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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * bpf_jit.h: BPF JIT compiler for PPC
4 *
5 * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
6 * 2016 Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
7 */
8#ifndef _BPF_JIT_H
9#define _BPF_JIT_H
10
11#ifndef __ASSEMBLY__
12
13#include <asm/types.h>
14#include <asm/ppc-opcode.h>
15
16#ifdef CONFIG_PPC64_ELF_ABI_V1
17#define FUNCTION_DESCR_SIZE 24
18#else
19#define FUNCTION_DESCR_SIZE 0
20#endif
21
22#define CTX_NIA(ctx) ((unsigned long)ctx->idx * 4)
23
24#define PLANT_INSTR(d, idx, instr) \
25 do { if (d) { (d)[idx] = instr; } idx++; } while (0)
26#define EMIT(instr) PLANT_INSTR(image, ctx->idx, instr)
27
28/* Long jump; (unconditional 'branch') */
29#define PPC_JMP(dest) \
30 do { \
31 long offset = (long)(dest) - CTX_NIA(ctx); \
32 if ((dest) != 0 && !is_offset_in_branch_range(offset)) { \
33 pr_err_ratelimited("Branch offset 0x%lx (@%u) out of range\n", offset, ctx->idx); \
34 return -ERANGE; \
35 } \
36 EMIT(PPC_RAW_BRANCH(offset)); \
37 } while (0)
38
39/* "cond" here covers BO:BI fields. */
40#define PPC_BCC_SHORT(cond, dest) \
41 do { \
42 long offset = (long)(dest) - CTX_NIA(ctx); \
43 if ((dest) != 0 && !is_offset_in_cond_branch_range(offset)) { \
44 pr_err_ratelimited("Conditional branch offset 0x%lx (@%u) out of range\n", offset, ctx->idx); \
45 return -ERANGE; \
46 } \
47 EMIT(PPC_INST_BRANCH_COND | (((cond) & 0x3ff) << 16) | (offset & 0xfffc)); \
48 } while (0)
49
50/* Sign-extended 32-bit immediate load */
51#define PPC_LI32(d, i) do { \
52 if ((int)(uintptr_t)(i) >= -32768 && \
53 (int)(uintptr_t)(i) < 32768) \
54 EMIT(PPC_RAW_LI(d, i)); \
55 else { \
56 EMIT(PPC_RAW_LIS(d, IMM_H(i))); \
57 if (IMM_L(i)) \
58 EMIT(PPC_RAW_ORI(d, d, IMM_L(i))); \
59 } } while(0)
60
61#ifdef CONFIG_PPC64
62#define PPC_LI64(d, i) do { \
63 if ((long)(i) >= -2147483648 && \
64 (long)(i) < 2147483648) \
65 PPC_LI32(d, i); \
66 else { \
67 if (!((uintptr_t)(i) & 0xffff800000000000ULL)) \
68 EMIT(PPC_RAW_LI(d, ((uintptr_t)(i) >> 32) & \
69 0xffff)); \
70 else { \
71 EMIT(PPC_RAW_LIS(d, ((uintptr_t)(i) >> 48))); \
72 if ((uintptr_t)(i) & 0x0000ffff00000000ULL) \
73 EMIT(PPC_RAW_ORI(d, d, \
74 ((uintptr_t)(i) >> 32) & 0xffff)); \
75 } \
76 EMIT(PPC_RAW_SLDI(d, d, 32)); \
77 if ((uintptr_t)(i) & 0x00000000ffff0000ULL) \
78 EMIT(PPC_RAW_ORIS(d, d, \
79 ((uintptr_t)(i) >> 16) & 0xffff)); \
80 if ((uintptr_t)(i) & 0x000000000000ffffULL) \
81 EMIT(PPC_RAW_ORI(d, d, (uintptr_t)(i) & \
82 0xffff)); \
83 } } while (0)
84#endif
85
86/*
87 * The fly in the ointment of code size changing from pass to pass is
88 * avoided by padding the short branch case with a NOP. If code size differs
89 * with different branch reaches we will have the issue of code moving from
90 * one pass to the next and will need a few passes to converge on a stable
91 * state.
