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Diffstat (limited to 'arch/x86/net/bpf_jit_comp32.c')
-rw-r--r--arch/x86/net/bpf_jit_comp32.c2553
1 files changed, 2553 insertions, 0 deletions
diff --git a/arch/x86/net/bpf_jit_comp32.c b/arch/x86/net/bpf_jit_comp32.c
new file mode 100644
index 000000000000..61e61341b777
--- /dev/null
+++ b/arch/x86/net/bpf_jit_comp32.c
@@ -0,0 +1,2553 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Just-In-Time compiler for eBPF filters on IA32 (32bit x86)
+ *
+ * Author: Wang YanQing (udknight@gmail.com)
+ * The code based on code and ideas from:
+ * Eric Dumazet (eric.dumazet@gmail.com)
+ * and from:
+ * Shubham Bansal <illusionist.neo@gmail.com>
+ */
+
+#include <linux/netdevice.h>
+#include <linux/filter.h>
+#include <linux/if_vlan.h>
+#include <asm/cacheflush.h>
+#include <asm/set_memory.h>
+#include <asm/nospec-branch.h>
+#include <linux/bpf.h>
+
+/*
+ * eBPF prog stack layout:
+ *
+ * high
+ * original ESP => +-----+
+ * | | callee saved registers
+ * +-----+
+ * | ... | eBPF JIT scratch space
+ * BPF_FP,IA32_EBP => +-----+
+ * | ... | eBPF prog stack
+ * +-----+
+ * |RSVD | JIT scratchpad
+ * current ESP => +-----+
+ * | |
+ * | ... | Function call stack
+ * | |
+ * +-----+
+ * low
+ *
+ * The callee saved registers:
+ *
+ * high
+ * original ESP => +------------------+ \
+ * | ebp | |
+ * current EBP => +------------------+ } callee saved registers
+ * | ebx,esi,edi | |
+ * +------------------+ /
+ * low
+ */
+
+static u8 *emit_code(u8 *ptr, u32 bytes, unsigned int len)
+{
+ if (len == 1)
+ *ptr = bytes;
+ else if (len == 2)
+ *(u16 *)ptr = bytes;
+ else {
+ *(u32 *)ptr = bytes;
+ barrier();
+ }
+ return ptr + len;
+}
+
+#define EMIT(bytes, len) \
+ do { prog = emit_code(prog, bytes, len); cnt += len; } while (0)
+
+#define EMIT1(b1) EMIT(b1, 1)
+#define EMIT2(b1, b2) EMIT((b1) + ((b2) << 8), 2)
+#define EMIT3(b1, b2, b3) EMIT((b1) + ((b2) << 8) + ((b3) << 16), 3)
+#define EMIT4(b1, b2, b3, b4) \
+ EMIT((b1) + ((b2) << 8) + ((b3) << 16) + ((b4) << 24), 4)
+
+#define EMIT1_off32(b1, off) \
+ do { EMIT1(b1); EMIT(off, 4); } while (0)
+#define EMIT2_off32(b1, b2, off) \
+ do { EMIT2(b1, b2); EMIT(off, 4); } while (0)
+#define EMIT3_off32(b1, b2, b3, off) \
+ do { EMIT3(b1, b2, b3); EMIT(off, 4); } while (0)
+#define EMIT4_off32(b1, b2, b3, b4, off) \
+ do { EMIT4(b1, b2, b3, b4); EMIT(off, 4); } while (0)
+
+#define jmp_label(label, jmp_insn_len) (label - cnt - jmp_insn_len)
+
+static bool is_imm8(int value)
+{
+ return value <= 127 && value >= -128;
+}
+
+static bool is_simm32(s64 value)
+{
+ return value == (s64) (s32) value;
+}
+
+#define STACK_OFFSET(k) (k)
+#define TCALL_CNT (MAX_BPF_JIT_REG + 0) /* Tail Call Count */
+
+#define IA32_EAX (0x0)
+#define IA32_EBX (0x3)
+#define IA32_ECX (0x1)
+#define IA32_EDX (0x2)
+#define IA32_ESI (0x6)
+#define IA32_EDI (0x7)
+#define IA32_EBP (0x5)
+#define IA32_ESP (0x4)
+
+/*
+ * List of x86 cond jumps opcodes (. + s8)
+ * Add 0x10 (and an extra 0x0f) to generate far jumps (. + s32)
+ */
+#define IA32_JB 0x72
+#define IA32_JAE 0x73
+#define IA32_JE 0x74
+#define IA32_JNE 0x75
+#define IA32_JBE 0x76
+#define IA32_JA 0x77
+#define IA32_JL 0x7C
+#define IA32_JGE 0x7D
+#define IA32_JLE 0x7E
+#define IA32_JG 0x7F
+
+/*
+ * Map eBPF registers to IA32 32bit registers or stack scratch space.
