From f8a30250165a6dc9ac3e323cdf0859f13b4b69d8 Mon Sep 17 00:00:00 2001 From: Alexandre Oliva Date: Fri, 9 May 2003 17:16:54 +0000 Subject: [PATCH] reload1.c (reload_cse_move2add): Don't turn an implicit truncation into a self-set in the narrow mode. * reload1.c (reload_cse_move2add): Don't turn an implicit truncation into a self-set in the narrow mode. From-SVN: r66638 --- gcc/ChangeLog | 5 +++++ gcc/reload1.c | 21 +++++++++++++++++---- 2 files changed, 22 insertions(+), 4 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 01bc7fff725..d7ac8d830a7 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2003-05-09 Alexandre Oliva + + * reload1.c (reload_cse_move2add): Don't turn an implicit + truncation into a self-set in the narrow mode. + 2003-05-09 Richard Earnshaw * arm.md (clzsi2): The CLZ instruction is predicable. diff --git a/gcc/reload1.c b/gcc/reload1.c index 792dd467e89..adae5c8a162 100644 --- a/gcc/reload1.c +++ b/gcc/reload1.c @@ -9166,7 +9166,14 @@ reload_cse_move2add (first) value flag. jump2 already knows how to get rid of no-op moves. */ if (new_src == const0_rtx) - validate_change (insn, &SET_SRC (pat), reg, 0); + { + /* If the constants are different, this is a + truncation, that, if turned into (set (reg) + (reg)), would be discarded. Maybe we should + try a truncMN pattern? */ + if (INTVAL (src) == reg_offset [regno]) + validate_change (insn, &SET_SRC (pat), reg, 0); + } else if (rtx_cost (new_src, PLUS) < rtx_cost (src, SET) && have_add2_insn (reg, new_src)) { @@ -9252,9 +9259,15 @@ reload_cse_move2add (first) int success = 0; if (new_src == const0_rtx) - /* See above why we create (set (reg) (reg)) here. */ - success - = validate_change (next, &SET_SRC (set), reg, 0); + { + if (INTVAL (src) == reg_offset [regno]) + /* See above why we create (set (reg) + (reg)) here. */ + success + = validate_change (next, &SET_SRC (set), reg, 0); + else + success = 0; + } else if ((rtx_cost (new_src, PLUS) < COSTS_N_INSNS (1) + rtx_cost (src3, SET)) && have_add2_insn (reg, new_src)) -- 2.30.2