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| author | Jim Blandy <jimb@codesourcery.com> | 2005-12-07 19:30:25 +0000 |
|---|---|---|
| committer | Jim Blandy <jimb@codesourcery.com> | 2005-12-07 19:30:25 +0000 |
| commit | 3d269a592e0d4dc94d69433bfbea85efef4951f4 (patch) | |
| tree | 760932437754dc4928dd8d2e09b102b7c3a6e9a6 /gdb/ax-general.c | |
| parent | f28760375823ffa73dc8db93c6abf9d2e3148981 (diff) | |
| download | gdb-3d269a592e0d4dc94d69433bfbea85efef4951f4.zip gdb-3d269a592e0d4dc94d69433bfbea85efef4951f4.tar.gz gdb-3d269a592e0d4dc94d69433bfbea85efef4951f4.tar.bz2 | |
2005-12-07 Jim Blandy <jimb@redhat.com>
* ax-general.c (ax_reqs): Check stack heights for backward jumps,
too. Correctly check height at target. Doc fixes.
Diffstat (limited to 'gdb/ax-general.c')
| -rw-r--r-- | gdb/ax-general.c | 32 |
1 files changed, 17 insertions, 15 deletions
diff --git a/gdb/ax-general.c b/gdb/ax-general.c index eb7a7ca..52fcfc8 100644 --- a/gdb/ax-general.c +++ b/gdb/ax-general.c @@ -388,15 +388,15 @@ ax_reqs (struct agent_expr *ax, struct agent_reqs *reqs) int reg_mask_len = 1; unsigned char *reg_mask = xmalloc (reg_mask_len * sizeof (reg_mask[0])); - /* Jump target table. targets[i] is non-zero iff there is a jump to - offset i. */ + /* Jump target table. targets[i] is non-zero iff we have found a + jump to offset i. */ char *targets = (char *) alloca (ax->len * sizeof (targets[0])); - /* Instruction boundary table. boundary[i] is non-zero iff an - instruction starts at offset i. */ + /* Instruction boundary table. boundary[i] is non-zero iff our scan + has reached an instruction starting at offset i. */ char *boundary = (char *) alloca (ax->len * sizeof (boundary[0])); - /* Stack height record. iff either targets[i] or boundary[i] is + /* Stack height record. If either targets[i] or boundary[i] is non-zero, heights[i] is the height the stack should have before executing the bytecode at that point. */ int *heights = (int *) alloca (ax->len * sizeof (heights[0])); @@ -437,8 +437,9 @@ ax_reqs (struct agent_expr *ax, struct agent_reqs *reqs) return; } - /* If this instruction is a jump target, does the current stack - height match the stack height at the jump source? */ + /* If this instruction is a forward jump target, does the + current stack height match the stack height at the jump + source? */ if (targets[i] && (heights[i] != height)) { reqs->flaw = agent_flaw_height_mismatch; @@ -472,21 +473,22 @@ ax_reqs (struct agent_expr *ax, struct agent_reqs *reqs) xfree (reg_mask); return; } - /* Have we already found other jumps to the same location? */ - else if (targets[target]) + + /* Do we have any information about what the stack height + should be at the target? */ + if (targets[target] || boundary[target]) { - if (heights[i] != height) + if (heights[target] != height) { reqs->flaw = agent_flaw_height_mismatch; xfree (reg_mask); return; } } - else - { - targets[target] = 1; - heights[target] = height; - } + + /* Record the target, along with the stack height we expect. */ + targets[target] = 1; + heights[target] = height; } /* For unconditional jumps with a successor, check that the |