diff options
Diffstat (limited to 'gcc/cse.c')
| -rw-r--r-- | gcc/cse.c | 32 |
1 files changed, 27 insertions, 5 deletions
@@ -7488,7 +7488,7 @@ count_reg_usage (x, counts, dest, incr) static bool set_live_p (set, insn, counts) rtx set; - rtx insn; + rtx insn ATTRIBUTE_UNUSED; int *counts; { #ifdef HAVE_cc0 @@ -7630,8 +7630,19 @@ delete_trivially_dead_insns (insns, nreg, preserve_basic_blocks) if (find_reg_note (insn, REG_RETVAL, NULL_RTX)) { in_libcall = 1; - live_insn = 1; - dead_libcall = dead_libcall_p (insn); + /* If the insn storing return value is dead, whole libcall is dead. + Otherwise attempt to eliminate libcall by doing an direct + operation. */ + if (!insn_live_p (insn, counts)) + { + live_insn = 0; + dead_libcall = 1; + } + else + { + live_insn = 1; + dead_libcall = dead_libcall_p (insn); + } } else if (in_libcall) live_insn = ! dead_libcall; @@ -7671,8 +7682,19 @@ delete_trivially_dead_insns (insns, nreg, preserve_basic_blocks) if (find_reg_note (insn, REG_RETVAL, NULL_RTX)) { in_libcall = 1; - live_insn = 1; - dead_libcall = dead_libcall_p (insn); + /* If the insn storing return value is dead, whole libcall is dead. + Otherwise attempt to eliminate libcall by doing an direct + operation. */ + if (!insn_live_p (insn, counts)) + { + live_insn = 0; + dead_libcall = 1; + } + else + { + live_insn = 1; + dead_libcall = dead_libcall_p (insn); + } } else if (in_libcall) live_insn = ! dead_libcall; |