bpf, x86: implement jiting of BPF_J{LT,LE,SLT,SLE}

This work implements jiting of BPF_J{LT,LE,SLT,SLE} instructions
with BPF_X/BPF_K variants for the x86_64 eBPF JIT.
Signed-off-by: NDaniel Borkmann <daniel@iogearbox.net>
Acked-by: NAlexei Starovoitov <ast@kernel.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

arch/x86/net/bpf_jit_comp.c

@@ -94,7 +94,9 @@ static int bpf_size_to_x86_bytes(int bpf_size)
 #define X86_JNE 0x75
 #define X86_JBE 0x76
 #define X86_JA  0x77
+#define X86_JL  0x7C
 #define X86_JGE 0x7D
+#define X86_JLE 0x7E
 #define X86_JG  0x7F
 
 static void bpf_flush_icache(void *start, void *end)
@@ -888,9 +890,13 @@ xadd:			if (is_imm8(insn->off))
 		case BPF_JMP | BPF_JEQ | BPF_X:
 		case BPF_JMP | BPF_JNE | BPF_X:
 		case BPF_JMP | BPF_JGT | BPF_X:
+		case BPF_JMP | BPF_JLT | BPF_X:
 		case BPF_JMP | BPF_JGE | BPF_X:
+		case BPF_JMP | BPF_JLE | BPF_X:
 		case BPF_JMP | BPF_JSGT | BPF_X:
+		case BPF_JMP | BPF_JSLT | BPF_X:
 		case BPF_JMP | BPF_JSGE | BPF_X:
+		case BPF_JMP | BPF_JSLE | BPF_X:
 			/* cmp dst_reg, src_reg */
 			EMIT3(add_2mod(0x48, dst_reg, src_reg), 0x39,
 			      add_2reg(0xC0, dst_reg, src_reg));
@@ -911,9 +917,13 @@ xadd:			if (is_imm8(insn->off))
 		case BPF_JMP | BPF_JEQ | BPF_K:
 		case BPF_JMP | BPF_JNE | BPF_K:
 		case BPF_JMP | BPF_JGT | BPF_K:
+		case BPF_JMP | BPF_JLT | BPF_K:
 		case BPF_JMP | BPF_JGE | BPF_K:
+		case BPF_JMP | BPF_JLE | BPF_K:
 		case BPF_JMP | BPF_JSGT | BPF_K:
+		case BPF_JMP | BPF_JSLT | BPF_K:
 		case BPF_JMP | BPF_JSGE | BPF_K:
+		case BPF_JMP | BPF_JSLE | BPF_K:
 			/* cmp dst_reg, imm8/32 */
 			EMIT1(add_1mod(0x48, dst_reg));
 
@@ -935,18 +945,34 @@ xadd:			if (is_imm8(insn->off))
 				/* GT is unsigned '>', JA in x86 */
 				jmp_cond = X86_JA;
 				break;
+			case BPF_JLT:
+				/* LT is unsigned '<', JB in x86 */
+				jmp_cond = X86_JB;
+				break;
 			case BPF_JGE:
 				/* GE is unsigned '>=', JAE in x86 */
 				jmp_cond = X86_JAE;
 				break;
+			case BPF_JLE:
+				/* LE is unsigned '<=', JBE in x86 */
+				jmp_cond = X86_JBE;
+				break;
 			case BPF_JSGT:
 				/* signed '>', GT in x86 */
 				jmp_cond = X86_JG;
 				break;
+			case BPF_JSLT:
+				/* signed '<', LT in x86 */
+				jmp_cond = X86_JL;
+				break;
 			case BPF_JSGE:
 				/* signed '>=', GE in x86 */
 				jmp_cond = X86_JGE;
 				break;
+			case BPF_JSLE:
+				/* signed '<=', LE in x86 */
+				jmp_cond = X86_JLE;
+				break;
 			default: /* to silence gcc warning */
 				return -EFAULT;
 			}