[pcsx_rearmed.git] / deps / lightrec / regcache.c

// SPDX-License-Identifier: LGPL-2.1-or-later
/*
 * Copyright (C) 2014-2021 Paul Cercueil <paul@crapouillou.net>
 */

#include "debug.h"
#include "memmanager.h"
#include "lightning-wrapper.h"
#include "regcache.h"

#include <stdbool.h>
#include <stddef.h>

struct native_register {
	bool used, loaded, dirty, output, extend, extended,
	     zero_extend, zero_extended, locked;
	s8 emulated_register;
};

struct regcache {
	struct lightrec_state *state;
	struct native_register lightrec_regs[NUM_REGS + NUM_TEMPS];
};

static const char * mips_regs[] = {
	"zero",
	"at",
	"v0", "v1",
	"a0", "a1", "a2", "a3",
	"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7",
	"s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
	"t8", "t9",
	"k0", "k1",
	"gp", "sp", "fp", "ra",
	"lo", "hi",
};

const char * lightrec_reg_name(u8 reg)
{
	return mips_regs[reg];
}

static inline bool lightrec_reg_is_zero(u8 jit_reg)
{
#if defined(__mips__) || defined(__alpha__) || defined(__riscv)
	if (jit_reg == _ZERO)
		return true;
#endif
	return false;
}

static inline s8 lightrec_get_hardwired_reg(u8 reg)
{
#if defined(__mips__) || defined(__alpha__) || defined(__riscv)
	if (reg == 0)
		return _ZERO;
#endif
	return -1;
}

static inline u8 lightrec_reg_number(const struct regcache *cache,
		const struct native_register *nreg)
{
	return (u8) (((uintptr_t) nreg - (uintptr_t) cache->lightrec_regs)
			/ sizeof(*nreg));
}

static inline u8 lightrec_reg_to_lightning(const struct regcache *cache,
		const struct native_register *nreg)
{
	u8 offset = lightrec_reg_number(cache, nreg);
	return offset < NUM_REGS ? JIT_V(offset) : JIT_R(offset - NUM_REGS);
}

static inline struct native_register * lightning_reg_to_lightrec(
		struct regcache *cache, u8 reg)
{
	if ((JIT_V0 > JIT_R0 && reg >= JIT_V0) ||
			(JIT_V0 < JIT_R0 && reg < JIT_R0)) {
		if (JIT_V1 > JIT_V0)
			return &cache->lightrec_regs[reg - JIT_V0];
		else
			return &cache->lightrec_regs[JIT_V0 - reg];
	} else {
		if (JIT_R1 > JIT_R0)
			return &cache->lightrec_regs[NUM_REGS + reg - JIT_R0];
		else
			return &cache->lightrec_regs[NUM_REGS + JIT_R0 - reg];
	}
}

u8 lightrec_get_reg_in_flags(struct regcache *cache, u8 jit_reg)
{
	struct native_register *reg;
	u8 flags = 0;

	if (lightrec_reg_is_zero(jit_reg))
		return REG_EXT | REG_ZEXT;

	reg = lightning_reg_to_lightrec(cache, jit_reg);
	if (reg->extended)
		flags |= REG_EXT;
	if (reg->zero_extended)
		flags |= REG_ZEXT;

	return flags;
}

void lightrec_set_reg_out_flags(struct regcache *cache, u8 jit_reg, u8 flags)
{
	struct native_register *reg;

	if (!lightrec_reg_is_zero(jit_reg)) {
		reg = lightning_reg_to_lightrec(cache, jit_reg);
		reg->extend = flags & REG_EXT;
		reg->zero_extend = flags & REG_ZEXT;
	}
}

static struct native_register * alloc_temp(struct regcache *cache)
{
	unsigned int i;

	/* We search the register list in reverse order. As temporaries are
	 * meant to be used only in the emitter functions, they can be mapped to
	 * caller-saved registers, as they won't have to be saved back to
	 * memory. */
	for (i = ARRAY_SIZE(cache->lightrec_regs); i; i--) {
		struct native_register *nreg = &cache->lightrec_regs[i - 1];
		if (!nreg->used && !nreg->loaded && !nreg->dirty)
			return nreg;
	}

	for (i = ARRAY_SIZE(cache->lightrec_regs); i; i--) {
		struct native_register *nreg = &cache->lightrec_regs[i - 1];
		if (!nreg->used)
			return nreg;
	}

	return NULL;
}

static struct native_register * find_mapped_reg(struct regcache *cache,
						u8 reg, bool out)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
		struct native_register *nreg = &cache->lightrec_regs[i];
		if ((!reg || nreg->loaded || nreg->dirty) &&
				nreg->emulated_register == reg &&
				(!out || !nreg->locked))
			return nreg;
	}

	return NULL;
}

static struct native_register * alloc_in_out(struct regcache *cache,
					     u8 reg, bool out)
{
	struct native_register *nreg;
	unsigned int i;

