Yonghong Song 830a6fb07d bpf: signal error instead of silent drop for certain invalid asm insn ... Currently, an invalid asm insn, either in an asm file or in an inline asm format, might be silently dropped. This patch fixed two places where this may happen by signaling the error so user knows what goes wrong. The following is an example to demonstrate error messages: -bash-4.2$ cat t.c int test(void *ctx) { #if defined(NO_ERROR) asm volatile("r0 = *(u16 *)skb[%0]" : : "i"(2)); #elif defined(ERROR_1) asm volatile("r20 = *(u16 *)skb[%0]" : : "i"(2)); #elif defined(ERROR_2) asm volatile("r0 = *(u16 *)(r1 + ?)" : :); #endif return 0; } -bash-4.2$ cat run.sh for macro in NO_ERROR ERROR_1 ERROR_2; do echo "===== compile for macro" $macro clang -D${macro} -O2 -target bpf -emit-llvm -S t.c echo "==llc==" llc -march=bpf -filetype=obj t.ll done -bash-4.2$ ./run.sh ===== compile for macro NO_ERROR ==llc== ===== compile for macro ERROR_1 ==llc== <inline asm>:1:2: error: invalid register/token name r20 = *(u16 *)skb[2] ^ note: !srcloc = 135 ===== compile for macro ERROR_2 ==llc== <inline asm>:1:21: error: unexpected token r0 = *(u16 *)(r1 + ?) ^ note: !srcloc = 210 -bash-4.2$ Acked-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Yonghong Song <yhs@fb.com> llvm-svn: 329849		2018-04-11 20:24:52 +00:00
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BPFAsmParser.cpp	bpf: signal error instead of silent drop for certain invalid asm insn	2018-04-11 20:24:52 +00:00
CMakeLists.txt
LLVMBuild.txt