ubsan: spu: left shift of negative value
Alan Modra
amodra@gmail.com
Fri Jan 10 11:06:00 GMT 2020
Also fixes a real bug. The DECODE_INSN_I9a and DECODE_INSN_I9b both
use UNSIGNED_EXTRACT for 7 low bits of the result, but this was an
unsigned value due to "insn" being unsigned. DECODE_INSN_I9* is
therefore unsigned too, leading to a zero extension in an expression
using a bfd_vma if bfd_vma is 64 bits.
* opcode/spu.h: Formatting.
(UNSIGNED_EXTRACT): Use 1u.
(SIGNED_EXTRACT): Don't sign extend with shifts.
(DECODE_INSN_I9a, DECODE_INSN_I9b): Avoid left shift of signed value.
Keep result signed.
(DECODE_INSN_U9a, DECODE_INSN_U9b): Delete.
diff --git a/include/opcode/spu.h b/include/opcode/spu.h
index 50dce8a900..d8505ef6da 100644
--- a/include/opcode/spu.h
+++ b/include/opcode/spu.h
@@ -87,39 +87,42 @@ struct spu_opcode
int arg[5];
};
-#define SIGNED_EXTRACT(insn,size,pos) (((int)((insn) << (32-size-pos))) >> (32-size))
-#define UNSIGNED_EXTRACT(insn,size,pos) (((insn) >> pos) & ((1 << size)-1))
+#define UNSIGNED_EXTRACT(insn, size, pos) \
+ (((insn) >> (pos)) & ((1u << (size)) - 1))
+#define SIGNED_EXTRACT(insn, size, pos) \
+ (((int) UNSIGNED_EXTRACT(insn, size, pos) \
+ ^ (1 << ((size) - 1))) - (1 << ((size) - 1)))
#define DECODE_INSN_RT(insn) (insn & 0x7f)
#define DECODE_INSN_RA(insn) ((insn >> 7) & 0x7f)
#define DECODE_INSN_RB(insn) ((insn >> 14) & 0x7f)
#define DECODE_INSN_RC(insn) ((insn >> 21) & 0x7f)
-#define DECODE_INSN_I10(insn) SIGNED_EXTRACT(insn,10,14)
-#define DECODE_INSN_U10(insn) UNSIGNED_EXTRACT(insn,10,14)
+#define DECODE_INSN_I10(insn) SIGNED_EXTRACT (insn, 10, 14)
+#define DECODE_INSN_U10(insn) UNSIGNED_EXTRACT (insn, 10, 14)
/* For branching, immediate loads, hbr and lqa/stqa. */
-#define DECODE_INSN_I16(insn) SIGNED_EXTRACT(insn,16,7)
-#define DECODE_INSN_U16(insn) UNSIGNED_EXTRACT(insn,16,7)
+#define DECODE_INSN_I16(insn) SIGNED_EXTRACT (insn, 16, 7)
+#define DECODE_INSN_U16(insn) UNSIGNED_EXTRACT (insn, 16, 7)
/* for stop */
-#define DECODE_INSN_U14(insn) UNSIGNED_EXTRACT(insn,14,0)
+#define DECODE_INSN_U14(insn) UNSIGNED_EXTRACT (insn, 14, 0)
/* For ila */
-#define DECODE_INSN_I18(insn) SIGNED_EXTRACT(insn,18,7)
-#define DECODE_INSN_U18(insn) UNSIGNED_EXTRACT(insn,18,7)
+#define DECODE_INSN_I18(insn) SIGNED_EXTRACT (insn, 18, 7)
+#define DECODE_INSN_U18(insn) UNSIGNED_EXTRACT (insn, 18, 7)
/* For rotate and shift and generate control mask */
-#define DECODE_INSN_I7(insn) SIGNED_EXTRACT(insn,7,14)
-#define DECODE_INSN_U7(insn) UNSIGNED_EXTRACT(insn,7,14)
+#define DECODE_INSN_I7(insn) SIGNED_EXTRACT (insn, 7, 14)
+#define DECODE_INSN_U7(insn) UNSIGNED_EXTRACT (insn, 7, 14)
/* For float <-> int conversion */
-#define DECODE_INSN_I8(insn) SIGNED_EXTRACT(insn,8,14)
-#define DECODE_INSN_U8(insn) UNSIGNED_EXTRACT(insn,8,14)
+#define DECODE_INSN_I8(insn) SIGNED_EXTRACT (insn, 8, 14)
+#define DECODE_INSN_U8(insn) UNSIGNED_EXTRACT (insn, 8, 14)
/* For hbr */
-#define DECODE_INSN_I9a(insn) ((SIGNED_EXTRACT(insn,2,23) << 7) | UNSIGNED_EXTRACT(insn,7,0))
-#define DECODE_INSN_I9b(insn) ((SIGNED_EXTRACT(insn,2,14) << 7) | UNSIGNED_EXTRACT(insn,7,0))
-#define DECODE_INSN_U9a(insn) ((UNSIGNED_EXTRACT(insn,2,23) << 7) | UNSIGNED_EXTRACT(insn,7,0))
-#define DECODE_INSN_U9b(insn) ((UNSIGNED_EXTRACT(insn,2,14) << 7) | UNSIGNED_EXTRACT(insn,7,0))
+#define DECODE_INSN_I9a(insn) \
+ ((SIGNED_EXTRACT (insn, 2, 23) * 128) | (int) UNSIGNED_EXTRACT (insn, 7, 0))
+#define DECODE_INSN_I9b(insn) \
+ ((SIGNED_EXTRACT (insn, 2, 14) * 128) | (int) UNSIGNED_EXTRACT (insn, 7, 0))
--
Alan Modra
Australia Development Lab, IBM
More information about the Binutils
mailing list