diff options
| -rw-r--r-- | gas/ginsn.c | 101 | ||||
| -rw-r--r-- | gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.d | 43 | ||||
| -rw-r--r-- | gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.l | 2 | ||||
| -rw-r--r-- | gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.s | 42 | ||||
| -rw-r--r-- | gas/testsuite/gas/scfi/x86_64/scfi-x86-64.exp | 2 |
5 files changed, 164 insertions, 26 deletions
diff --git a/gas/ginsn.c b/gas/ginsn.c index 492e161..be06324 100644 --- a/gas/ginsn.c +++ b/gas/ginsn.c @@ -614,6 +614,8 @@ gbb_cleanup (gbbS **bbp) *bbp = NULL; } +/* Add an edge from the source bb FROM_BB to the sink bb TO_BB. */ + static void bb_add_edge (gbbS* from_bb, gbbS *to_bb) { @@ -638,7 +640,7 @@ bb_add_edge (gbbS* from_bb, gbbS *to_bb) } else { - /* Get the tail of the list. */ + /* Get the head of the list. */ tmpedge = from_bb->out_gedges; while (tmpedge) { @@ -689,6 +691,9 @@ static gbbS * add_bb_at_ginsn (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, int *errp); +/* Return the already existing basic block (if present), which begins with + GINSN, in the given GCFG. Return NULL otherwise. */ + static gbbS * find_bb (gcfgS *gcfg, ginsnS *ginsn) { @@ -708,13 +713,18 @@ find_bb (gcfgS *gcfg, ginsnS *ginsn) break; } } - /* Must be found if ginsn is visited. */ + /* Must be found because ginsn is visited. */ gas_assert (found_bb); } return found_bb; } +/* Get the basic block starting at GINSN in the GCFG. + + If not already present, the function will make one, while adding an edge + from the PREV_BB to it. */ + static gbbS * find_or_make_bb (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, int *errp) @@ -722,26 +732,40 @@ find_or_make_bb (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, gbbS *found_bb = NULL; found_bb = find_bb (gcfg, ginsn); - if (found_bb) - return found_bb; + if (!found_bb) + found_bb = add_bb_at_ginsn (func, gcfg, ginsn, prev_bb, errp); + + gas_assert (found_bb); + gas_assert (found_bb->first_ginsn == ginsn); - return add_bb_at_ginsn (func, gcfg, ginsn, prev_bb, errp); + return found_bb; } -/* Add the basic block starting at GINSN to the given GCFG. - Also adds an edge from the PREV_BB to the newly added basic block. +/* Add basic block(s) for all reachable, unvisited ginsns, starting from GINSN, + to the given GCFG. Also add an edge from the PREV_BB to the root of the + newly added basic block(s). - This is a recursive function which returns the root of the added - basic blocks. */ + This is a recursive function which returns the root of the added basic + blocks. */ static gbbS * add_bb_at_ginsn (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, int *errp) { + gbbS *root_bb = NULL; gbbS *current_bb = NULL; ginsnS *target_ginsn = NULL; const symbolS *taken_label; + /* Create a new bb. N.B. The caller must ensure bb with this ginsn does not + already exist. */ + gas_assert (!find_bb (gcfg, ginsn)); + root_bb = XCNEW (gbbS); + cfg_add_bb (gcfg, root_bb); + root_bb->first_ginsn = ginsn; + + current_bb = root_bb; + while (ginsn) { /* Skip these as they may be right after a GINSN_TYPE_RETURN. @@ -749,6 +773,8 @@ add_bb_at_ginsn (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, end of bb, and a logical exit from function. */ if (GINSN_F_FUNC_END_P (ginsn)) { + /* Dont mark them visited yet though, leaving the option of these + being visited via other control flows as