+ *
+ * 1. All the registers, R0-R10, are mapped to scratch space on stack.
+ * 2. We need two 64 bit temp registers to do complex operations on eBPF
+ * registers.
+ * 3. For performance reason, the BPF_REG_AX for blinding constant, is
+ * mapped to real hardware register pair, IA32_ESI and IA32_EDI.
+ *
+ * As the eBPF registers are all 64 bit registers and IA32 has only 32 bit
+ * registers, we have to map each eBPF registers with two IA32 32 bit regs
+ * or scratch memory space and we have to build eBPF 64 bit register from those.
+ *
+ * We use IA32_EAX, IA32_EDX, IA32_ECX, IA32_EBX as temporary registers.
+ */
+static const u8 bpf2ia32[][2] = {
+ /* Return value from in-kernel function, and exit value from eBPF */
+ [BPF_REG_0] = {STACK_OFFSET(0), STACK_OFFSET(4)},
+
+ /* The arguments from eBPF program to in-kernel function */
+ /* Stored on stack scratch space */
+ [BPF_REG_1] = {STACK_OFFSET(8), STACK_OFFSET(12)},
+ [BPF_REG_2] = {STACK_OFFSET(16), STACK_OFFSET(20)},
+ [BPF_REG_3] = {STACK_OFFSET(24), STACK_OFFSET(28)},
+ [BPF_REG_4] = {STACK_OFFSET(32), STACK_OFFSET(36)},
+ [BPF_REG_5] = {STACK_OFFSET(40), STACK_OFFSET(44)},
+
+ /* Callee saved registers that in-kernel function will preserve */
+ /* Stored on stack scratch space */
+ [BPF_REG_6] = {STACK_OFFSET(48), STACK_OFFSET(52)},
+ [BPF_REG_7] = {STACK_OFFSET(56), STACK_OFFSET(60)},
+ [BPF_REG_8] = {STACK_OFFSET(64), STACK_OFFSET(68)},
+ [BPF_REG_9] = {STACK_OFFSET(72), STACK_OFFSET(76)},
+
+ /* Read only Frame Pointer to access Stack */
+ [BPF_REG_FP] = {STACK_OFFSET(80), STACK_OFFSET(84)},
+
+ /* Temporary register for blinding constants. */
+ [BPF_REG_AX] = {IA32_ESI, IA32_EDI},
+
+ /* Tail call count. Stored on stack scratch space. */
+ [TCALL_CNT] = {STACK_OFFSET(88), STACK_OFFSET(92)},
+};
+
+#define dst_lo dst[0]
+#define dst_hi dst[1]
+#define src_lo src[0]
+#define src_hi src[1]
+
+#define STACK_ALIGNMENT 8
+/*
+ * Stack space for BPF_REG_1, BPF_REG_2, BPF_REG_3, BPF_REG_4,
+ * BPF_REG_5, BPF_REG_6, BPF_REG_7, BPF_REG_8, BPF_REG_9,
+ * BPF_REG_FP, BPF_REG_AX and Tail call counts.
+ */
+#define SCRATCH_SIZE 96
+
+/* Total stack size used in JITed code */
+#define _STACK_SIZE \
+ (stack_depth + \
+ + SCRATCH_SIZE + \
+ + 4 /* Extra space for skb_copy_bits buffer */)
+
+#define STACK_SIZE ALIGN(_STACK_SIZE, STACK_ALIGNMENT)
+
+/* Get the offset of eBPF REGISTERs stored on scratch space. */
+#define STACK_VAR(off) (off)
+
+/* Offset of skb_copy_bits buffer */
+#define SKB_BUFFER STACK_VAR(SCRATCH_SIZE)
+
+/* Encode 'dst_reg' register into IA32 opcode 'byte' */
+static u8 add_1reg(u8 byte, u32 dst_reg)
+{
+ return byte + dst_reg;
+}
+
+/* Encode 'dst_reg' and 'src_reg' registers into IA32 opcode 'byte' */
+static u8 add_2reg(u8 byte, u32 dst_reg, u32 src_reg)
+{
+ return byte + dst_reg + (src_reg << 3);
+}
+
+static void jit_fill_hole(void *area, unsigned int size)
+{
+ /* Fill whole space with int3 instructions */
+ memset(area, 0xcc, size);
+}
+
+static inline void emit_ia32_mov_i(const u8 dst, const u32 val, bool dstk,
+ u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+
+ if (dstk) {
+ if (val == 0) {
+ /* xor eax,eax */
+ EMIT2(0x33, add_2reg(0xC0, IA32_EAX, IA32_EAX));
+ /* mov dword ptr [ebp+off],eax */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst));
+ } else {
+ EMIT3_off32(0xC7, add_1reg(0x40, IA32_EBP),
+ STACK_VAR(dst), val);
+ }
+ } else {
+ if (val == 0)
+ EMIT2(0x33, add_2reg(0xC0, dst, dst));
+ else
+ EMIT2_off32(0xC7, add_1reg(0xC0, dst),