92 */
93#define PPC_BCC(cond, dest) do { \
94 if (is_offset_in_cond_branch_range((long)(dest) - CTX_NIA(ctx))) { \
95 PPC_BCC_SHORT(cond, dest); \
96 EMIT(PPC_RAW_NOP()); \
97 } else { \
98 /* Flip the 'T or F' bit to invert comparison */ \
99 PPC_BCC_SHORT(cond ^ COND_CMP_TRUE, CTX_NIA(ctx) + 2*4); \
100 PPC_JMP(dest); \
101 } } while(0)
102
103/* To create a branch condition, select a bit of cr0... */
104#define CR0_LT 0
105#define CR0_GT 1
106#define CR0_EQ 2
107/* ...and modify BO[3] */
108#define COND_CMP_TRUE 0x100
109#define COND_CMP_FALSE 0x000
110/* Together, they make all required comparisons: */
111#define COND_GT (CR0_GT | COND_CMP_TRUE)
112#define COND_GE (CR0_LT | COND_CMP_FALSE)
113#define COND_EQ (CR0_EQ | COND_CMP_TRUE)
114#define COND_NE (CR0_EQ | COND_CMP_FALSE)
115#define COND_LT (CR0_LT | COND_CMP_TRUE)
116#define COND_LE (CR0_GT | COND_CMP_FALSE)
117
118#define SEEN_FUNC 0x20000000 /* might call external helpers */
119#define SEEN_TAILCALL 0x40000000 /* uses tail calls */
120
121struct codegen_context {
122 /*
123 * This is used to track register usage as well
124 * as calls to external helpers.
125 * - register usage is tracked with corresponding
126 * bits (r3-r31)
127 * - rest of the bits can be used to track other
128 * things -- for now, we use bits 0 to 2
129 * encoded in SEEN_* macros above
130 */
131 unsigned int seen;
132 unsigned int idx;
133 unsigned int stack_size;
134 int b2p[MAX_BPF_JIT_REG + 2];
135 unsigned int exentry_idx;
136 unsigned int alt_exit_addr;
137};
138
139#define bpf_to_ppc(r) (ctx->b2p[r])
140
141#ifdef CONFIG_PPC32
142#define BPF_FIXUP_LEN 3 /* Three instructions => 12 bytes */
143#else
144#define BPF_FIXUP_LEN 2 /* Two instructions => 8 bytes */
145#endif
146
147static inline bool bpf_is_seen_register(struct codegen_context *ctx, int i)
148{
149 return ctx->seen & (1 << (31 - i));
150}
151
152static inline void bpf_set_seen_register(struct codegen_context *ctx, int i)
153{
154 ctx->seen |= 1 << (31 - i);
155}
156
157static inline void bpf_clear_seen_register(struct codegen_context *ctx, int i)
158{
159 ctx->seen &= ~(1 << (31 - i));
160}
161
162void bpf_jit_init_reg_mapping(struct codegen_context *ctx);
163int bpf_jit_emit_func_call_rel(u32 *image, u32 *fimage, struct codegen_context *ctx, u64 func);
164int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, u32 *fimage, struct codegen_context *ctx,
165 u32 *addrs, int pass, bool extra_pass);
166void bpf_jit_build_prologue(u32 *image, struct codegen_context *ctx);
167void bpf_jit_build_epilogue(u32 *image, struct codegen_context *ctx);
168void bpf_jit_realloc_regs(struct codegen_context *ctx);
169int bpf_jit_emit_exit_insn(u32 *image, struct codegen_context *ctx, int tmp_reg, long exit_addr);
170
171int bpf_add_extable_entry(struct bpf_prog *fp, u32 *image, u32 *fimage, int pass,
172 struct codegen_context *ctx, int insn_idx,
173 int jmp_off, int dst_reg);
174
175#endif
176
177#endif
1/* bpf_jit.h: BPF JIT compiler for PPC64
2 *
3 * Copyright 2011 Matt Evans <matt@ozlabs.org>, IBM Corporation
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License
7 * as published by the Free Software Foundation; version 2
8 * of the License.
