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| author | Alan Modra <amodra@gmail.com> | 2020-08-30 23:43:54 +0930 |
|---|---|---|
| committer | Alan Modra <amodra@gmail.com> | 2020-08-31 20:28:08 +0930 |
| commit | 737d21903469dca029a791bcd7e84b33c4c3ee16 (patch) | |
| tree | 15682d141c8326475edc27f52dfa7da4ab6d5a1a | |
| parent | e840f2e3e2f5091b392994d47d1f9f31b5d57269 (diff) | |
| download | gdb-737d21903469dca029a791bcd7e84b33c4c3ee16.zip gdb-737d21903469dca029a791bcd7e84b33c4c3ee16.tar.gz gdb-737d21903469dca029a791bcd7e84b33c4c3ee16.tar.bz2 | |
tic4x-coff: ubsan: various shift UB
* config/tc-tic4x.c (tic4x_gen_to_words): Rewrite mantissa
overflow test without UB. Avoid other UB shifts by making them
unsigned.
| -rw-r--r-- | gas/ChangeLog | 6 | ||||
| -rw-r--r-- | gas/config/tc-tic4x.c | 16 |
2 files changed, 12 insertions, 10 deletions
diff --git a/gas/ChangeLog b/gas/ChangeLog index 70e5889..757a311 100644 --- a/gas/ChangeLog +++ b/gas/ChangeLog @@ -1,3 +1,9 @@ +2020-08-30 Alan Modra <amodra@gmail.com> + + * config/tc-tic4x.c (tic4x_gen_to_words): Rewrite mantissa + overflow test without UB. Avoid other UB shifts by making them + unsigned. + 2020-08-31 Cooper Qu <cooper.qu@linux.alibaba.com> * config/tc-csky.c (csky_error_state): New member 'arg_int'. diff --git a/gas/config/tc-tic4x.c b/gas/config/tc-tic4x.c index 1889b47..4efb9d4 100644 --- a/gas/config/tc-tic4x.c +++ b/gas/config/tc-tic4x.c @@ -453,8 +453,8 @@ tic4x_gen_to_words (FLONUM_TYPE flonum, LITTLENUM_TYPE *words, int precision) /* Store the mantissa data into smant and the roundbit into rbit */ for (p = flonum.leader; p >= flonum.low && shift > -16; p--) { - tmp = shift >= 0 ? *p << shift : *p >> -shift; - rbit = shift < 0 ? ((*p >> (-shift-1)) & 0x1) : 0; + tmp = shift >= 0 ? (unsigned) *p << shift : (unsigned) *p >> -shift; + rbit = shift < 0 ? (((unsigned) *p >> (-shift-1)) & 0x1) : 0; smant |= tmp; shift -= 16; } @@ -463,18 +463,14 @@ tic4x_gen_to_words (FLONUM_TYPE flonum, LITTLENUM_TYPE *words, int precision) if(rbit) { /* If the mantissa is going to overflow when added, lets store - the extra bit in mover. -- A special case exists when - mantissa_bits is 31 (E_PRECISION). Then the first test cannot - be trusted, as result is host-dependent, thus the second - test. */ - if( smant == ((unsigned)(1<<(mantissa_bits+1))-1) - || smant == (unsigned)-1 ) /* This is to catch E_PRECISION cases */ + the extra bit in mover. */ + if (smant == (1u << mantissa_bits << 1) - 1) mover=1; smant++; } /* Get the scaled one value */ - sone = (1 << (mantissa_bits)); + sone = 1u << mantissa_bits; /* The number may be unnormalised so renormalise it... */ if(mover) @@ -527,7 +523,7 @@ tic4x_gen_to_words (FLONUM_TYPE flonum, LITTLENUM_TYPE *words, int precision) else { /* Insert the exponent data into the word */ - sfract |= exponent << (mantissa_bits+1); + sfract |= (unsigned) exponent << (mantissa_bits + 1); if (precision == S_PRECISION) words[0] = sfract; |