+ val);
+ }
+ *pprog = prog;
+}
+
+/* dst = imm (4 bytes)*/
+static inline void emit_ia32_mov_r(const u8 dst, const u8 src, bool dstk,
+ bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 sreg = sstk ? IA32_EAX : src;
+
+ if (sstk)
+ /* mov eax,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(src));
+ if (dstk)
+ /* mov dword ptr [ebp+off],eax */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, sreg), STACK_VAR(dst));
+ else
+ /* mov dst,sreg */
+ EMIT2(0x89, add_2reg(0xC0, dst, sreg));
+
+ *pprog = prog;
+}
+
+/* dst = src */
+static inline void emit_ia32_mov_r64(const bool is64, const u8 dst[],
+ const u8 src[], bool dstk,
+ bool sstk, u8 **pprog)
+{
+ emit_ia32_mov_r(dst_lo, src_lo, dstk, sstk, pprog);
+ if (is64)
+ /* complete 8 byte move */
+ emit_ia32_mov_r(dst_hi, src_hi, dstk, sstk, pprog);
+ else
+ /* zero out high 4 bytes */
+ emit_ia32_mov_i(dst_hi, 0, dstk, pprog);
+}
+
+/* Sign extended move */
+static inline void emit_ia32_mov_i64(const bool is64, const u8 dst[],
+ const u32 val, bool dstk, u8 **pprog)
+{
+ u32 hi = 0;
+
+ if (is64 && (val & (1<<31)))
+ hi = (u32)~0;
+ emit_ia32_mov_i(dst_lo, val, dstk, pprog);
+ emit_ia32_mov_i(dst_hi, hi, dstk, pprog);
+}
+
+/*
+ * ALU operation (32 bit)
+ * dst = dst * src
+ */
+static inline void emit_ia32_mul_r(const u8 dst, const u8 src, bool dstk,
+ bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 sreg = sstk ? IA32_ECX : src;
+
+ if (sstk)
+ /* mov ecx,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(src));
+
+ if (dstk)
+ /* mov eax,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(dst));
+ else
+ /* mov eax,dst */
+ EMIT2(0x8B, add_2reg(0xC0, dst, IA32_EAX));
+
+
+ EMIT2(0xF7, add_1reg(0xE0, sreg));
+
+ if (dstk)
+ /* mov dword ptr [ebp+off],eax */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst));
+ else
+ /* mov dst,eax */
+ EMIT2(0x89, add_2reg(0xC0, dst, IA32_EAX));
+
+ *pprog = prog;
+}
+
+static inline void emit_ia32_to_le_r64(const u8 dst[], s32 val,
+ bool dstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk && val != 64) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+ switch (val) {
+ case 16:
+ /*
+ * Emit 'movzwl eax,ax' to zero extend 16-bit
+ * into 64 bit
+ */
+ EMIT2(0x0F, 0xB7);
+ EMIT1(add_2reg(0xC0, dreg_lo, dreg_lo));
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+ break;
+ case 32:
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+ break;
+ case 64:
+ /* nop */
+ break;
+ }
+
+ if (dstk && val != 64) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ *pprog = prog;
+}
+
+static inline void emit_ia32_to_be_r64(const u8 dst[], s32 val,
+ bool dstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+ switch (val) {
+ case 16:
+ /* Emit 'ror %ax, 8' to swap lower 2 bytes */
+ EMIT1(0x66);
+ EMIT3(0xC1, add_1reg(0xC8, dreg_lo), 8);
+
+ EMIT2(0x0F, 0xB7);
+ EMIT1(add_2reg(0xC0, dreg_lo, dreg_lo));
+
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+ break;
+ case 32:
+ /* Emit 'bswap eax' to swap lower 4 bytes */
+ EMIT1(0x0F);
+ EMIT1(add_1reg(0xC8, dreg_lo));
+
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+ break;
+ case 64:
+ /* Emit 'bswap eax' to swap lower 4 bytes */
+ EMIT1(0x0F);
+ EMIT1(add_1reg(0xC8, dreg_lo));
+
+ /* Emit 'bswap edx' to swap lower 4 bytes */
+ EMIT1(0x0F);
+ EMIT1(add_1reg(0xC8, dreg_hi));
+
+ /* mov ecx,dreg_hi */
+ EMIT2(0x89, add_2reg(0xC0, IA32_ECX, dreg_hi));
+ /* mov dreg_hi,dreg_lo */
+ EMIT2(0x89, add_2reg(0xC0, dreg_hi, dreg_lo));
+ /* mov dreg_lo,ecx */