	/* Try to find if the register is already mapped somewhere */
	nreg = find_mapped_reg(cache, reg, out);
	if (nreg)
		return nreg;

	/* Try to allocate a non-dirty, non-loaded register.
	 * Loaded registers may be re-used later, so it's better to avoid
	 * re-using one if possible. */
	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
		nreg = &cache->lightrec_regs[i];
		if (!nreg->used && !nreg->dirty && !nreg->loaded)
			return nreg;
	}

	/* Try to allocate a non-dirty register */
	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
		nreg = &cache->lightrec_regs[i];
		if (!nreg->used && !nreg->dirty)
			return nreg;
	}

	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
		nreg = &cache->lightrec_regs[i];
		if (!nreg->used)
			return nreg;
	}

	return NULL;
}

static void lightrec_discard_nreg(struct native_register *nreg)
{
	nreg->extended = false;
	nreg->zero_extended = false;
	nreg->loaded = false;
	nreg->output = false;
	nreg->dirty = false;
	nreg->used = false;
	nreg->locked = false;
	nreg->emulated_register = -1;
}

static void lightrec_unload_nreg(struct regcache *cache, jit_state_t *_jit,
		struct native_register *nreg, u8 jit_reg)
{
	/* If we get a dirty register, store back the old value */
	if (nreg->dirty) {
		s16 offset = offsetof(struct lightrec_state, regs.gpr)
			+ (nreg->emulated_register << 2);

		jit_stxi_i(offset, LIGHTREC_REG_STATE, jit_reg);
	}

	lightrec_discard_nreg(nreg);
}

void lightrec_unload_reg(struct regcache *cache, jit_state_t *_jit, u8 jit_reg)
{
	if (lightrec_reg_is_zero(jit_reg))
		return;

	lightrec_unload_nreg(cache, _jit,
			lightning_reg_to_lightrec(cache, jit_reg), jit_reg);
}

/* lightrec_lock_reg: the register will be cleaned if dirty, then locked.
 * A locked register cannot only be used as input, not output. */
void lightrec_lock_reg(struct regcache *cache, jit_state_t *_jit, u8 jit_reg)
{
	struct native_register *reg;

	if (lightrec_reg_is_zero(jit_reg))
		return;

	reg = lightning_reg_to_lightrec(cache, jit_reg);
	lightrec_clean_reg(cache, _jit, jit_reg);

	reg->locked = true;
}

u8 lightrec_alloc_reg(struct regcache *cache, jit_state_t *_jit, u8 jit_reg)
{
	struct native_register *reg;

	if (lightrec_reg_is_zero(jit_reg))
		return jit_reg;

	reg = lightning_reg_to_lightrec(cache, jit_reg);
	lightrec_unload_nreg(cache, _jit, reg, jit_reg);

	reg->used = true;
	return jit_reg;
}

u8 lightrec_alloc_reg_temp(struct regcache *cache, jit_state_t *_jit)
{
	u8 jit_reg;
	struct native_register *nreg = alloc_temp(cache);
	if (!nreg) {
		/* No free register, no dirty register to free. */
		pr_err("No more registers! Abandon ship!\n");
		return 0;
	}

	jit_reg = lightrec_reg_to_lightning(cache, nreg);
	lightrec_unload_nreg(cache, _jit, nreg, jit_reg);

	nreg->used = true;
	return jit_reg;
}

u8 lightrec_alloc_reg_out(struct regcache *cache, jit_state_t *_jit,
			  u8 reg, u8 flags)
{
	struct native_register *nreg;
	u8 jit_reg;
	s8 hw_reg;

	hw_reg = lightrec_get_hardwired_reg(reg);
	if (hw_reg >= 0)
		return (u8) hw_reg;

	nreg = alloc_in_out(cache, reg, true);
	if (!nreg) {
		/* No free register, no dirty register to free. */
		pr_err("No more registers! Abandon ship!\n");
		return 0;
	}

	jit_reg = lightrec_reg_to_lightning(cache, nreg);

