From 78ee8381bf0ebd09a92936bdb9e1b5c9fc85ad88 Mon Sep 17 00:00:00 2001 From: Jakub Jelinek Date: Tue, 28 Dec 2021 17:39:23 +0100 Subject: [PATCH] optabs: Fix up checking for CALLs in newly added code by double-word divmod [PR103838] These two spots are meant to punt if the newly added code contains any CALL_INSNs, because in that case having a large sequence of insns that also calls something is undesirable, better have one call that is optimized in itself well. The functions do last = get_last_insn (); before emitting any insns (and expand_binop as the ultimate caller uses delete_insns_since if the expansion fails), but the checks were incorrect for 2 reasons: 1) it checked not just what follows after that last insn, but also the last insn itself; so, if the division or modulo is immediately preceded by a CALL_INSN, then we punt; this also causes -fcompare-debug failures if the CALL_INSN is with -g followed by one or more DEBUG_INSNs 2) if get_last_insn () is NULL (i.e. emitting into a new sequence), then we didn't check anything 2021-12-28 Jakub Jelinek PR debug/103838 * optabs.c (expand_doubleword_mod, expand_doubleword_divmod): Only check newly added insns for CALL_P, not the last insn of previous code. * gcc.dg/pr103838.c: New test. --- gcc/optabs.c | 8 ++++++++ gcc/testsuite/gcc.dg/pr103838.c | 28 ++++++++++++++++++++++++++++ 2 files changed, 36 insertions(+) create mode 100644 gcc/testsuite/gcc.dg/pr103838.c diff --git a/gcc/optabs.c b/gcc/optabs.c index 019bbb6..ca00bbd 100644 --- a/gcc/optabs.c +++ b/gcc/optabs.c @@ -1135,6 +1135,10 @@ expand_doubleword_mod (machine_mode mode, rtx op0, rtx op1, bool unsignedp) remainder = convert_modes (mode, word_mode, remainder, unsignedp); /* Punt if we need any library calls. */ + if (last) + last = NEXT_INSN (last); + else + last = get_insns (); for (; last; last = NEXT_INSN (last)) if (CALL_P (last)) return NULL_RTX; @@ -1228,6 +1232,10 @@ expand_doubleword_divmod (machine_mode mode, rtx op0, rtx op1, rtx *rem, } /* Punt if we need any library calls. */ + if (last) + last = NEXT_INSN (last); + else + last = get_insns (); for (; last; last = NEXT_INSN (last)) if (CALL_P (last)) return NULL_RTX; diff --git a/gcc/testsuite/gcc.dg/pr103838.c b/gcc/testsuite/gcc.dg/pr103838.c new file mode 100644 index 0000000..cde44e6 --- /dev/null +++ b/gcc/testsuite/gcc.dg/pr103838.c @@ -0,0 +1,28 @@ +/* PR debug/103838 */ +/* { dg-do compile } */ +/* { dg-options "-O2 -fcompare-debug" } */ + +#ifdef __SIZEOF_INT128__ +__int128 m; +#else +long long m; +#endif +int n; + +__attribute__((noinline)) void +bar (void) +{ + n += !!m; +} + +void +foo (void) +{ + int i; + + for (i = 0; i < 2; ++i) + { + bar (); + m /= 3; + } +} -- 2.7.4