applicable. */ ginsn = ginsn->next; continue; } @@ -765,27 +791,27 @@ add_bb_at_ginsn (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, bb_add_edge (prev_bb, current_bb); break; } - else if (current_bb && GINSN_F_USER_LABEL_P (ginsn)) + else if (current_bb && current_bb->first_ginsn != ginsn + && GINSN_F_USER_LABEL_P (ginsn)) { - /* Create new bb starting at this label ginsn. */ + /* Create new bb starting at ginsn for (user-defined) label. This is + likely going to be a destination of a some control flow. */ prev_bb = current_bb; - find_or_make_bb (func, gcfg, ginsn, prev_bb, errp); + current_bb = find_or_make_bb (func, gcfg, ginsn, prev_bb, errp); + bb_add_edge (prev_bb, current_bb); break; } if (current_bb == NULL) { - /* Create a new bb. */ current_bb = XCNEW (gbbS); cfg_add_bb (gcfg, current_bb); + current_bb->first_ginsn = ginsn; /* Add edge for the Not Taken, or Fall-through path. */ if (prev_bb) bb_add_edge (prev_bb, current_bb); } - if (current_bb->first_ginsn == NULL) - current_bb->first_ginsn = ginsn; - ginsn->visited = true; current_bb->num_ginsns++; current_bb->last_ginsn = ginsn; @@ -809,16 +835,21 @@ add_bb_at_ginsn (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, taken_label = ginsn->src[0].sym; gas_assert (taken_label); - /* Preserve the prev_bb to be the dominator bb as we are - going to follow the taken path of the conditional branch - soon. */ + /* Preserve the prev_bb to be the source bb as we are going to + follow the taken path of the conditional branch soon. */ prev_bb = current_bb; /* Follow the target on the taken path. */ target_ginsn = label_ginsn_map_find (taken_label); /* Add the bb for the target of the taken branch. */ if (target_ginsn) - find_or_make_bb (func, gcfg, target_ginsn, prev_bb, errp); + { + current_bb = find_or_make_bb (func, gcfg, target_ginsn, + prev_bb, errp); + gas_assert (prev_bb); + bb_add_edge (prev_bb, current_bb); + current_bb = NULL; + } else { *errp = GCFG_JLABEL_NOT_PRESENT; @@ -826,27 +857,45 @@ add_bb_at_ginsn (const symbolS *func, gcfgS *gcfg, ginsnS *ginsn, gbbS *prev_bb, _("missing label '%s' in func '%s' may result in imprecise cfg"), S_GET_NAME (taken_label), S_GET_NAME (func)); } - /* Add the bb for the fall through path. */ - find_or_make_bb (func, gcfg, ginsn->next, prev_bb, errp); + + if (ginsn->type == GINSN_TYPE_JUMP_COND) + { + /* Add the bb for the fall through path. */ + current_bb = find_or_make_bb (func, gcfg, ginsn->next, + prev_bb, errp); + gas_assert (prev_bb); + bb_add_edge (prev_bb, current_bb); + current_bb = NULL; + } + else + { + /* Unconditional jump. Current BB has been processed. */ + current_bb = NULL; + /* We'll come back to the ginsns following these (local) + unconditional jmps from another path if they are indeed + reachable code. */ + break; + } } else { gas_assert (ginsn->type == GINSN_TYPE_RETURN || (ginsn->type == GINSN_TYPE_JUMP && !ginsn_direct_local_jump_p (ginsn))); + /* Current BB has been processed. */ + current_bb = NULL; + /* We'll come back to the ginsns following GINSN_TYPE_RETURN or other (non-local) unconditional jmps from another path if they are indeed reachable code. */ break; } - - /* Current BB has been processed. */ - current_bb = NULL; } + ginsn = ginsn->next; } - return current_bb; + return root_bb; } static int diff --git a/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.d b/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.d