[binutils-gdb] kvx: ubsan: integer overflow

[Alan Modra]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=990f9a1d13e3e6fa9443d23fdd146528d4f21159

commit 990f9a1d13e3e6fa9443d23fdd146528d4f21159
Author: Alan Modra <amodra@gmail.com>
Date:   Wed Aug 23 08:34:12 2023 +0930

    kvx: ubsan: integer overflow
    
    This fixes a few places where ubsan complains about signed integer
    overflow when running the testsuite, and that clz(0) is undefined.
    When fixing the clz problem, I also noticed that we'd get complaints
    if pval is ever LLONG_MIN.  Fix that by using unsigned arithmetic.
    
            * config/kvx-parse.c (get_token_class): Avoid signed overflow.
            Don't clz(0).
            * config/tc-kvx.c (PARALLEL_BIT): Avoid signed overflow.

Diff:
---
 gas/config/kvx-parse.c | 6 +++---
 gas/config/tc-kvx.c    | 2 +-
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/gas/config/kvx-parse.c b/gas/config/kvx-parse.c
index ec3f912c476..fe0e2aee737 100644
--- a/gas/config/kvx-parse.c
+++ b/gas/config/kvx-parse.c
@@ -515,9 +515,9 @@ get_token_class (struct token_s *token, struct token_classes *classes, int insn_
 	? token->val
 	: strtoull (tok + (tok[0] == '-') + (tok[0] == '+'), NULL, 0);
       long long val = uval;
-      long long pval = val < 0 ? -val : val;
-      int neg_power2_p = val < 0 && !(pval & (pval - 1));
-      unsigned int len = 8 * sizeof (pval) - __builtin_clzll (pval);
+      long long pval = val < 0 ? -uval : uval;
+      int neg_power2_p = val < 0 && !(uval & (uval - 1));
+      unsigned len = pval ? 8 * sizeof (pval) - __builtin_clzll (pval) : 0;
       for (; class[cur].class_id != -1
 	  && ((unsigned int) (class[cur].sz < 0 ? - class[cur].sz - !neg_power2_p : class[cur].sz) < len
 	      || (exp.X_op == O_symbol && !has_relocation_of_size (str_hash_find (env.reloc_hash, TOKEN_NAME (class[cur].class_id))))
diff --git a/gas/config/tc-kvx.c b/gas/config/tc-kvx.c
index 3cf6b27976d..0e67ead4449 100644
--- a/gas/config/tc-kvx.c
+++ b/gas/config/tc-kvx.c
@@ -49,7 +49,7 @@ static void supported_cores (char buf[], size_t buflen);
 #define STRNEQ(x,y,n) !strncmp(((x) ? (x) : ""), ((y) ? (y) : ""),(n))
 
 /* The PARALLEL_BIT is set to 0 when an instruction is the last of a bundle. */
-#define PARALLEL_BIT (1 << 31)
+#define PARALLEL_BIT (1u << 31)
 
 /*TB begin*/
 int size_type_function = 1;