From 99af0d26bd5e46ec40030ff2d3c68029d7129aa9 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Thu, 26 Jun 2003 13:45:18 -0700 Subject: [PATCH] flow.c (propagate_one_insn): Kill function return value registers across tail calls. * flow.c (propagate_one_insn): Kill function return value registers across tail calls. From-SVN: r68546 --- gcc/ChangeLog | 3 +++ gcc/flow.c | 7 +++++-- 2 files changed, 8 insertions(+), 2 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 274e7a531ab..31b98151711 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,8 @@ 2003-06-26 Richard Henderson + * flow.c (propagate_one_insn): Kill function return value + registers across tail calls. + * flow.c (propagate_one_insn): Preserve live-at-end registers across tail calls. diff --git a/gcc/flow.c b/gcc/flow.c index 58859405aab..e51d477c94f 100644 --- a/gcc/flow.c +++ b/gcc/flow.c @@ -1799,13 +1799,16 @@ propagate_one_insn (pbi, insn) cond, insn, pbi->flags); /* Calls change all call-used and global registers; sibcalls do not - clobber anything that must be preserved at end-of-function. */ + clobber anything that must be preserved at end-of-function, + except for return values. */ 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) - && ! (sibcall_p && REGNO_REG_SET_P (live_at_end, i))) + && ! (sibcall_p + && REGNO_REG_SET_P (live_at_end, i) + && !FUNCTION_VALUE_REGNO_P (i))) { /* We do not want REG_UNUSED notes for these registers. */ mark_set_1 (pbi, CLOBBER, regno_reg_rtx[i], cond, insn,