From d8e5fff6b74b82c2ac3254be9a1f0fb6b30dbdbf Mon Sep 17 00:00:00 2001 From: "Vladimir N. Makarov" Date: Thu, 10 Mar 2022 16:16:00 -0500 Subject: [PATCH] [PR103074] LRA: Check new conflicts when splitting hard reg live range. Splitting hard register live range can create (artificial) conflict of the hard register with another pseudo because of simplified conflict calculation in LRA. We should check such conflict on the next assignment sub-pass and spill and reassign the pseudo if necessary. The patch implements this. gcc/ChangeLog: PR target/103074 * lra-constraints.cc (split_reg): Set up check_and_force_assignment_correctness_p when splitting hard register live range. gcc/testsuite/ChangeLog: PR target/103074 * gcc.target/i386/pr103074.c: New. --- gcc/lra-constraints.cc | 9 +++++++-- gcc/testsuite/gcc.target/i386/pr103074.c | 16 ++++++++++++++++ 2 files changed, 23 insertions(+), 2 deletions(-) create mode 100644 gcc/testsuite/gcc.target/i386/pr103074.c diff --git a/gcc/lra-constraints.cc b/gcc/lra-constraints.cc index 080b44ad87ab..d92ab76908c8 100644 --- a/gcc/lra-constraints.cc +++ b/gcc/lra-constraints.cc @@ -5994,12 +5994,17 @@ split_reg (bool before_p, int original_regno, rtx_insn *insn, before_p ? NULL : save, call_save_p ? "Add save<-reg" : "Add split<-reg"); - if (nregs > 1) + if (nregs > 1 || original_regno < FIRST_PSEUDO_REGISTER) /* If we are trying to split multi-register. We should check conflicts on the next assignment sub-pass. IRA can allocate on sub-register levels, LRA do this on pseudos level right now and this discrepancy may create allocation conflicts after - splitting. */ + splitting. + + If we are trying to split hard register we should also check conflicts + as such splitting can create artificial conflict of the hard register + with another pseudo because of simplified conflict calculation in + LRA. */ check_and_force_assignment_correctness_p = true; if (lra_dump_file != NULL) fprintf (lra_dump_file, diff --git a/gcc/testsuite/gcc.target/i386/pr103074.c b/gcc/testsuite/gcc.target/i386/pr103074.c new file mode 100644 index 000000000000..276ad82a1de1 --- /dev/null +++ b/gcc/testsuite/gcc.target/i386/pr103074.c @@ -0,0 +1,16 @@ +/* { dg-do compile } */ +/* { dg-options "-march=bonnell -Os -fPIC -fschedule-insns -w" } */ + +void +serialize_collection (char *ptr, int a, int need_owner) +{ + if (need_owner) + __builtin_sprintf(ptr, "%d:%d", 0, a); + else + { + static char buff[32]; + + __builtin_sprintf(buff, "%d:%d", a >> 32, a); + __builtin_sprintf(ptr, "%d:%d:\"%s\"", 0, 0, buff); + } +} -- 2.47.2