From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 22737 invoked by alias); 10 Jul 2009 09:45:34 -0000 Received: (qmail 22343 invoked by uid 48); 10 Jul 2009 09:44:44 -0000 Date: Fri, 10 Jul 2009 09:45:00 -0000 Message-ID: <20090710094444.22342.qmail@sourceware.org> X-Bugzilla-Reason: CC References: Subject: [Bug debug/40599] [4.5 regression] GCC error in pre_and_rev_post_order_compute, at cfganal.c:1045 In-Reply-To: Reply-To: gcc-bugzilla@gcc.gnu.org To: gcc-bugs@gcc.gnu.org From: "jakub at gcc dot gnu dot org" Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-bugs-owner@gcc.gnu.org X-SW-Source: 2009-07/txt/msg00855.txt.bz2 ------- Comment #6 from jakub at gcc dot gnu dot org 2009-07-10 09:44 ------- While this triggers only with -fvar-tracking, it is var-tracking related only in that vt_find_locations calls pre_and_rev_post_order_compute. The real problem is that there are 2 basic blocks (in my case 220 and 222) that have no predecessors, so aren't reachable from the entry block and therefore gcc_assert (pre_order_num == n_basic_blocks - NUM_FIXED_BLOCKS); assertion fails (pre_order_num is n_basic_blocks - NUM_FIXED_BLOCKS - 2). In *.split3 we have: (insn 4396 853 4397 204 pkg0017.adb:483 (set (mem/c:SF (plus:DI (reg/f:DI 6 bp) (const_int -1668 [0xfffffffffffff97c])) [0 S4 A32]) (reg:SF 21 xmm0 [orig:143 D.79246 ] [143])) 98 {*movsf_1} (expr_list:REG_DEAD (reg:SF 21 xmm0 [orig:143 D.79246 ] [143]) (nil))) (insn 4397 4396 854 204 pkg0017.adb:483 (set (reg:SF 8 st) (mem/c:SF (plus:DI (reg/f:DI 6 bp) (const_int -1668 [0xfffffffffffff97c])) [0 S4 A32])) 98 {*movsf_1} (nil)) (insn 854 4397 862 204 pkg0017.adb:483 (set (reg:XF 9 st(1) [orig:147 D.79250 ] [147]) (float_extend:XF (reg:SF 8 st))) 137 {*extendsfxf2_i387} (expr_list:REG_DEAD (reg:SF 8 st) (expr_list:REG_EH_REGION (const_int 387 [0x183]) (nil)))) ;; End of basic block 204 -> ( 205 220) ... ;; Start of basic block ( 204) -> 220 ;; bb 220 artificial_defs: { d-1(0){ }d-1(1){ }} ;; bb 220 artificial_uses: { u-1(6){ }u-1(7){ }u-1(16){ }u-1(20){ }} ;; lr in 6 [bp] 7 [sp] 16 [argp] 20 [frame] ;; lr use 6 [bp] 7 [sp] 16 [argp] 20 [frame] ;; lr def 0 [ax] 1 [dx] 42 [r13] ;; Pred edge 204 (ab,eh) (code_label 3492 4766 3497 220 941 "" [0 uses]) but in *.stack: (insn 4396 853 4397 204 pkg0017.adb:483 (set (mem/c:SF (plus:DI (reg/f:DI 6 bp) (const_int -1668 [0xfffffffffffff97c])) [0 S4 A32]) (reg:SF 21 xmm0 [orig:143 D.79246 ] [143])) 98 {*movsf_1} (expr_list:REG_DEAD (reg:SF 21 xmm0 [orig:143 D.79246 ] [143]) (nil))) (insn 4397 4396 862 204 pkg0017.adb:483 (set (reg:SF 8 st) (mem/c:SF (plus:DI (reg/f:DI 6 bp) (const_int -1668 [0xfffffffffffff97c])) [0 S4 A32])) 98 {*movsf_1} (nil)) ;; End of basic block 204 -> ( 205) ... ;; Start of basic block () -> 220 ;; bb 220 artificial_defs: { d-1(0){ }d-1(1){ }} ;; bb 220 artificial_uses: { u-1(6){ }u-1(7){ }u-1(16){ }u-1(20){ }} ;; lr in 6 [bp] 7 [sp] 16 [argp] 20 [frame] ;; lr use 6 [bp] 7 [sp] 16 [argp] 20 [frame] ;; lr def 0 [ax] 1 [dx] 42 [r13] (code_label 3492 4766 3497 220 941 "" [0 uses]) So, either the float_extend is considered throwing when it shouldn't (when would float_extend throw? Only for signalling NaN?), or reg-stack.c is forgetting to cleanup the CFG when it removed insns with REG_EH_REGION. In any case it definitely doesn't look like var-tracking.c's fault. -- http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40599