+ EMIT2(0x89, add_2reg(0xC0, dreg_lo, IA32_ECX));
+
+ break;
+ }
+ if (dstk) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ *pprog = prog;
+}
+
+/*
+ * ALU operation (32 bit)
+ * dst = dst (div|mod) src
+ */
+static inline void emit_ia32_div_mod_r(const u8 op, const u8 dst, const u8 src,
+ bool dstk, bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+
+ if (sstk)
+ /* mov ecx,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
+ STACK_VAR(src));
+ else if (src != IA32_ECX)
+ /* mov ecx,src */
+ EMIT2(0x8B, add_2reg(0xC0, src, IA32_ECX));
+
+ if (dstk)
+ /* mov eax,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst));
+ else
+ /* mov eax,dst */
+ EMIT2(0x8B, add_2reg(0xC0, dst, IA32_EAX));
+
+ /* xor edx,edx */
+ EMIT2(0x31, add_2reg(0xC0, IA32_EDX, IA32_EDX));
+ /* div ecx */
+ EMIT2(0xF7, add_1reg(0xF0, IA32_ECX));
+
+ if (op == BPF_MOD) {
+ if (dstk)
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst));
+ else
+ EMIT2(0x89, add_2reg(0xC0, dst, IA32_EDX));
+ } else {
+ if (dstk)
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst));
+ else
+ EMIT2(0x89, add_2reg(0xC0, dst, IA32_EAX));
+ }
+ *pprog = prog;
+}
+
+/*
+ * ALU operation (32 bit)
+ * dst = dst (shift) src
+ */
+static inline void emit_ia32_shift_r(const u8 op, const u8 dst, const u8 src,
+ bool dstk, bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 dreg = dstk ? IA32_EAX : dst;
+ u8 b2;
+
+ if (dstk)
+ /* mov eax,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(dst));
+
+ if (sstk)
+ /* mov ecx,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX), STACK_VAR(src));
+ else if (src != IA32_ECX)
+ /* mov ecx,src */
+ EMIT2(0x8B, add_2reg(0xC0, src, IA32_ECX));
+
+ switch (op) {
+ case BPF_LSH:
+ b2 = 0xE0; break;
+ case BPF_RSH:
+ b2 = 0xE8; break;
+ case BPF_ARSH:
+ b2 = 0xF8; break;
+ default:
+ return;
+ }
+ EMIT2(0xD3, add_1reg(b2, dreg));
+
+ if (dstk)
+ /* mov dword ptr [ebp+off],dreg */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg), STACK_VAR(dst));
+ *pprog = prog;
+}
+
+/*
+ * ALU operation (32 bit)
+ * dst = dst (op) src
+ */
+static inline void emit_ia32_alu_r(const bool is64, const bool hi, const u8 op,
+ const u8 dst, const u8 src, bool dstk,
+ bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 sreg = sstk ? IA32_EAX : src;
+ u8 dreg = dstk ? IA32_EDX : dst;
+
+ if (sstk)
+ /* mov eax,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(src));
+
+ if (dstk)
+ /* mov eax,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX), STACK_VAR(dst));
+
+ switch (BPF_OP(op)) {
+ /* dst = dst + src */
+ case BPF_ADD:
+ if (hi && is64)
+ EMIT2(0x11, add_2reg(0xC0, dreg, sreg));
+ else
+ EMIT2(0x01, add_2reg(0xC0, dreg, sreg));
+ break;
+ /* dst = dst - src */
+ case BPF_SUB:
+ if (hi && is64)
+ EMIT2(0x19, add_2reg(0xC0, dreg, sreg));
+ else
+ EMIT2(0x29, add_2reg(0xC0, dreg, sreg));
+ break;
+ /* dst = dst | src */
+ case BPF_OR:
+ EMIT2(0x09, add_2reg(0xC0, dreg, sreg));
+ break;
+ /* dst = dst & src */
+ case BPF_AND:
+ EMIT2(0x21, add_2reg(0xC0, dreg, sreg));
+ break;
+ /* dst = dst ^ src */
+ case BPF_XOR:
+ EMIT2(0x31, add_2reg(0xC0, dreg, sreg));
+ break;
+ }
+
+ if (dstk)
+ /* mov dword ptr [ebp+off],dreg */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg),
+ STACK_VAR(dst));
+ *pprog = prog;
+}
+
+/* ALU operation (64 bit) */
+static inline void emit_ia32_alu_r64(const bool is64, const u8 op,
+ const u8 dst[], const u8 src[],
+ bool dstk, bool sstk,
+ u8 **pprog)
+{
+ u8 *prog = *pprog;
+
