public inbox for gdb-testers@sourceware.org
help / color / mirror / Atom feed
* [binutils-gdb] ubsan: bfin: shift exponent is too large
@ 2019-12-11  6:54 gdb-buildbot
  2019-12-11  6:38 ` Failures on Ubuntu-Aarch64-native-extended-gdbserver-m64, branch master gdb-buildbot
                   ` (7 more replies)
  0 siblings, 8 replies; 9+ messages in thread
From: gdb-buildbot @ 2019-12-11  6:54 UTC (permalink / raw)
  To: gdb-testers

*** TEST RESULTS FOR COMMIT 2fd2b153a3819d3ab6b9c4cf06943d498187714c ***

commit 2fd2b153a3819d3ab6b9c4cf06943d498187714c
Author:     Alan Modra <amodra@gmail.com>
AuthorDate: Tue Dec 10 22:32:06 2019 +1030
Commit:     Alan Modra <amodra@gmail.com>
CommitDate: Wed Dec 11 11:37:44 2019 +1030

    ubsan: bfin: shift exponent is too large
    
    This was the following in fmtconst_val, x is unsigned int.
        x = SIGNEXTEND (x, constant_formats[cf].nbits);
    Problem is, the SIGNEXTEND macro assumed its arg was a long and sign
    extended by shifting left then shifting right, and didn't cast the
    arg.  So don't do the silly shift thing.  It's not guaranteed to work
    anyway according to the C standard.  ">>" might do a logical shift
    even if its args are signed.
    
            * bfin-dis.c (HOST_LONG_WORD_SIZE, XFIELD): Delete.
            (SIGNBIT): New.
            (MASKBITS, SIGNEXTEND): Rewrite.
            (fmtconst): Don't use ? expression now that SIGNEXTEND uses
            unsigned arithmetic, instead assign result of SIGNEXTEND back
            to x.
            (fmtconst_val): Use 1u in shift expression.

diff --git a/opcodes/ChangeLog b/opcodes/ChangeLog
index d3f1e69940..faa160a37b 100644
--- a/opcodes/ChangeLog
+++ b/opcodes/ChangeLog
@@ -1,3 +1,13 @@
+2019-12-11  Alan Modra  <amodra@gmail.com>
+
+	* bfin-dis.c (HOST_LONG_WORD_SIZE, XFIELD): Delete.
+	(SIGNBIT): New.
+	(MASKBITS, SIGNEXTEND): Rewrite.
+	(fmtconst): Don't use ? expression now that SIGNEXTEND uses
+	unsigned arithmetic, instead assign result of SIGNEXTEND back
+	to x.
+	(fmtconst_val): Use 1u in shift expression.
+
 2019-12-11  Alan Modra  <amodra@gmail.com>
 
 	* arc-dis.c (find_format_from_table): Use ull constant when
diff --git a/opcodes/bfin-dis.c b/opcodes/bfin-dis.c
index 811509fa1a..711f7e1e07 100644
--- a/opcodes/bfin-dis.c
+++ b/opcodes/bfin-dis.c
@@ -33,10 +33,9 @@
 
 typedef long TIword;
 
-#define HOST_LONG_WORD_SIZE (sizeof (long) * 8)
-#define XFIELD(w,p,s)       (((w) & ((1 << (s)) - 1) << (p)) >> (p))
-#define SIGNEXTEND(v, n)    ((v << (HOST_LONG_WORD_SIZE - (n))) >> (HOST_LONG_WORD_SIZE - (n)))
-#define MASKBITS(val, bits) (val & ((1 << bits) - 1))
+#define SIGNBIT(bits)       (1ul << ((bits) - 1))
+#define MASKBITS(val, bits) ((val) & ((1ul << (bits)) - 1))
+#define SIGNEXTEND(v, n)    ((MASKBITS (v, n) ^ SIGNBIT (n)) - SIGNBIT (n))
 
 #include "disassemble.h"
 
@@ -125,8 +124,11 @@ fmtconst (const_forms_t cf, TIword x, bfd_vma pc, disassemble_info *outf)
 
   if (constant_formats[cf].reloc)
     {
-      bfd_vma ea = (((constant_formats[cf].pcrel ? SIGNEXTEND (x, constant_formats[cf].nbits)
-		      : x) + constant_formats[cf].offset) << constant_formats[cf].scale);
+      bfd_vma ea;
+
+      if (constant_formats[cf].pcrel)
+	x = SIGNEXTEND (x, constant_formats[cf].nbits);
+      ea = (x + constant_formats[cf].offset) << constant_formats[cf].scale;
       if (constant_formats[cf].pcrel)
 	ea += pc;
 
@@ -153,8 +155,8 @@ fmtconst (const_forms_t cf, TIword x, bfd_vma pc, disassemble_info *outf)
       x = x | (1 << constant_formats[cf].nbits);
       x = SIGNEXTEND (x, nb);
     }
-  else
-    x = constant_formats[cf].issigned ? SIGNEXTEND (x, constant_formats[cf].nbits) : x;
+  else if (constant_formats[cf].issigned)
+    x = SIGNEXTEND (x, constant_formats[cf].nbits);
 
   if (constant_formats[cf].offset)
     x += constant_formats[cf].offset;
@@ -180,10 +182,11 @@ fmtconst_val (const_forms_t cf, unsigned int x, unsigned int pc)
 {
   if (0 && constant_formats[cf].reloc)
     {
-      bu32 ea = (((constant_formats[cf].pcrel
-		   ? SIGNEXTEND (x, constant_formats[cf].nbits)
-		   : x) + constant_formats[cf].offset)
-		 << constant_formats[cf].scale);
+      bu32 ea;
+
+      if (constant_formats[cf].pcrel)
+	x = SIGNEXTEND (x, constant_formats[cf].nbits);
+      ea = (x + constant_formats[cf].offset) << constant_formats[cf].scale;
       if (constant_formats[cf].pcrel)
 	ea += pc;
 
@@ -194,7 +197,7 @@ fmtconst_val (const_forms_t cf, unsigned int x, unsigned int pc)
   if (constant_formats[cf].negative)
     {
       int nb = constant_formats[cf].nbits + 1;
-      x = x | (1 << constant_formats[cf].nbits);
+      x = x | (1u << constant_formats[cf].nbits);
       x = SIGNEXTEND (x, nb);
     }
   else if (constant_formats[cf].issigned)


^ permalink raw reply	[flat|nested] 9+ messages in thread
end of thread, other threads:[~2019-12-11 12:44 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-12-11  6:54 [binutils-gdb] ubsan: bfin: shift exponent is too large gdb-buildbot
2019-12-11  6:38 ` Failures on Ubuntu-Aarch64-native-extended-gdbserver-m64, branch master gdb-buildbot
2019-12-11  6:55 ` Failures on Ubuntu-Aarch64-native-gdbserver-m64, " gdb-buildbot
2019-12-11 11:50 ` Failures on Fedora-x86_64-m64, " gdb-buildbot
2019-12-11 11:58 ` Failures on Fedora-x86_64-m32, " gdb-buildbot
2019-12-11 12:33 ` Failures on Fedora-x86_64-native-extended-gdbserver-m32, " gdb-buildbot
2019-12-11 12:38 ` Failures on Fedora-x86_64-native-extended-gdbserver-m64, " gdb-buildbot
2019-12-11 12:44 ` Failures on Fedora-x86_64-native-gdbserver-m32, " gdb-buildbot
2019-12-11 12:45 ` Failures on Fedora-x86_64-native-gdbserver-m64, " gdb-buildbot

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).