9 */
10#ifndef _BPF_JIT_H
11#define _BPF_JIT_H
12
13#ifdef CONFIG_PPC64
14#define BPF_PPC_STACK_R3_OFF 48
15#define BPF_PPC_STACK_LOCALS 32
16#define BPF_PPC_STACK_BASIC (48+64)
17#define BPF_PPC_STACK_SAVE (18*8)
18#define BPF_PPC_STACKFRAME (BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
19 BPF_PPC_STACK_SAVE)
20#define BPF_PPC_SLOWPATH_FRAME (48+64)
21#else
22#define BPF_PPC_STACK_R3_OFF 24
23#define BPF_PPC_STACK_LOCALS 16
24#define BPF_PPC_STACK_BASIC (24+32)
25#define BPF_PPC_STACK_SAVE (18*4)
26#define BPF_PPC_STACKFRAME (BPF_PPC_STACK_BASIC+BPF_PPC_STACK_LOCALS+ \
27 BPF_PPC_STACK_SAVE)
28#define BPF_PPC_SLOWPATH_FRAME (24+32)
29#endif
30
31#define REG_SZ (BITS_PER_LONG/8)
32
33/*
34 * Generated code register usage:
35 *
36 * As normal PPC C ABI (e.g. r1=sp, r2=TOC), with:
37 *
38 * skb r3 (Entry parameter)
39 * A register r4
40 * X register r5
41 * addr param r6
42 * r7-r10 scratch
43 * skb->data r14
44 * skb headlen r15 (skb->len - skb->data_len)
45 * m[0] r16
46 * m[...] ...
47 * m[15] r31
48 */
49#define r_skb 3
50#define r_ret 3
51#define r_A 4
52#define r_X 5
53#define r_addr 6
54#define r_scratch1 7
55#define r_scratch2 8
56#define r_D 14
57#define r_HL 15
58#define r_M 16
59
60#ifndef __ASSEMBLY__
61
62/*
63 * Assembly helpers from arch/powerpc/net/bpf_jit.S:
64 */
65#define DECLARE_LOAD_FUNC(func) \
66 extern u8 func[], func##_negative_offset[], func##_positive_offset[]
67
68DECLARE_LOAD_FUNC(sk_load_word);
69DECLARE_LOAD_FUNC(sk_load_half);
70DECLARE_LOAD_FUNC(sk_load_byte);
71DECLARE_LOAD_FUNC(sk_load_byte_msh);
72
73#ifdef CONFIG_PPC64
74#define FUNCTION_DESCR_SIZE 24
75#else
76#define FUNCTION_DESCR_SIZE 0
77#endif
78
79/*
80 * 16-bit immediate helper macros: HA() is for use with sign-extending instrs
81 * (e.g. LD, ADDI). If the bottom 16 bits is "-ve", add another bit into the
82 * top half to negate the effect (i.e. 0xffff + 1 = 0x(1)0000).
83 */
84#define IMM_H(i) ((uintptr_t)(i)>>16)
85#define IMM_HA(i) (((uintptr_t)(i)>>16) + \
86 (((uintptr_t)(i) & 0x8000) >> 15))
87#define IMM_L(i) ((uintptr_t)(i) & 0xffff)
88
89#define PLANT_INSTR(d, idx, instr) \
90 do { if (d) { (d)[idx] = instr; } idx++; } while (0)
91#define EMIT(instr) PLANT_INSTR(image, ctx->idx, instr)
92
93#define PPC_NOP() EMIT(PPC_INST_NOP)
94#define PPC_BLR() EMIT(PPC_INST_BLR)
95#define PPC_BLRL() EMIT(PPC_INST_BLRL)
96#define PPC_MTLR(r) EMIT(PPC_INST_MTLR | ___PPC_RT(r))
97#define PPC_ADDI(d, a, i) EMIT(PPC_INST_ADDI | ___PPC_RT(d) | \
98 ___PPC_RA(a) | IMM_L(i))
99#define PPC_MR(d, a) PPC_OR(d, a, a)
100#define PPC_LI(r, i) PPC_ADDI(r, 0, i)
101#define PPC_ADDIS(d, a, i) EMIT(PPC_INST_ADDIS | \
102 ___PPC_RS(d) | ___PPC_RA(a) | IMM_L(i))
103#define PPC_LIS(r, i) PPC_ADDIS(r, 0, i)
104#define PPC_STD(r, base, i) EMIT(PPC_INST_STD | ___PPC_RS(r) | \
105 ___PPC_RA(base) | ((i) & 0xfffc))