+ emit_ia32_alu_r(is64, false, op, dst_lo, src_lo, dstk, sstk, &prog);
+ if (is64)
+ emit_ia32_alu_r(is64, true, op, dst_hi, src_hi, dstk, sstk,
+ &prog);
+ else
+ emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
+ *pprog = prog;
+}
+
+/*
+ * ALU operation (32 bit)
+ * dst = dst (op) val
+ */
+static inline void emit_ia32_alu_i(const bool is64, const bool hi, const u8 op,
+ const u8 dst, const s32 val, bool dstk,
+ u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 dreg = dstk ? IA32_EAX : dst;
+ u8 sreg = IA32_EDX;
+
+ if (dstk)
+ /* mov eax,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX), STACK_VAR(dst));
+
+ if (!is_imm8(val))
+ /* mov edx,imm32*/
+ EMIT2_off32(0xC7, add_1reg(0xC0, IA32_EDX), val);
+
+ switch (op) {
+ /* dst = dst + val */
+ case BPF_ADD:
+ if (hi && is64) {
+ if (is_imm8(val))
+ EMIT3(0x83, add_1reg(0xD0, dreg), val);
+ else
+ EMIT2(0x11, add_2reg(0xC0, dreg, sreg));
+ } else {
+ if (is_imm8(val))
+ EMIT3(0x83, add_1reg(0xC0, dreg), val);
+ else
+ EMIT2(0x01, add_2reg(0xC0, dreg, sreg));
+ }
+ break;
+ /* dst = dst - val */
+ case BPF_SUB:
+ if (hi && is64) {
+ if (is_imm8(val))
+ EMIT3(0x83, add_1reg(0xD8, dreg), val);
+ else
+ EMIT2(0x19, add_2reg(0xC0, dreg, sreg));
+ } else {
+ if (is_imm8(val))
+ EMIT3(0x83, add_1reg(0xE8, dreg), val);
+ else
+ EMIT2(0x29, add_2reg(0xC0, dreg, sreg));
+ }
+ break;
+ /* dst = dst | val */
+ case BPF_OR:
+ if (is_imm8(val))
+ EMIT3(0x83, add_1reg(0xC8, dreg), val);
+ else
+ EMIT2(0x09, add_2reg(0xC0, dreg, sreg));
+ break;
+ /* dst = dst & val */
+ case BPF_AND:
+ if (is_imm8(val))
+ EMIT3(0x83, add_1reg(0xE0, dreg), val);
+ else
+ EMIT2(0x21, add_2reg(0xC0, dreg, sreg));
+ break;
+ /* dst = dst ^ val */
+ case BPF_XOR:
+ if (is_imm8(val))
+ EMIT3(0x83, add_1reg(0xF0, dreg), val);
+ else
+ EMIT2(0x31, add_2reg(0xC0, dreg, sreg));
+ break;
+ case BPF_NEG:
+ EMIT2(0xF7, add_1reg(0xD8, dreg));
+ break;
+ }
+
+ if (dstk)
+ /* mov dword ptr [ebp+off],dreg */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg),
+ STACK_VAR(dst));
+ *pprog = prog;
+}
+
+/* ALU operation (64 bit) */
+static inline void emit_ia32_alu_i64(const bool is64, const u8 op,
+ const u8 dst[], const u32 val,
+ bool dstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ u32 hi = 0;
+
+ if (is64 && (val & (1<<31)))
+ hi = (u32)~0;
+
+ emit_ia32_alu_i(is64, false, op, dst_lo, val, dstk, &prog);
+ if (is64)
+ emit_ia32_alu_i(is64, true, op, dst_hi, hi, dstk, &prog);
+ else
+ emit_ia32_mov_i(dst_hi, 0, dstk, &prog);
+
+ *pprog = prog;
+}
+
+/* dst = ~dst (64 bit) */
+static inline void emit_ia32_neg64(const u8 dst[], bool dstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+
+ /* xor ecx,ecx */
+ EMIT2(0x31, add_2reg(0xC0, IA32_ECX, IA32_ECX));
+ /* sub dreg_lo,ecx */
+ EMIT2(0x2B, add_2reg(0xC0, dreg_lo, IA32_ECX));
+ /* mov dreg_lo,ecx */
+ EMIT2(0x89, add_2reg(0xC0, dreg_lo, IA32_ECX));
+
+ /* xor ecx,ecx */
+ EMIT2(0x31, add_2reg(0xC0, IA32_ECX, IA32_ECX));
+ /* sbb dreg_hi,ecx */
+ EMIT2(0x19, add_2reg(0xC0, dreg_hi, IA32_ECX));
+ /* mov dreg_hi,ecx */
+ EMIT2(0x89, add_2reg(0xC0, dreg_hi, IA32_ECX));
+
+ if (dstk) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ *pprog = prog;
+}
+
+/* dst = dst << src */
+static inline void emit_ia32_lsh_r64(const u8 dst[], const u8 src[],
+ bool dstk, bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ static int jmp_label1 = -1;
+ static int jmp_label2 = -1;
+ static int jmp_label3 = -1;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+
+ if (sstk)