	/* If we get a dirty register that doesn't correspond to the one
	 * we're requesting, store back the old value */
	if (nreg->emulated_register != reg)
		lightrec_unload_nreg(cache, _jit, nreg, jit_reg);

	nreg->used = true;
	nreg->output = true;
	nreg->emulated_register = reg;
	nreg->extend = flags & REG_EXT;
	nreg->zero_extend = flags & REG_ZEXT;
	return jit_reg;
}

u8 lightrec_alloc_reg_in(struct regcache *cache, jit_state_t *_jit,
			 u8 reg, u8 flags)
{
	struct native_register *nreg;
	u8 jit_reg;
	bool reg_changed;
	s8 hw_reg;

	hw_reg = lightrec_get_hardwired_reg(reg);
	if (hw_reg >= 0)
		return (u8) hw_reg;

	nreg = alloc_in_out(cache, reg, false);
	if (!nreg) {
		/* No free register, no dirty register to free. */
		pr_err("No more registers! Abandon ship!\n");
		return 0;
	}

	jit_reg = lightrec_reg_to_lightning(cache, nreg);

	/* If we get a dirty register that doesn't correspond to the one
	 * we're requesting, store back the old value */
	reg_changed = nreg->emulated_register != reg;
	if (reg_changed)
		lightrec_unload_nreg(cache, _jit, nreg, jit_reg);

	if (!nreg->loaded && !nreg->dirty && reg != 0) {
		s16 offset = offsetof(struct lightrec_state, regs.gpr)
			+ (reg << 2);

		nreg->zero_extended = flags & REG_ZEXT;
		nreg->extended = !nreg->zero_extended;

		/* Load previous value from register cache */
		if (nreg->zero_extended)
			jit_ldxi_ui(jit_reg, LIGHTREC_REG_STATE, offset);
		else
			jit_ldxi_i(jit_reg, LIGHTREC_REG_STATE, offset);

		nreg->loaded = true;
	}

	/* Clear register r0 before use */
	if (reg == 0 && (!nreg->loaded || nreg->dirty)) {
		jit_movi(jit_reg, 0);
		nreg->extended = true;
		nreg->zero_extended = true;
		nreg->loaded = true;
	}

	nreg->used = true;
	nreg->output = false;
	nreg->emulated_register = reg;

	if ((flags & REG_EXT) && !nreg->extended &&
	    (!nreg->zero_extended || !(flags & REG_ZEXT))) {
		nreg->extended = true;
		nreg->zero_extended = false;
		jit_extr_i(jit_reg, jit_reg);
	} else if (!(flags & REG_EXT) && (flags & REG_ZEXT) &&
		   !nreg->zero_extended) {
		nreg->zero_extended = true;
		nreg->extended = false;
		jit_extr_ui(jit_reg, jit_reg);
	}

	return jit_reg;
}

u8 lightrec_request_reg_in(struct regcache *cache, jit_state_t *_jit,
			   u8 reg, u8 jit_reg)
{
	struct native_register *nreg;
	u16 offset;

	nreg = find_mapped_reg(cache, reg, false);
	if (nreg) {
		jit_reg = lightrec_reg_to_lightning(cache, nreg);
		nreg->used = true;
		return jit_reg;
	}

	nreg = lightning_reg_to_lightrec(cache, jit_reg);
	lightrec_unload_nreg(cache, _jit, nreg, jit_reg);

	/* Load previous value from register cache */
	offset = offsetof(struct lightrec_state, regs.gpr) + (reg << 2);
	jit_ldxi_i(jit_reg, LIGHTREC_REG_STATE, offset);

	nreg->extended = true;
	nreg->zero_extended = false;
	nreg->used = true;
	nreg->loaded = true;
	nreg->emulated_register = reg;

	return jit_reg;
}

static void free_reg(struct native_register *nreg)
{
	/* Set output registers as dirty */
	if (nreg->used && nreg->output && nreg->emulated_register > 0)
		nreg->dirty = true;
	if (nreg->output) {
		nreg->extended = nreg->extend;
		nreg->zero_extended = nreg->zero_extend;
	}
	nreg->used = false;
}

void lightrec_free_reg(struct regcache *cache, u8 jit_reg)
{
	if (!lightrec_reg_is_zero(jit_reg))
		free_reg(lightning_reg_to_lightrec(cache, jit_reg));
}

void lightrec_free_regs(struct regcache *cache)
{
	unsigned int i;

