[binutils-gdb] RISC-V: Add string length check for operands in AS

[binutils-gdb] RISC-V: Add string length check for operands in AS

[Nelson Chu]

https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;h=207cc92d92c863298c530498e2dbf71a2b5fd8ae

commit 207cc92d92c863298c530498e2dbf71a2b5fd8ae
Author: Li Xu <xuli1@eswincomputing.com>
Date:   Wed Dec 14 07:32:40 2022 +0000

    RISC-V: Add string length check for operands in AS
    
    The current AS accepts invalid operands due to miss of operands length check.
    For example, "e6" is an invalid operand in (vsetvli a0, a1, e6, mf8, tu, ma),
    but it's still accepted by assembler.  In detail, the condition check "strncmp
    (array[i], *s, len) == 0" in arg_lookup function passes with "strncmp ("e64",
    "e6", 2)" in the case above.  So the generated encoding is same as that of
    (vsetvli a0, a1, e64, mf8, tu, ma).
    
    This patch fixes issue above by prompting an error in such case and also adds
    a new testcase.
    
    gas/ChangeLog:
    
            * config/tc-riscv.c (arg_lookup): Add string length check for operands.
            * testsuite/gas/riscv/vector-insns-fail-vsew.d: New testcase for an illegal vsew.
            * testsuite/gas/riscv/vector-insns-fail-vsew.l: Likewise.
            * testsuite/gas/riscv/vector-insns-fail-vsew.s: Likewise.

Diff:
---
 gas/config/tc-riscv.c                            | 3 ++-
 gas/testsuite/gas/riscv/vector-insns-fail-vsew.d | 3 +++
 gas/testsuite/gas/riscv/vector-insns-fail-vsew.l | 3 +++
 gas/testsuite/gas/riscv/vector-insns-fail-vsew.s | 1 +
 4 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/gas/config/tc-riscv.c b/gas/config/tc-riscv.c
index 0682eb35524..77c0d2e32ab 100644
--- a/gas/config/tc-riscv.c
+++ b/gas/config/tc-riscv.c
@@ -1206,7 +1206,8 @@ arg_lookup (char **s, const char *const *array, size_t size, unsigned *regnop)
     return false;
 
   for (i = 0; i < size; i++)
-    if (array[i] != NULL && strncmp (array[i], *s, len) == 0)
+    if (array[i] != NULL && strncmp (array[i], *s, len) == 0
+	&& array[i][len] == '\0')
       {
 	*regnop = i;
 	*s += len;
diff --git a/gas/testsuite/gas/riscv/vector-insns-fail-vsew.d b/gas/testsuite/gas/riscv/vector-insns-fail-vsew.d
new file mode 100644
index 00000000000..e0354d18392
--- /dev/null
+++ b/gas/testsuite/gas/riscv/vector-insns-fail-vsew.d
@@ -0,0 +1,3 @@
+#as: -march=rv32iv
+#source: vector-insns-fail-vsew.s
+#error_output: vector-insns-fail-vsew.l
diff --git a/gas/testsuite/gas/riscv/vector-insns-fail-vsew.l b/gas/testsuite/gas/riscv/vector-insns-fail-vsew.l
new file mode 100644
index 00000000000..87a2c22a805
--- /dev/null
+++ b/gas/testsuite/gas/riscv/vector-insns-fail-vsew.l
@@ -0,0 +1,3 @@
+.*: Assembler messages:
+.*: Error: instruction vsetvli requires absolute expression
+.*: Error: illegal operands `vsetvli a0,a1,e6,mf8,tu,ma'
diff --git a/gas/testsuite/gas/riscv/vector-insns-fail-vsew.s b/gas/testsuite/gas/riscv/vector-insns-fail-vsew.s
new file mode 100644
index 00000000000..b8f3242406f
--- /dev/null
+++ b/gas/testsuite/gas/riscv/vector-insns-fail-vsew.s
@@ -0,0 +1 @@
+	vsetvli  a0, a1, e6, mf8, tu, ma		# unrecognized vsew