+ /* mov ecx,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
+ STACK_VAR(src_lo));
+ else
+ /* mov ecx,src_lo */
+ EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_ECX));
+
+ /* cmp ecx,32 */
+ EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 32);
+ /* Jumps when >= 32 */
+ if (is_imm8(jmp_label(jmp_label1, 2)))
+ EMIT2(IA32_JAE, jmp_label(jmp_label1, 2));
+ else
+ EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label1, 6));
+
+ /* < 32 */
+ /* shl dreg_hi,cl */
+ EMIT2(0xD3, add_1reg(0xE0, dreg_hi));
+ /* mov ebx,dreg_lo */
+ EMIT2(0x8B, add_2reg(0xC0, dreg_lo, IA32_EBX));
+ /* shl dreg_lo,cl */
+ EMIT2(0xD3, add_1reg(0xE0, dreg_lo));
+
+ /* IA32_ECX = -IA32_ECX + 32 */
+ /* neg ecx */
+ EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
+ /* add ecx,32 */
+ EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
+
+ /* shr ebx,cl */
+ EMIT2(0xD3, add_1reg(0xE8, IA32_EBX));
+ /* or dreg_hi,ebx */
+ EMIT2(0x09, add_2reg(0xC0, dreg_hi, IA32_EBX));
+
+ /* goto out; */
+ if (is_imm8(jmp_label(jmp_label3, 2)))
+ EMIT2(0xEB, jmp_label(jmp_label3, 2));
+ else
+ EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
+
+ /* >= 32 */
+ if (jmp_label1 == -1)
+ jmp_label1 = cnt;
+
+ /* cmp ecx,64 */
+ EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 64);
+ /* Jumps when >= 64 */
+ if (is_imm8(jmp_label(jmp_label2, 2)))
+ EMIT2(IA32_JAE, jmp_label(jmp_label2, 2));
+ else
+ EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label2, 6));
+
+ /* >= 32 && < 64 */
+ /* sub ecx,32 */
+ EMIT3(0x83, add_1reg(0xE8, IA32_ECX), 32);
+ /* shl dreg_lo,cl */
+ EMIT2(0xD3, add_1reg(0xE0, dreg_lo));
+ /* mov dreg_hi,dreg_lo */
+ EMIT2(0x89, add_2reg(0xC0, dreg_hi, dreg_lo));
+
+ /* xor dreg_lo,dreg_lo */
+ EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
+
+ /* goto out; */
+ if (is_imm8(jmp_label(jmp_label3, 2)))
+ EMIT2(0xEB, jmp_label(jmp_label3, 2));
+ else
+ EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
+
+ /* >= 64 */
+ if (jmp_label2 == -1)
+ jmp_label2 = cnt;
+ /* xor dreg_lo,dreg_lo */
+ EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+
+ if (jmp_label3 == -1)
+ jmp_label3 = cnt;
+
+ if (dstk) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ /* out: */
+ *pprog = prog;
+}
+
+/* dst = dst >> src (signed)*/
+static inline void emit_ia32_arsh_r64(const u8 dst[], const u8 src[],
+ bool dstk, bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ static int jmp_label1 = -1;
+ static int jmp_label2 = -1;
+ static int jmp_label3 = -1;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+
+ if (sstk)
+ /* mov ecx,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
+ STACK_VAR(src_lo));
+ else
+ /* mov ecx,src_lo */
+ EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_ECX));
+
+ /* cmp ecx,32 */
+ EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 32);
+ /* Jumps when >= 32 */
+ if (is_imm8(jmp_label(jmp_label1, 2)))
+ EMIT2(IA32_JAE, jmp_label(jmp_label1, 2));
+ else
+ EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label1, 6));
+
+ /* < 32 */
+ /* lshr dreg_lo,cl */
+ EMIT2(0xD3, add_1reg(0xE8, dreg_lo));
+ /* mov ebx,dreg_hi */
+ EMIT2(0x8B, add_2reg(0xC0, dreg_hi, IA32_EBX));
+ /* ashr dreg_hi,cl */
+ EMIT2(0xD3, add_1reg(0xF8, dreg_hi));
+
+ /* IA32_ECX = -IA32_ECX + 32 */
+ /* neg ecx */
+ EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
+ /* add ecx,32 */
+ EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
+
+ /* shl ebx,cl */
+ EMIT2(0xD3, add_1reg(0xE0, IA32_EBX));
