diff options
author | Jonathan Nieder <jrnieder@gmail.com> | 2009-12-13 16:04:38 -0600 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2009-12-15 20:35:49 +0100 |
commit | 23637568ad0c9b5ab0ad27d2f2f26d1e9282c527 (patch) | |
tree | 20f46ea8ae7df6a50bdbde3ed3f2fcda1623db4b | |
parent | bf08b3b1a1d06e92036a0c4f144b64fe6be2bffa (diff) |
x86: Fix kprobes build with non-gawk awk
The instruction attribute table generator fails when run by mawk
or original-awk:
$ mawk -f arch/x86/tools/gen-insn-attr-x86.awk \
arch/x86/lib/x86-opcode-map.txt > /dev/null
Semantic error at 240: Second IMM error
$ echo $?
1
Line 240 contains "c8: ENTER Iw,Ib", which indicates that this
instruction has two immediate operands, the second of which is
one byte. The script loops through the immediate operands using
a for loop.
Unfortunately, there is no guarantee in awk that a for (variable
in array) loop will return the indices in increasing order.
Internally, both original-awk and mawk iterate over a hash table
for this purpose, and both implementations happen to produce the
index 2 before 1. The supposed second immediate operand is more
than one byte wide, producing the error.
So loop over the indices in increasing order instead. As a
side-effect, with mawk this means the silly two-entry hash table
never has to be built.
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Acked-by Masami Hiramatsu <mhiramat@redhat.com>
Cc: Jim Keniston <jkenisto@us.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20091213220437.GA27718@progeny.tock>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r-- | arch/x86/tools/gen-insn-attr-x86.awk | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/arch/x86/tools/gen-insn-attr-x86.awk b/arch/x86/tools/gen-insn-attr-x86.awk index e34e92a28eb..7a6850683c3 100644 --- a/arch/x86/tools/gen-insn-attr-x86.awk +++ b/arch/x86/tools/gen-insn-attr-x86.awk @@ -226,12 +226,12 @@ function add_flags(old,new) { } # convert operands to flags. -function convert_operands(opnd, i,imm,mod) +function convert_operands(count,opnd, i,j,imm,mod) { imm = null mod = null - for (i in opnd) { - i = opnd[i] + for (j = 1; j <= count; j++) { + i = opnd[j] if (match(i, imm_expr) == 1) { if (!imm_flag[i]) semantic_error("Unknown imm opnd: " i) @@ -282,8 +282,8 @@ function convert_operands(opnd, i,imm,mod) # parse one opcode if (match($i, opnd_expr)) { opnd = $i - split($(i++), opnds, ",") - flags = convert_operands(opnds) + count = split($(i++), opnds, ",") + flags = convert_operands(count, opnds) } if (match($i, ext_expr)) ext = $(i++) |