	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++)
		free_reg(&cache->lightrec_regs[i]);
}

static void clean_reg(jit_state_t *_jit,
		struct native_register *nreg, u8 jit_reg, bool clean)
{
	if (nreg->dirty) {
		s16 offset = offsetof(struct lightrec_state, regs.gpr)
			+ (nreg->emulated_register << 2);

		jit_stxi_i(offset, LIGHTREC_REG_STATE, jit_reg);
		nreg->loaded |= nreg->dirty;
		nreg->dirty ^= clean;
	}
}

static void clean_regs(struct regcache *cache, jit_state_t *_jit, bool clean)
{
	unsigned int i;

	for (i = 0; i < NUM_REGS; i++)
		clean_reg(_jit, &cache->lightrec_regs[i], JIT_V(i), clean);
	for (i = 0; i < NUM_TEMPS; i++) {
		clean_reg(_jit, &cache->lightrec_regs[i + NUM_REGS],
				JIT_R(i), clean);
	}
}

void lightrec_storeback_regs(struct regcache *cache, jit_state_t *_jit)
{
	clean_regs(cache, _jit, false);
}

void lightrec_clean_regs(struct regcache *cache, jit_state_t *_jit)
{
	clean_regs(cache, _jit, true);
}

void lightrec_clean_reg(struct regcache *cache, jit_state_t *_jit, u8 jit_reg)
{
	struct native_register *reg;

	if (!lightrec_reg_is_zero(jit_reg)) {
		reg = lightning_reg_to_lightrec(cache, jit_reg);
		clean_reg(_jit, reg, jit_reg, true);
	}
}

void lightrec_clean_reg_if_loaded(struct regcache *cache, jit_state_t *_jit,
				  u8 reg, bool unload)
{
	struct native_register *nreg;
	u8 jit_reg;

	nreg = find_mapped_reg(cache, reg, false);
	if (nreg) {
		jit_reg = lightrec_reg_to_lightning(cache, nreg);

		if (unload)
			lightrec_unload_nreg(cache, _jit, nreg, jit_reg);
		else
			clean_reg(_jit, nreg, jit_reg, true);
	}
}

void lightrec_discard_reg_if_loaded(struct regcache *cache, u8 reg)
{
	struct native_register *nreg;

	nreg = find_mapped_reg(cache, reg, false);
	if (nreg)
		lightrec_discard_nreg(nreg);
}

struct native_register * lightrec_regcache_enter_branch(struct regcache *cache)
{
	struct native_register *backup;

	backup = lightrec_malloc(cache->state, MEM_FOR_LIGHTREC,
				 sizeof(cache->lightrec_regs));
	memcpy(backup, &cache->lightrec_regs, sizeof(cache->lightrec_regs));

	return backup;
}

void lightrec_regcache_leave_branch(struct regcache *cache,
			struct native_register *regs)
{
	memcpy(&cache->lightrec_regs, regs, sizeof(cache->lightrec_regs));
	lightrec_free(cache->state, MEM_FOR_LIGHTREC,
		      sizeof(cache->lightrec_regs), regs);
}

void lightrec_regcache_reset(struct regcache *cache)
{
	memset(&cache->lightrec_regs, 0, sizeof(cache->lightrec_regs));
}

struct regcache * lightrec_regcache_init(struct lightrec_state *state)
{
	struct regcache *cache;

	cache = lightrec_calloc(state, MEM_FOR_LIGHTREC, sizeof(*cache));
	if (!cache)
		return NULL;

	cache->state = state;

	return cache;
}

void lightrec_free_regcache(struct regcache *cache)
{
	return lightrec_free(cache->state, MEM_FOR_LIGHTREC,
			     sizeof(*cache), cache);
}

void lightrec_regcache_mark_live(struct regcache *cache, jit_state_t *_jit)
{
	struct native_register *nreg;
	unsigned int i;

#ifdef _WIN32
	/* FIXME: GNU Lightning on Windows seems to use our mapped registers as
	 * temporaries. Until the actual bug is found and fixed, unconditionally
	 * mark our registers as live here. */
	for (i = 0; i < NUM_REGS; i++) {
		nreg = &cache->lightrec_regs[i];

		if (nreg->used || nreg->loaded || nreg->dirty)
			jit_live(JIT_V(i));
	}
#endif

	for (i = 0; i < NUM_TEMPS; i++) {
		nreg = &cache->lightrec_regs[NUM_REGS + i];