+ /* or dreg_lo,ebx */
+ EMIT2(0x09, add_2reg(0xC0, dreg_lo, IA32_EBX));
+
+ /* goto out; */
+ if (is_imm8(jmp_label(jmp_label3, 2)))
+ EMIT2(0xEB, jmp_label(jmp_label3, 2));
+ else
+ EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
+
+ /* >= 32 */
+ if (jmp_label1 == -1)
+ jmp_label1 = cnt;
+
+ /* cmp ecx,64 */
+ EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 64);
+ /* Jumps when >= 64 */
+ if (is_imm8(jmp_label(jmp_label2, 2)))
+ EMIT2(IA32_JAE, jmp_label(jmp_label2, 2));
+ else
+ EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label2, 6));
+
+ /* >= 32 && < 64 */
+ /* sub ecx,32 */
+ EMIT3(0x83, add_1reg(0xE8, IA32_ECX), 32);
+ /* ashr dreg_hi,cl */
+ EMIT2(0xD3, add_1reg(0xF8, dreg_hi));
+ /* mov dreg_lo,dreg_hi */
+ EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
+
+ /* ashr dreg_hi,imm8 */
+ EMIT3(0xC1, add_1reg(0xF8, dreg_hi), 31);
+
+ /* goto out; */
+ if (is_imm8(jmp_label(jmp_label3, 2)))
+ EMIT2(0xEB, jmp_label(jmp_label3, 2));
+ else
+ EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
+
+ /* >= 64 */
+ if (jmp_label2 == -1)
+ jmp_label2 = cnt;
+ /* ashr dreg_hi,imm8 */
+ EMIT3(0xC1, add_1reg(0xF8, dreg_hi), 31);
+ /* mov dreg_lo,dreg_hi */
+ EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
+
+ if (jmp_label3 == -1)
+ jmp_label3 = cnt;
+
+ if (dstk) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ /* out: */
+ *pprog = prog;
+}
+
+/* dst = dst >> src */
+static inline void emit_ia32_rsh_r64(const u8 dst[], const u8 src[], bool dstk,
+ bool sstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ static int jmp_label1 = -1;
+ static int jmp_label2 = -1;
+ static int jmp_label3 = -1;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+
+ if (sstk)
+ /* mov ecx,dword ptr [ebp+off] */
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_ECX),
+ STACK_VAR(src_lo));
+ else
+ /* mov ecx,src_lo */
+ EMIT2(0x8B, add_2reg(0xC0, src_lo, IA32_ECX));
+
+ /* cmp ecx,32 */
+ EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 32);
+ /* Jumps when >= 32 */
+ if (is_imm8(jmp_label(jmp_label1, 2)))
+ EMIT2(IA32_JAE, jmp_label(jmp_label1, 2));
+ else
+ EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label1, 6));
+
+ /* < 32 */
+ /* lshr dreg_lo,cl */
+ EMIT2(0xD3, add_1reg(0xE8, dreg_lo));
+ /* mov ebx,dreg_hi */
+ EMIT2(0x8B, add_2reg(0xC0, dreg_hi, IA32_EBX));
+ /* shr dreg_hi,cl */
+ EMIT2(0xD3, add_1reg(0xE8, dreg_hi));
+
+ /* IA32_ECX = -IA32_ECX + 32 */
+ /* neg ecx */
+ EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
+ /* add ecx,32 */
+ EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
+
+ /* shl ebx,cl */
+ EMIT2(0xD3, add_1reg(0xE0, IA32_EBX));
+ /* or dreg_lo,ebx */
+ EMIT2(0x09, add_2reg(0xC0, dreg_lo, IA32_EBX));
+
+ /* goto out; */
+ if (is_imm8(jmp_label(jmp_label3, 2)))
+ EMIT2(0xEB, jmp_label(jmp_label3, 2));
+ else
+ EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
+
+ /* >= 32 */
+ if (jmp_label1 == -1)
+ jmp_label1 = cnt;
+ /* cmp ecx,64 */
+ EMIT3(0x83, add_1reg(0xF8, IA32_ECX), 64);
+ /* Jumps when >= 64 */
+ if (is_imm8(jmp_label(jmp_label2, 2)))
+ EMIT2(IA32_JAE, jmp_label(jmp_label2, 2));
+ else
+ EMIT2_off32(0x0F, IA32_JAE + 0x10, jmp_label(jmp_label2, 6));
+
+ /* >= 32 && < 64 */
+ /* sub ecx,32 */
+ EMIT3(0x83, add_1reg(0xE8, IA32_ECX), 32);
+ /* shr dreg_hi,cl */
+ EMIT2(0xD3, add_1reg(0xE8, dreg_hi));
+ /* mov dreg_lo,dreg_hi */
+ EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+
+ /* goto out; */
+ if (is_imm8(jmp_label(jmp_label3, 2)))
