[binutils-gdb] ubsan: ia64: left shift of negative value

[Alan Modra]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=8ff23dba80b80a9f47d75dd43812e041f6674763

commit 8ff23dba80b80a9f47d75dd43812e041f6674763
Author: Alan Modra <amodra@gmail.com>
Date:   Tue Dec 10 17:57:14 2019 +1030

    ubsan: ia64: left shift of negative value
    
    Here, since val is signed:
       *valuep = (val << scale);
    
    	* cpu-ia64-opc.c (ext_imms_scaled): Avoid undefined left shift
    	of negative values by using unsigned vars.

Diff:
---
 bfd/ChangeLog      | 5 +++++
 bfd/cpu-ia64-opc.c | 6 +++---
 2 files changed, 8 insertions(+), 3 deletions(-)

diff --git a/bfd/ChangeLog b/bfd/ChangeLog
index 50c878b..17ad441 100644
--- a/bfd/ChangeLog
+++ b/bfd/ChangeLog
@@ -1,3 +1,8 @@
+2019-12-11  Alan Modra  <amodra@gmail.com>
+
+	* cpu-ia64-opc.c (ext_imms_scaled): Avoid undefined left shift
+	of negative values by using unsigned vars.
+
 2019-12-07  Alan Modra  <amodra@gmail.com>
 
 	PR 25236
diff --git a/bfd/cpu-ia64-opc.c b/bfd/cpu-ia64-opc.c
index 84ee0e2..8df90be 100644
--- a/bfd/cpu-ia64-opc.c
+++ b/bfd/cpu-ia64-opc.c
@@ -186,7 +186,7 @@ ext_imms_scaled (const struct ia64_operand *self, ia64_insn code,
 		 ia64_insn *valuep, int scale)
 {
   int i, bits = 0, total = 0;
-  BFD_HOST_64_BIT val = 0, sign;
+  BFD_HOST_U_64_BIT val = 0, sign;
 
   for (i = 0; i < NELEMS (self->field) && self->field[i].bits; ++i)
     {
@@ -196,10 +196,10 @@ ext_imms_scaled (const struct ia64_operand *self, ia64_insn code,
       total += bits;
     }
   /* sign extend: */
-  sign = (BFD_HOST_64_BIT) 1 << (total - 1);
+  sign = (BFD_HOST_U_64_BIT) 1 << (total - 1);
   val = (val ^ sign) - sign;
 
-  *valuep = (val << scale);
+  *valuep = val << scale;
   return 0;
 }