106#define PPC_STDU(r, base, i) EMIT(PPC_INST_STDU | ___PPC_RS(r) | \
107 ___PPC_RA(base) | ((i) & 0xfffc))
108#define PPC_STW(r, base, i) EMIT(PPC_INST_STW | ___PPC_RS(r) | \
109 ___PPC_RA(base) | ((i) & 0xfffc))
110#define PPC_STWU(r, base, i) EMIT(PPC_INST_STWU | ___PPC_RS(r) | \
111 ___PPC_RA(base) | ((i) & 0xfffc))
112
113#define PPC_LBZ(r, base, i) EMIT(PPC_INST_LBZ | ___PPC_RT(r) | \
114 ___PPC_RA(base) | IMM_L(i))
115#define PPC_LD(r, base, i) EMIT(PPC_INST_LD | ___PPC_RT(r) | \
116 ___PPC_RA(base) | IMM_L(i))
117#define PPC_LWZ(r, base, i) EMIT(PPC_INST_LWZ | ___PPC_RT(r) | \
118 ___PPC_RA(base) | IMM_L(i))
119#define PPC_LHZ(r, base, i) EMIT(PPC_INST_LHZ | ___PPC_RT(r) | \
120 ___PPC_RA(base) | IMM_L(i))
121#define PPC_LHBRX(r, base, b) EMIT(PPC_INST_LHBRX | ___PPC_RT(r) | \
122 ___PPC_RA(base) | ___PPC_RB(b))
123
124#ifdef CONFIG_PPC64
125#define PPC_BPF_LL(r, base, i) do { PPC_LD(r, base, i); } while(0)
126#define PPC_BPF_STL(r, base, i) do { PPC_STD(r, base, i); } while(0)
127#define PPC_BPF_STLU(r, base, i) do { PPC_STDU(r, base, i); } while(0)
128#else
129#define PPC_BPF_LL(r, base, i) do { PPC_LWZ(r, base, i); } while(0)
130#define PPC_BPF_STL(r, base, i) do { PPC_STW(r, base, i); } while(0)
131#define PPC_BPF_STLU(r, base, i) do { PPC_STWU(r, base, i); } while(0)
132#endif
133
134/* Convenience helpers for the above with 'far' offsets: */
135#define PPC_LBZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LBZ(r, base, i); \
136 else { PPC_ADDIS(r, base, IMM_HA(i)); \
137 PPC_LBZ(r, r, IMM_L(i)); } } while(0)
138
139#define PPC_LD_OFFS(r, base, i) do { if ((i) < 32768) PPC_LD(r, base, i); \
140 else { PPC_ADDIS(r, base, IMM_HA(i)); \
141 PPC_LD(r, r, IMM_L(i)); } } while(0)
142
143#define PPC_LWZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LWZ(r, base, i); \
144 else { PPC_ADDIS(r, base, IMM_HA(i)); \
145 PPC_LWZ(r, r, IMM_L(i)); } } while(0)
146
147#define PPC_LHZ_OFFS(r, base, i) do { if ((i) < 32768) PPC_LHZ(r, base, i); \
148 else { PPC_ADDIS(r, base, IMM_HA(i)); \
149 PPC_LHZ(r, r, IMM_L(i)); } } while(0)
150
151#ifdef CONFIG_PPC64
152#define PPC_LL_OFFS(r, base, i) do { PPC_LD_OFFS(r, base, i); } while(0)
153#else
154#define PPC_LL_OFFS(r, base, i) do { PPC_LWZ_OFFS(r, base, i); } while(0)
155#endif
156
157#ifdef CONFIG_SMP
158#ifdef CONFIG_PPC64
159#define PPC_BPF_LOAD_CPU(r) \
160 do { BUILD_BUG_ON(FIELD_SIZEOF(struct paca_struct, paca_index) != 2); \
161 PPC_LHZ_OFFS(r, 13, offsetof(struct paca_struct, paca_index)); \
162 } while (0)
163#else
164#define PPC_BPF_LOAD_CPU(r) \
165 do { BUILD_BUG_ON(FIELD_SIZEOF(struct thread_info, cpu) != 4); \
166 PPC_LHZ_OFFS(r, (1 & ~(THREAD_SIZE - 1)), \
167 offsetof(struct thread_info, cpu)); \
168 } while(0)
169#endif
170#else
171#define PPC_BPF_LOAD_CPU(r) do { PPC_LI(r, 0); } while(0)
172#endif
173
174#define PPC_CMPWI(a, i) EMIT(PPC_INST_CMPWI | ___PPC_RA(a) | IMM_L(i))