		if (nreg->used || nreg->loaded || nreg->dirty)
			jit_live(JIT_R(i));
	}
}
Commit	Line	Data
98fa08a5	1	// SPDX-License-Identifier: LGPL-2.1-or-later
d16005f8	2	/*
98fa08a5	3	* Copyright (C) 2014-2021 Paul Cercueil <paul@crapouillou.net>
d16005f8 PC	4	*/
	5
	6	#include "debug.h"
	7	#include "memmanager.h"
98fa08a5	8	#include "lightning-wrapper.h"
d16005f8 PC	9	#include "regcache.h"
d16005f8 PC	10
d16005f8 PC	11	#include <stdbool.h>
	12	#include <stddef.h>
	13
	14	struct native_register {
98fa08a5 PC	15	bool used, loaded, dirty, output, extend, extended,
98fa08a5 PC	16	zero_extend, zero_extended, locked;
d16005f8 PC	17	s8 emulated_register;
	18	};
	19
	20	struct regcache {
	21	struct lightrec_state *state;
	22	struct native_register lightrec_regs[NUM_REGS + NUM_TEMPS];
	23	};
	24
	25	static const char * mips_regs[] = {
	26	"zero",
	27	"at",
	28	"v0", "v1",
	29	"a0", "a1", "a2", "a3",
	30	"t0", "t1", "t2", "t3", "t4", "t5", "t6", "t7",
	31	"s0", "s1", "s2", "s3", "s4", "s5", "s6", "s7",
	32	"t8", "t9",
	33	"k0", "k1",
	34	"gp", "sp", "fp", "ra",
	35	"lo", "hi",
	36	};
	37
	38	const char * lightrec_reg_name(u8 reg)
	39	{
	40	return mips_regs[reg];
	41	}
	42
98fa08a5 PC	43	static inline bool lightrec_reg_is_zero(u8 jit_reg)
	44	{
	45	#if defined(__mips__) \|\| defined(__alpha__) \|\| defined(__riscv)
	46	if (jit_reg == _ZERO)
	47	return true;
	48	#endif
	49	return false;
	50	}
	51
	52	static inline s8 lightrec_get_hardwired_reg(u8 reg)
	53	{
	54	#if defined(__mips__) \|\| defined(__alpha__) \|\| defined(__riscv)
	55	if (reg == 0)
	56	return _ZERO;
	57	#endif
	58	return -1;
	59	}
	60
d16005f8 PC	61	static inline u8 lightrec_reg_number(const struct regcache *cache,
	62	const struct native_register *nreg)
	63	{
	64	return (u8) (((uintptr_t) nreg - (uintptr_t) cache->lightrec_regs)
	65	/ sizeof(*nreg));
	66	}
	67
	68	static inline u8 lightrec_reg_to_lightning(const struct regcache *cache,
	69	const struct native_register *nreg)
	70	{
	71	u8 offset = lightrec_reg_number(cache, nreg);
	72	return offset < NUM_REGS ? JIT_V(offset) : JIT_R(offset - NUM_REGS);
	73	}
	74
	75	static inline struct native_register * lightning_reg_to_lightrec(
	76	struct regcache *cache, u8 reg)
	77	{
	78	if ((JIT_V0 > JIT_R0 && reg >= JIT_V0) \|\|
	79	(JIT_V0 < JIT_R0 && reg < JIT_R0)) {
	80	if (JIT_V1 > JIT_V0)
	81	return &cache->lightrec_regs[reg - JIT_V0];
	82	else
	83	return &cache->lightrec_regs[JIT_V0 - reg];
	84	} else {
	85	if (JIT_R1 > JIT_R0)
	86	return &cache->lightrec_regs[NUM_REGS + reg - JIT_R0];
	87	else
	88	return &cache->lightrec_regs[NUM_REGS + JIT_R0 - reg];
	89	}
	90	}
	91
98fa08a5 PC	92	u8 lightrec_get_reg_in_flags(struct regcache *cache, u8 jit_reg)
	93	{
	94	struct native_register *reg;
	95	u8 flags = 0;
	96
	97	if (lightrec_reg_is_zero(jit_reg))
	98	return REG_EXT \| REG_ZEXT;
	99
	100	reg = lightning_reg_to_lightrec(cache, jit_reg);
	101	if (reg->extended)
	102	flags \|= REG_EXT;
	103	if (reg->zero_extended)
	104	flags \|= REG_ZEXT;
	105
	106	return flags;
	107	}
	108
	109	void lightrec_set_reg_out_flags(struct regcache *cache, u8 jit_reg, u8 flags)
	110	{
	111	struct native_register *reg;
	112
	113	if (!lightrec_reg_is_zero(jit_reg)) {
	114	reg = lightning_reg_to_lightrec(cache, jit_reg);
	115	reg->extend = flags & REG_EXT;
	116	reg->zero_extend = flags & REG_ZEXT;
	117	}
	118	}
	119
d16005f8 PC	120	static struct native_register * alloc_temp(struct regcache *cache)
