From d444b5e897369d3e8de7e9e8d93daf75cef2d9a3 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 26 Jun 2003 13:29:55 -0700 Subject: [PATCH] flow.c (propagate_one_insn): Preserve live-at-end registers across tail calls. * flow.c (propagate_one_insn): Preserve live-at-end registers across tail calls. From-SVN: r68544 --- gcc/ChangeLog | 5 +++++ gcc/flow.c | 13 ++++++++++--- 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 735494437d4..274e7a531ab 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2003-06-26 Richard Henderson + + * flow.c (propagate_one_insn): Preserve live-at-end registers + across tail calls. + 2003-06-26 J"orn Rennecke * reload.c (can_reload_into): New function. diff --git a/gcc/flow.c b/gcc/flow.c index b08a6e8e331..58859405aab 100644 --- a/gcc/flow.c +++ b/gcc/flow.c @@ -1770,8 +1770,10 @@ propagate_one_insn (pbi, insn) if (GET_CODE (insn) == CALL_INSN) { - int i; + regset live_at_end; + bool sibcall_p; rtx note, cond; + int i; cond = NULL_RTX; if (GET_CODE (PATTERN (insn)) == COND_EXEC) @@ -1796,9 +1798,14 @@ propagate_one_insn (pbi, insn) mark_set_1 (pbi, CLOBBER, XEXP (XEXP (note, 0), 0), cond, insn, pbi->flags); - /* Calls change all call-used and global registers. */ + /* Calls change all call-used and global registers; sibcalls do not + clobber anything that must be preserved at end-of-function. */ + + sibcall_p = SIBLING_CALL_P (insn); + live_at_end = EXIT_BLOCK_PTR->global_live_at_start; for (i = 0; i < FIRST_PSEUDO_REGISTER; i++) - if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i)) + if (TEST_HARD_REG_BIT (regs_invalidated_by_call, i) + && ! (sibcall_p && REGNO_REG_SET_P (live_at_end, i))) { /* We do not want REG_UNUSED notes for these registers. */ mark_set_1 (pbi, CLOBBER, regno_reg_rtx[i], cond, insn, -- 2.30.2