diff options
Diffstat (limited to 'gcc/tree-ssa-strlen.c')
| -rw-r--r-- | gcc/tree-ssa-strlen.c | 75 |
1 files changed, 47 insertions, 28 deletions
diff --git a/gcc/tree-ssa-strlen.c b/gcc/tree-ssa-strlen.c index 94ed2bedc03..71ed0ff1b45 100644 --- a/gcc/tree-ssa-strlen.c +++ b/gcc/tree-ssa-strlen.c @@ -44,6 +44,7 @@ along with GCC; see the file COPYING3. If not see #include "domwalk.h" #include "tree-ssa-alias.h" #include "tree-ssa-propagate.h" +#include "tree-ssa-strlen.h" #include "params.h" #include "ipa-chkp.h" #include "tree-hash-traits.h" @@ -1780,11 +1781,12 @@ is_strlen_related_p (tree src, tree len) return false; } -/* A helper of handle_builtin_stxncpy. Check to see if the specified - bound is a) equal to the size of the destination DST and if so, b) - if it's immediately followed by DST[CNT - 1] = '\0'. If a) holds - and b) does not, warn. Otherwise, do nothing. Return true if - diagnostic has been issued. +/* Called by handle_builtin_stxncpy and by gimple_fold_builtin_strncpy + in gimple-fold.c. + Check to see if the specified bound is a) equal to the size of + the destination DST and if so, b) if it's immediately followed by + DST[CNT - 1] = '\0'. If a) holds and b) does not, warn. Otherwise, + do nothing. Return true if diagnostic has been issued. The purpose is to diagnose calls to strncpy and stpncpy that do not nul-terminate the copy while allowing for the idiom where @@ -1795,7 +1797,7 @@ is_strlen_related_p (tree src, tree len) a[sizeof a - 1] = '\0'; */ -static bool +bool maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) { gimple *stmt = gsi_stmt (gsi); @@ -1831,8 +1833,11 @@ maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) return false; /* Negative value is the constant string length. If it's less than - the lower bound there is no truncation. */ - int sidx = get_stridx (src); + the lower bound there is no truncation. Avoid calling get_stridx() + when ssa_ver_to_stridx is empty. That implies the caller isn't + running under the control of this pass and ssa_ver_to_stridx hasn't + been created yet. */ + int sidx = ssa_ver_to_stridx.length () ? get_stridx (src) : 0; if (sidx < 0 && wi::gtu_p (cntrange[0], ~sidx)) return false; @@ -1878,6 +1883,7 @@ maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) poly_int64 lhsoff; tree lhsbase = get_addr_base_and_unit_offset (lhs, &lhsoff); if (lhsbase + && dstbase && known_eq (dstoff, lhsoff) && operand_equal_p (dstbase, lhsbase, 0)) return false; @@ -1934,23 +1940,35 @@ maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) lenrange[0] = wi::shwi (0, prec); } - if (wi::geu_p (lenrange[0], cntrange[1])) + gcall *call = as_a <gcall *> (stmt); + + if (lenrange[0] == cntrange[1] && cntrange[0] == cntrange[1]) + return warning_at (callloc, OPT_Wstringop_truncation, + (integer_onep (cnt) + ? G_("%G%qD output truncated before terminating " + "nul copying %E byte from a string of the " + "same length") + : G_("%G%qD output truncated before terminating nul " + "copying %E bytes from a string of the same " + "length")), + call, func, cnt); + else if (wi::geu_p (lenrange[0], cntrange[1])) { /* The shortest string is longer than the upper bound of the count so the truncation is certain. */ if (cntrange[0] == cntrange[1]) return warning_at (callloc, OPT_Wstringop_truncation, integer_onep (cnt) - ? G_("%qD output truncated copying %E byte " + ? G_("%G%qD output truncated copying %E byte " "from a string of length %wu") - : G_("%qD output truncated copying %E bytes " + : G_("%G%qD output truncated copying %E bytes " "from a string of length %wu"), - func, cnt, lenrange[0].to_uhwi ()); + call, func, cnt, lenrange[0].to_uhwi ()); return warning_at (callloc, OPT_Wstringop_truncation, - "%qD output truncated copying between %wu " + "%G%qD output truncated copying between %wu " "and %wu bytes from a string of length %wu", - func, cntrange[0].to_uhwi (), + call, func, cntrange[0].to_uhwi (), cntrange[1].to_uhwi (), lenrange[0].to_uhwi ()); } else if (wi::geu_p (lenrange[1], cntrange[1])) @@ -1960,16 +1978,16 @@ maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) if (cntrange[0] == cntrange[1]) return warning_at (callloc, OPT_Wstringop_truncation, integer_onep (cnt) - ? G_("%qD output may be truncated copying %E " + ? G_("%G%qD output may be truncated copying %E " "byte from a string of length %wu") - : G_("%qD output may be truncated copying %E " + : G_("%G%qD output may be truncated copying %E " "bytes from a string of length %wu"), - func, cnt, lenrange[1].to_uhwi ()); + call, func, cnt, lenrange[1].to_uhwi ()); return warning_at (callloc, OPT_Wstringop_truncation, - "%qD output may be truncated copying between %wu " + "%G%qD output may be truncated copying between %wu " "and %wu bytes from a string of length %wu", - func, cntrange[0].to_uhwi (), + call, func, cntrange[0].to_uhwi (), cntrange[1].to_uhwi (), lenrange[1].to_uhwi ()); } @@ -1981,9 +1999,9 @@ maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) the lower bound of the specified count but shorter than the upper bound the copy may (but need not) be truncated. */ return warning_at (callloc, OPT_Wstringop_truncation, - "%qD output may be truncated copying between %wu " - "and %wu bytes from a string of length %wu", - func, cntrange[0].to_uhwi (), + "%G%qD output may be truncated copying between " + "%wu and %wu bytes from a string of length %wu", + call, func, cntrange[0].to_uhwi (), cntrange[1].to_uhwi (), lenrange[0].to_uhwi ()); } } @@ -2002,8 +2020,8 @@ maybe_diag_stxncpy_trunc (gimple_stmt_iterator gsi, tree src, tree cnt) if (cntrange[0] == cntrange[1]) return warning_at (callloc, OPT_Wstringop_truncation, - "%qD specified bound %E equals destination size", - func, cnt); + "%G%qD specified bound %E equals destination size", + as_a <gcall *> (stmt), func, cnt); } return false; @@ -2102,14 +2120,15 @@ handle_builtin_stxncpy (built_in_function, gimple_stmt_iterator *gsi) if (sisrc == silen && is_strlen_related_p (src, len) && warning_at (callloc, OPT_Wstringop_truncation, - "%qD output truncated before terminating nul " + "%G%qD output truncated before terminating nul " "copying as many bytes from a string as its length", - func)) + as_a <gcall *>(stmt), func)) warned = true; else if (silen && is_strlen_related_p (src, silen->ptr)) warned = warning_at (callloc, OPT_Wstringop_overflow_, - "%qD specified bound depends on the length " - "of the source argument", func); + "%G%qD specified bound depends on the length " + "of the source argument", + as_a <gcall *>(stmt), func); if (warned) { location_t strlenloc = pss->second; |