175#define PPC_CMPDI(a, i) EMIT(PPC_INST_CMPDI | ___PPC_RA(a) | IMM_L(i))
176#define PPC_CMPLWI(a, i) EMIT(PPC_INST_CMPLWI | ___PPC_RA(a) | IMM_L(i))
177#define PPC_CMPLW(a, b) EMIT(PPC_INST_CMPLW | ___PPC_RA(a) | ___PPC_RB(b))
178
179#define PPC_SUB(d, a, b) EMIT(PPC_INST_SUB | ___PPC_RT(d) | \
180 ___PPC_RB(a) | ___PPC_RA(b))
181#define PPC_ADD(d, a, b) EMIT(PPC_INST_ADD | ___PPC_RT(d) | \
182 ___PPC_RA(a) | ___PPC_RB(b))
183#define PPC_MUL(d, a, b) EMIT(PPC_INST_MULLW | ___PPC_RT(d) | \
184 ___PPC_RA(a) | ___PPC_RB(b))
185#define PPC_MULHWU(d, a, b) EMIT(PPC_INST_MULHWU | ___PPC_RT(d) | \
186 ___PPC_RA(a) | ___PPC_RB(b))
187#define PPC_MULI(d, a, i) EMIT(PPC_INST_MULLI | ___PPC_RT(d) | \
188 ___PPC_RA(a) | IMM_L(i))
189#define PPC_DIVWU(d, a, b) EMIT(PPC_INST_DIVWU | ___PPC_RT(d) | \
190 ___PPC_RA(a) | ___PPC_RB(b))
191#define PPC_AND(d, a, b) EMIT(PPC_INST_AND | ___PPC_RA(d) | \
192 ___PPC_RS(a) | ___PPC_RB(b))
193#define PPC_ANDI(d, a, i) EMIT(PPC_INST_ANDI | ___PPC_RA(d) | \
194 ___PPC_RS(a) | IMM_L(i))
195#define PPC_AND_DOT(d, a, b) EMIT(PPC_INST_ANDDOT | ___PPC_RA(d) | \
196 ___PPC_RS(a) | ___PPC_RB(b))
197#define PPC_OR(d, a, b) EMIT(PPC_INST_OR | ___PPC_RA(d) | \
198 ___PPC_RS(a) | ___PPC_RB(b))
199#define PPC_ORI(d, a, i) EMIT(PPC_INST_ORI | ___PPC_RA(d) | \
200 ___PPC_RS(a) | IMM_L(i))
201#define PPC_ORIS(d, a, i) EMIT(PPC_INST_ORIS | ___PPC_RA(d) | \
202 ___PPC_RS(a) | IMM_L(i))
203#define PPC_XOR(d, a, b) EMIT(PPC_INST_XOR | ___PPC_RA(d) | \
204 ___PPC_RS(a) | ___PPC_RB(b))
205#define PPC_XORI(d, a, i) EMIT(PPC_INST_XORI | ___PPC_RA(d) | \
206 ___PPC_RS(a) | IMM_L(i))
207#define PPC_XORIS(d, a, i) EMIT(PPC_INST_XORIS | ___PPC_RA(d) | \
208 ___PPC_RS(a) | IMM_L(i))
209#define PPC_SLW(d, a, s) EMIT(PPC_INST_SLW | ___PPC_RA(d) | \
210 ___PPC_RS(a) | ___PPC_RB(s))
211#define PPC_SRW(d, a, s) EMIT(PPC_INST_SRW | ___PPC_RA(d) | \
212 ___PPC_RS(a) | ___PPC_RB(s))
213/* slwi = rlwinm Rx, Ry, n, 0, 31-n */
214#define PPC_SLWI(d, a, i) EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
215 ___PPC_RS(a) | __PPC_SH(i) | \
216 __PPC_MB(0) | __PPC_ME(31-(i)))
217/* srwi = rlwinm Rx, Ry, 32-n, n, 31 */
218#define PPC_SRWI(d, a, i) EMIT(PPC_INST_RLWINM | ___PPC_RA(d) | \
219 ___PPC_RS(a) | __PPC_SH(32-(i)) | \
220 __PPC_MB(i) | __PPC_ME(31))
221/* sldi = rldicr Rx, Ry, n, 63-n */
222#define PPC_SLDI(d, a, i) EMIT(PPC_INST_RLDICR | ___PPC_RA(d) | \
223 ___PPC_RS(a) | __PPC_SH(i) | \
224 __PPC_MB(63-(i)) | (((i) & 0x20) >> 4))
225#define PPC_NEG(d, a) EMIT(PPC_INST_NEG | ___PPC_RT(d) | ___PPC_RA(a))
226
227/* Long jump; (unconditional 'branch') */
228#define PPC_JMP(dest) EMIT(PPC_INST_BRANCH | \
229 (((dest) - (ctx->idx * 4)) & 0x03fffffc))
230/* "cond" here covers BO:BI fields. */
231#define PPC_BCC_SHORT(cond, dest) EMIT(PPC_INST_BRANCH_COND | \
232 (((cond) & 0x3ff) << 16) | \
