diff --git a/gcc/ChangeLog b/gcc/ChangeLog index c0461f4629b..bc49772d04f 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +Mon Mar 29 20:52:47 1999 J"orn Rennecke + + * loop.c (maybe_eliminate_biv): For libcalls that set a giv, skip to + end of libcall. + Mon Mar 29 20:35:49 1999 J"orn Rennecke * sh.md (mulsi3): Tag an extra REG_EQUAL note to the middle insn. diff --git a/gcc/loop.c b/gcc/loop.c index 7b6ec8de6e2..a626784a02a 100644 --- a/gcc/loop.c +++ b/gcc/loop.c @@ -8121,6 +8121,26 @@ maybe_eliminate_biv (bl, loop_start, end, eliminate_p, threshold, insn_count) enum rtx_code code = GET_CODE (p); rtx where = threshold >= insn_count ? loop_start : p; + /* If this is a libcall that sets a giv, skip ahead to its end. */ + if (GET_RTX_CLASS (code) == 'i') + { + rtx note = find_reg_note (p, REG_LIBCALL, NULL_RTX); + + if (note) + { + rtx last = XEXP (note, 0); + rtx set = single_set (last); + + if (set && GET_CODE (SET_DEST (set)) == REG) + { + int regno = REGNO (SET_DEST (set)); + + if (REG_IV_TYPE (regno) == GENERAL_INDUCT + && REG_IV_INFO (regno)->src_reg == bl->biv->src_reg) + p = last; + } + } + } if ((code == INSN || code == JUMP_INSN || code == CALL_INSN) && reg_mentioned_p (reg, PATTERN (p)) && ! maybe_eliminate_biv_1 (PATTERN (p), p, bl, eliminate_p, where))