+ EMIT2(0xEB, jmp_label(jmp_label3, 2));
+ else
+ EMIT1_off32(0xE9, jmp_label(jmp_label3, 5));
+
+ /* >= 64 */
+ if (jmp_label2 == -1)
+ jmp_label2 = cnt;
+ /* xor dreg_lo,dreg_lo */
+ EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+
+ if (jmp_label3 == -1)
+ jmp_label3 = cnt;
+
+ if (dstk) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ /* out: */
+ *pprog = prog;
+}
+
+/* dst = dst << val */
+static inline void emit_ia32_lsh_i64(const u8 dst[], const u32 val,
+ bool dstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+ /* Do LSH operation */
+ if (val < 32) {
+ /* shl dreg_hi,imm8 */
+ EMIT3(0xC1, add_1reg(0xE0, dreg_hi), val);
+ /* mov ebx,dreg_lo */
+ EMIT2(0x8B, add_2reg(0xC0, dreg_lo, IA32_EBX));
+ /* shl dreg_lo,imm8 */
+ EMIT3(0xC1, add_1reg(0xE0, dreg_lo), val);
+
+ /* IA32_ECX = 32 - val */
+ /* mov ecx,val */
+ EMIT2(0xB1, val);
+ /* movzx ecx,ecx */
+ EMIT3(0x0F, 0xB6, add_2reg(0xC0, IA32_ECX, IA32_ECX));
+ /* neg ecx */
+ EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
+ /* add ecx,32 */
+ EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
+
+ /* shr ebx,cl */
+ EMIT2(0xD3, add_1reg(0xE8, IA32_EBX));
+ /* or dreg_hi,ebx */
+ EMIT2(0x09, add_2reg(0xC0, dreg_hi, IA32_EBX));
+ } else if (val >= 32 && val < 64) {
+ u32 value = val - 32;
+
+ /* shl dreg_lo,imm8 */
+ EMIT3(0xC1, add_1reg(0xE0, dreg_lo), value);
+ /* mov dreg_hi,dreg_lo */
+ EMIT2(0x89, add_2reg(0xC0, dreg_hi, dreg_lo));
+ /* xor dreg_lo,dreg_lo */
+ EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
+ } else {
+ /* xor dreg_lo,dreg_lo */
+ EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+ }
+
+ if (dstk) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ *pprog = prog;
+}
+
+/* dst = dst >> val */
+static inline void emit_ia32_rsh_i64(const u8 dst[], const u32 val,
+ bool dstk, u8 **pprog)
+{
+ u8 *prog = *pprog;
+ int cnt = 0;
+ u8 dreg_lo = dstk ? IA32_EAX : dst_lo;
+ u8 dreg_hi = dstk ? IA32_EDX : dst_hi;
+
+ if (dstk) {
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EAX),
+ STACK_VAR(dst_lo));
+ EMIT3(0x8B, add_2reg(0x40, IA32_EBP, IA32_EDX),
+ STACK_VAR(dst_hi));
+ }
+
+ /* Do RSH operation */
+ if (val < 32) {
+ /* shr dreg_lo,imm8 */
+ EMIT3(0xC1, add_1reg(0xE8, dreg_lo), val);
+ /* mov ebx,dreg_hi */
+ EMIT2(0x8B, add_2reg(0xC0, dreg_hi, IA32_EBX));
+ /* shr dreg_hi,imm8 */
+ EMIT3(0xC1, add_1reg(0xE8, dreg_hi), val);
+
+ /* IA32_ECX = 32 - val */
+ /* mov ecx,val */
+ EMIT2(0xB1, val);
+ /* movzx ecx,ecx */
+ EMIT3(0x0F, 0xB6, add_2reg(0xC0, IA32_ECX, IA32_ECX));
+ /* neg ecx */
+ EMIT2(0xF7, add_1reg(0xD8, IA32_ECX));
+ /* add ecx,32 */
+ EMIT3(0x83, add_1reg(0xC0, IA32_ECX), 32);
+
+ /* shl ebx,cl */
+ EMIT2(0xD3, add_1reg(0xE0, IA32_EBX));
+ /* or dreg_lo,ebx */
+ EMIT2(0x09, add_2reg(0xC0, dreg_lo, IA32_EBX));
+ } else if (val >= 32 && val < 64) {
+ u32 value = val - 32;
+
+ /* shr dreg_hi,imm8 */
+ EMIT3(0xC1, add_1reg(0xE8, dreg_hi), value);
+ /* mov dreg_lo,dreg_hi */
+ EMIT2(0x89, add_2reg(0xC0, dreg_lo, dreg_hi));
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+ } else {
+ /* xor dreg_lo,dreg_lo */
+ EMIT2(0x33, add_2reg(0xC0, dreg_lo, dreg_lo));
+ /* xor dreg_hi,dreg_hi */
+ EMIT2(0x33, add_2reg(0xC0, dreg_hi, dreg_hi));
+ }
+
+ if (dstk) {
+ /* mov dword ptr [ebp+off],dreg_lo */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_lo),
+ STACK_VAR(dst_lo));
+ /* mov dword ptr [ebp+off],dreg_hi */
+ EMIT3(0x89, add_2reg(0x40, IA32_EBP, dreg_hi),
+ STACK_VAR(dst_hi));
+ }
+ *pprog = prog;
+}
+
<