx reg, bool recurse_p) { df_ref use; struct df_link *defs; @@ -14084,7 +14106,7 @@ mips_find_pic_call_symbol (rtx insn, rtx reg) defs = DF_REF_CHAIN (use); if (!defs) return NULL_RTX; - symbol = mips_pic_call_symbol_from_set (defs->ref, reg); + symbol = mips_pic_call_symbol_from_set (defs->ref, reg, recurse_p); if (!symbol) return NULL_RTX; @@ -14093,7 +14115,7 @@ mips_find_pic_call_symbol (rtx insn, rtx reg) { rtx other; - other = mips_pic_call_symbol_from_set (defs->ref, reg); + other = mips_pic_call_symbol_from_set (defs->ref, reg, recurse_p); if (!rtx_equal_p (symbol, other)) return NULL_RTX; } @@ -14164,7 +14186,7 @@ mips_annotate_pic_calls (void) if (!REG_P (reg)) continue; - symbol = mips_find_pic_call_symbol (insn, reg); + symbol = mips_find_pic_call_symbol (insn, reg, true); if (symbol) { mips_annotate_pic_call_expr (call, symbol);