new file mode 100644 index 0000000..841fc3c --- /dev/null +++ b/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.d @@ -0,0 +1,43 @@ +#as: --scfi=experimental -W +#as: +#objdump: -Wf +#name: Synthesize CFI in presence of control flow 4 +#... +Contents of the .eh_frame section: + +00000000 0+0014 0+0000 CIE + Version: 1 + Augmentation: "zR" + Code alignment factor: 1 + Data alignment factor: -8 + Return address column: 16 + Augmentation data: 1b + DW_CFA_def_cfa: r7 \(rsp\) ofs 8 + DW_CFA_offset: r16 \(rip\) at cfa-8 + DW_CFA_nop + DW_CFA_nop + +0+0018 0+002c 0+001c FDE cie=00000000 pc=0000000000000000..0000000000000045 + DW_CFA_advance_loc: 1 to 0000000000000001 + DW_CFA_def_cfa_offset: 16 + DW_CFA_offset: r3 \(rbx\) at cfa-16 + DW_CFA_advance_loc: 6 to 0000000000000007 + DW_CFA_def_cfa_offset: 32 + DW_CFA_advance_loc: 15 to 0000000000000016 + DW_CFA_remember_state + DW_CFA_advance_loc: 4 to 000000000000001a + DW_CFA_def_cfa_offset: 16 + DW_CFA_advance_loc: 1 to 000000000000001b + DW_CFA_restore: r3 \(rbx\) + DW_CFA_def_cfa_offset: 8 + DW_CFA_advance_loc: 1 to 000000000000001c + DW_CFA_restore_state + DW_CFA_advance_loc: 35 to 000000000000003f + DW_CFA_def_cfa_offset: 16 + DW_CFA_advance_loc: 1 to 0000000000000040 + DW_CFA_restore: r3 \(rbx\) + DW_CFA_def_cfa_offset: 8 + DW_CFA_nop +#... + +#pass diff --git a/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.l b/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.l new file mode 100644 index 0000000..abca835 --- /dev/null +++ b/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.l @@ -0,0 +1,2 @@ +.*Assembler messages: +.*5: Warning: SCFI ignores most user-specified CFI directives diff --git a/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.s b/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.s new file mode 100644 index 0000000..ebcc6ad --- /dev/null +++ b/gas/testsuite/gas/scfi/x86_64/scfi-cfg-4.s @@ -0,0 +1,42 @@ + .text + .globl foo_handler + .type foo_handler, @function +foo_handler: + .cfi_startproc + pushq %rbx + .cfi_def_cfa_offset 16 + .cfi_offset %rbx, -16 + movl %esi, %ebx + subq $16, %rsp + .cfi_def_cfa_offset 32 + movl current_style(%rip), %eax + cmpl $-1, %eax + je .L12 + testb $4, %al + jne .L13 +.L1: + .cfi_remember_state + addq $16, %rsp + .cfi_def_cfa_offset 16 + popq %rbx + .cfi_restore %rbx + .cfi_def_cfa_offset 8 + ret +.L13: + .cfi_restore_state + movq %rdi, 8(%rsp) + call foo_handler_v2 + testq %rax, %rax + jne .L1 + movl current_style(%rip), %eax + movq 8(%rsp), %rdi + jmp .L3 +.L12: + addq $16, %rsp + .cfi_def_cfa_offset 16 + popq %rbx + .cfi_restore %rbx + .cfi_def_cfa_offset 8 + jmp xstrdup + .cfi_endproc + .size foo_handler, .-foo_handler diff --git a/gas/testsuite/gas/scfi/x86_64/scfi-x86-64.exp b/gas/testsuite/gas/scfi/x86_64/scfi-x86-64.exp index c004d99..63f0d7e 100644 --- a/gas/testsuite/gas/scfi/x86_64/scfi-x86-64.exp +++ b/gas/testsuite/gas/scfi/x86_64/scfi-x86-64.exp @@ -80,6 +80,8 @@ if { ([istarget "x86_64-*-*"] && ![istarget "x86_64-*-linux*-gnux32"]) } then { run_list_test "scfi-cfg-2" "--scfi=experimental --warn" run_dump_test "scfi-cfg-3" run_list_test "scfi-cfg-3" "--scfi=experimental --warn" + run_dump_test "scfi-cfg-4" + run_list_test "scfi-cfg-4" "--scfi=experimental --warn" run_dump_test "scfi-asm-marker-1" run_list_test "scfi-asm-marker-1" "--scfi=experimental --warn" run_dump_test "scfi-asm-marker-2" |