	121	{
	122	unsigned int i;
	123
	124	/* We search the register list in reverse order. As temporaries are
	125	* meant to be used only in the emitter functions, they can be mapped to
	126	* caller-saved registers, as they won't have to be saved back to
	127	* memory. */
	128	for (i = ARRAY_SIZE(cache->lightrec_regs); i; i--) {
	129	struct native_register *nreg = &cache->lightrec_regs[i - 1];
	130	if (!nreg->used && !nreg->loaded && !nreg->dirty)
	131	return nreg;
	132	}
	133
	134	for (i = ARRAY_SIZE(cache->lightrec_regs); i; i--) {
	135	struct native_register *nreg = &cache->lightrec_regs[i - 1];
	136	if (!nreg->used)
	137	return nreg;
	138	}
	139
	140	return NULL;
	141	}
	142
	143	static struct native_register * find_mapped_reg(struct regcache *cache,
	144	u8 reg, bool out)
	145	{
	146	unsigned int i;
	147
	148	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
	149	struct native_register *nreg = &cache->lightrec_regs[i];
	150	if ((!reg \|\| nreg->loaded \|\| nreg->dirty) &&
	151	nreg->emulated_register == reg &&
	152	(!out \|\| !nreg->locked))
	153	return nreg;
	154	}
	155
	156	return NULL;
	157	}
	158
	159	static struct native_register * alloc_in_out(struct regcache *cache,
	160	u8 reg, bool out)
	161	{
	162	struct native_register *nreg;
	163	unsigned int i;
	164
	165	/* Try to find if the register is already mapped somewhere */
	166	nreg = find_mapped_reg(cache, reg, out);
	167	if (nreg)
	168	return nreg;
	169
	170	/* Try to allocate a non-dirty, non-loaded register.
	171	* Loaded registers may be re-used later, so it's better to avoid
	172	* re-using one if possible. */
	173	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
	174	nreg = &cache->lightrec_regs[i];
	175	if (!nreg->used && !nreg->dirty && !nreg->loaded)
	176	return nreg;
	177	}
	178
	179	/* Try to allocate a non-dirty register */
	180	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
	181	nreg = &cache->lightrec_regs[i];
	182	if (!nreg->used && !nreg->dirty)
	183	return nreg;
184	}
185
186	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++) {
187	nreg = &cache->lightrec_regs[i];
188	if (!nreg->used)
189	return nreg;
190	}
191
192	return NULL;
193	}
194
195	static void lightrec_discard_nreg(struct native_register *nreg)
196	{
197	nreg->extended = false;
98fa08a5	198	nreg->zero_extended = false;
d16005f8 PC	199	nreg->loaded = false;
	200	nreg->output = false;
	201	nreg->dirty = false;
	202	nreg->used = false;
	203	nreg->locked = false;
	204	nreg->emulated_register = -1;
	205	}
	206
	207	static void lightrec_unload_nreg(struct regcache cache, jit_state_t _jit,
	208	struct native_register *nreg, u8 jit_reg)
	209	{
	210	/* If we get a dirty register, store back the old value */
	211	if (nreg->dirty) {
98fa08a5	212	s16 offset = offsetof(struct lightrec_state, regs.gpr)
d16005f8 PC	213	+ (nreg->emulated_register << 2);
	214
	215	jit_stxi_i(offset, LIGHTREC_REG_STATE, jit_reg);
	216	}
	217
	218	lightrec_discard_nreg(nreg);
	219	}
	220
	221	void lightrec_unload_reg(struct regcache cache, jit_state_t _jit, u8 jit_reg)
	222	{
98fa08a5 PC	223	if (lightrec_reg_is_zero(jit_reg))
	224	return;
	225
d16005f8 PC	226	lightrec_unload_nreg(cache, _jit,
	227	lightning_reg_to_lightrec(cache, jit_reg), jit_reg);
	228	}
	229
	230	/* lightrec_lock_reg: the register will be cleaned if dirty, then locked.
	231	* A locked register cannot only be used as input, not output. */