233 (((dest) - (ctx->idx * 4)) & \
234 0xfffc))
235#define PPC_LI32(d, i) do { PPC_LI(d, IMM_L(i)); \
236 if ((u32)(uintptr_t)(i) >= 32768) { \
237 PPC_ADDIS(d, d, IMM_HA(i)); \
238 } } while(0)
239#define PPC_LI64(d, i) do { \
240 if (!((uintptr_t)(i) & 0xffffffff00000000ULL)) \
241 PPC_LI32(d, i); \
242 else { \
243 PPC_LIS(d, ((uintptr_t)(i) >> 48)); \
244 if ((uintptr_t)(i) & 0x0000ffff00000000ULL) \
245 PPC_ORI(d, d, \
246 ((uintptr_t)(i) >> 32) & 0xffff); \
247 PPC_SLDI(d, d, 32); \
248 if ((uintptr_t)(i) & 0x00000000ffff0000ULL) \
249 PPC_ORIS(d, d, \
250 ((uintptr_t)(i) >> 16) & 0xffff); \
251 if ((uintptr_t)(i) & 0x000000000000ffffULL) \
252 PPC_ORI(d, d, (uintptr_t)(i) & 0xffff); \
253 } } while (0);
254
255#ifdef CONFIG_PPC64
256#define PPC_FUNC_ADDR(d,i) do { PPC_LI64(d, i); } while(0)
257#else
258#define PPC_FUNC_ADDR(d,i) do { PPC_LI32(d, i); } while(0)
259#endif
260
261#define PPC_LHBRX_OFFS(r, base, i) \
262 do { PPC_LI32(r, i); PPC_LHBRX(r, r, base); } while(0)
263#ifdef __LITTLE_ENDIAN__
264#define PPC_NTOHS_OFFS(r, base, i) PPC_LHBRX_OFFS(r, base, i)
265#else
266#define PPC_NTOHS_OFFS(r, base, i) PPC_LHZ_OFFS(r, base, i)
267#endif
268
269static inline bool is_nearbranch(int offset)
270{
271 return (offset < 32768) && (offset >= -32768);
272}
273
274/*
275 * The fly in the ointment of code size changing from pass to pass is
276 * avoided by padding the short branch case with a NOP. If code size differs
277 * with different branch reaches we will have the issue of code moving from
278 * one pass to the next and will need a few passes to converge on a stable
279 * state.
280 */
281#define PPC_BCC(cond, dest) do { \
282 if (is_nearbranch((dest) - (ctx->idx * 4))) { \
283 PPC_BCC_SHORT(cond, dest); \
284 PPC_NOP(); \
285 } else { \
286 /* Flip the 'T or F' bit to invert comparison */ \
287 PPC_BCC_SHORT(cond ^ COND_CMP_TRUE, (ctx->idx+2)*4); \
288 PPC_JMP(dest); \
289 } } while(0)
290
291/* To create a branch condition, select a bit of cr0... */
292#define CR0_LT 0
293#define CR0_GT 1
294#define CR0_EQ 2
295/* ...and modify BO[3] */
296#define COND_CMP_TRUE 0x100
297#define COND_CMP_FALSE 0x000
298/* Together, they make all required comparisons: */
299#define COND_GT (CR0_GT | COND_CMP_TRUE)
300#define COND_GE (CR0_LT | COND_CMP_FALSE)
301#define COND_EQ (CR0_EQ | COND_CMP_TRUE)
302#define COND_NE (CR0_EQ | COND_CMP_FALSE)
303#define COND_LT (CR0_LT | COND_CMP_TRUE)
304
305#define SEEN_DATAREF 0x10000 /* might call external helpers */
306#define SEEN_XREG 0x20000 /* X reg is used */
307#define SEEN_MEM 0x40000 /* SEEN_MEM+(1<<n) = use mem[n] for temporary
308 * storage */
309#define SEEN_MEM_MSK 0x0ffff
310
311struct codegen_context {
312 unsigned int seen;
313 unsigned int idx;
314 int pc_ret0; /* bpf index of first RET #0 instruction (if any) */
315};
316
317#endif
318
319#endif