	232	void lightrec_lock_reg(struct regcache cache, jit_state_t _jit, u8 jit_reg)
	233	{
98fa08a5 PC	234	struct native_register *reg;
	235
	236	if (lightrec_reg_is_zero(jit_reg))
	237	return;
d16005f8	238
98fa08a5	239	reg = lightning_reg_to_lightrec(cache, jit_reg);
d16005f8 PC	240	lightrec_clean_reg(cache, _jit, jit_reg);
	241
	242	reg->locked = true;
	243	}
	244
	245	u8 lightrec_alloc_reg(struct regcache cache, jit_state_t _jit, u8 jit_reg)
	246	{
98fa08a5	247	struct native_register *reg;
d16005f8	248
98fa08a5 PC	249	if (lightrec_reg_is_zero(jit_reg))
	250	return jit_reg;
	251
	252	reg = lightning_reg_to_lightrec(cache, jit_reg);
d16005f8 PC	253	lightrec_unload_nreg(cache, _jit, reg, jit_reg);
	254
	255	reg->used = true;
	256	return jit_reg;
	257	}
	258
	259	u8 lightrec_alloc_reg_temp(struct regcache cache, jit_state_t _jit)
	260	{
	261	u8 jit_reg;
	262	struct native_register *nreg = alloc_temp(cache);
	263	if (!nreg) {
	264	/* No free register, no dirty register to free. */
	265	pr_err("No more registers! Abandon ship!\n");
	266	return 0;
	267	}
	268
	269	jit_reg = lightrec_reg_to_lightning(cache, nreg);
	270	lightrec_unload_nreg(cache, _jit, nreg, jit_reg);
	271
	272	nreg->used = true;
	273	return jit_reg;
	274	}
	275
98fa08a5 PC	276	u8 lightrec_alloc_reg_out(struct regcache cache, jit_state_t _jit,
98fa08a5 PC	277	u8 reg, u8 flags)
d16005f8	278	{
98fa08a5	279	struct native_register *nreg;
d16005f8	280	u8 jit_reg;
98fa08a5 PC	281	s8 hw_reg;
	282
	283	hw_reg = lightrec_get_hardwired_reg(reg);
	284	if (hw_reg >= 0)
	285	return (u8) hw_reg;
	286
	287	nreg = alloc_in_out(cache, reg, true);
d16005f8 PC	288	if (!nreg) {
	289	/* No free register, no dirty register to free. */
	290	pr_err("No more registers! Abandon ship!\n");
	291	return 0;
	292	}
	293
	294	jit_reg = lightrec_reg_to_lightning(cache, nreg);
	295
	296	/* If we get a dirty register that doesn't correspond to the one
	297	* we're requesting, store back the old value */
	298	if (nreg->emulated_register != reg)
	299	lightrec_unload_nreg(cache, _jit, nreg, jit_reg);
	300
d16005f8 PC	301	nreg->used = true;
	302	nreg->output = true;
	303	nreg->emulated_register = reg;
98fa08a5 PC	304	nreg->extend = flags & REG_EXT;
98fa08a5 PC	305	nreg->zero_extend = flags & REG_ZEXT;
d16005f8 PC	306	return jit_reg;
	307	}
	308
98fa08a5 PC	309	u8 lightrec_alloc_reg_in(struct regcache cache, jit_state_t _jit,
98fa08a5 PC	310	u8 reg, u8 flags)
d16005f8	311	{
98fa08a5	312	struct native_register *nreg;
d16005f8 PC	313	u8 jit_reg;
d16005f8 PC	314	bool reg_changed;
98fa08a5 PC	315	s8 hw_reg;
	316
	317	hw_reg = lightrec_get_hardwired_reg(reg);
	318	if (hw_reg >= 0)
	319	return (u8) hw_reg;
	320
	321	nreg = alloc_in_out(cache, reg, false);
d16005f8 PC	322	if (!nreg) {
	323	/* No free register, no dirty register to free. */
	324	pr_err("No more registers! Abandon ship!\n");
	325	return 0;
	326	}
	327
	328	jit_reg = lightrec_reg_to_lightning(cache, nreg);
	329
	330	/* If we get a dirty register that doesn't correspond to the one
	331	* we're requesting, store back the old value */
	332	reg_changed = nreg->emulated_register != reg;
	333	if (reg_changed)
	334	lightrec_unload_nreg(cache, _jit, nreg, jit_reg);
	335
	336	if (!nreg->loaded && !nreg->dirty && reg != 0) {
98fa08a5	337	s16 offset = offsetof(struct lightrec_state, regs.gpr)
d16005f8 PC	338	+ (reg << 2);
d16005f8 PC	339
98fa08a5 PC	340	nreg->zero_extended = flags & REG_ZEXT;
	341	nreg->extended = !nreg->zero_extended;
	342
d16005f8	343	/* Load previous value from register cache */
98fa08a5 PC	344	if (nreg->zero_extended)
	345	jit_ldxi_ui(jit_reg, LIGHTREC_REG_STATE, offset);
	346	else
	347	jit_ldxi_i(jit_reg, LIGHTREC_REG_STATE, offset);
	348
d16005f8	349	nreg->loaded = true;
d16005f8 PC	350	}
	351
	352	/* Clear register r0 before use */
	353	if (reg == 0 && (!nreg->loaded \|\| nreg->dirty)) {
	354	jit_movi(jit_reg, 0);
	355	nreg->extended = true;
98fa08a5	356	nreg->zero_extended = true;
d16005f8 PC	357	nreg->loaded = true;
	358	}
	359
	360	nreg->used = true;
	361	nreg->output = false;
	362	nreg->emulated_register = reg;
d16005f8	363
98fa08a5 PC	364	if ((flags & REG_EXT) && !nreg->extended &&
98fa08a5 PC	365	(!nreg->zero_extended \|\| !(flags & REG_ZEXT))) {
d16005f8	366	nreg->extended = true;
98fa08a5	367	nreg->zero_extended = false;
d16005f8	368	jit_extr_i(jit_reg, jit_reg);
98fa08a5 PC	369	} else if (!(flags & REG_EXT) && (flags & REG_ZEXT) &&
	370	!nreg->zero_extended) {
	371	nreg->zero_extended = true;
	372	nreg->extended = false;
	373	jit_extr_ui(jit_reg, jit_reg);
d16005f8	374	}
d16005f8 PC	375
	376	return jit_reg;
	377	}
	378
	379	u8 lightrec_request_reg_in(struct regcache cache, jit_state_t _jit,
	380	u8 reg, u8 jit_reg)
	381	{
	382	struct native_register *nreg;
	383	u16 offset;
	384
	385	nreg = find_mapped_reg(cache, reg, false);
	386	if (nreg) {
	387	jit_reg = lightrec_reg_to_lightning(cache, nreg);
	388	nreg->used = true;
	389	return jit_reg;
	390	}
	391
	392	nreg = lightning_reg_to_lightrec(cache, jit_reg);
	393	lightrec_unload_nreg(cache, _jit, nreg, jit_reg);
	394
	395	/* Load previous value from register cache */
98fa08a5	396	offset = offsetof(struct lightrec_state, regs.gpr) + (reg << 2);
d16005f8 PC	397	jit_ldxi_i(jit_reg, LIGHTREC_REG_STATE, offset);
	398
	399	nreg->extended = true;
98fa08a5	400	nreg->zero_extended = false;
d16005f8 PC	401	nreg->used = true;
	402	nreg->loaded = true;
	403	nreg->emulated_register = reg;
	404
	405	return jit_reg;
	406	}
	407
	408	static void free_reg(struct native_register *nreg)
	409	{
	410	/* Set output registers as dirty */
	411	if (nreg->used && nreg->output && nreg->emulated_register > 0)
	412	nreg->dirty = true;
98fa08a5	413	if (nreg->output) {
d16005f8	414	nreg->extended = nreg->extend;
98fa08a5 PC	415	nreg->zero_extended = nreg->zero_extend;
98fa08a5 PC	416	}
d16005f8 PC	417	nreg->used = false;
	418	}
	419
	420	void lightrec_free_reg(struct regcache *cache, u8 jit_reg)
	421	{
98fa08a5 PC	422	if (!lightrec_reg_is_zero(jit_reg))
98fa08a5 PC	423	free_reg(lightning_reg_to_lightrec(cache, jit_reg));
d16005f8 PC	424	}
	425
	426	void lightrec_free_regs(struct regcache *cache)
	427	{
	428	unsigned int i;
	429
	430	for (i = 0; i < ARRAY_SIZE(cache->lightrec_regs); i++)
	431	free_reg(&cache->lightrec_regs[i]);
	432	}
	433
	434	static void clean_reg(jit_state_t *_jit,
	435	struct native_register *nreg, u8 jit_reg, bool clean)
	436	{
	437	if (nreg->dirty) {
98fa08a5	438	s16 offset = offsetof(struct lightrec_state, regs.gpr)
d16005f8 PC	439	+ (nreg->emulated_register << 2);
	440
	441	jit_stxi_i(offset, LIGHTREC_REG_STATE, jit_reg);
	442	nreg->loaded \|= nreg->dirty;
	443	nreg->dirty ^= clean;
	444	}
	445	}
	446
	447	static void clean_regs(struct regcache cache, jit_state_t _jit, bool clean)
	448	{
	449	unsigned int i;
	450
	451	for (i = 0; i < NUM_REGS; i++)
	452	clean_reg(_jit, &cache->lightrec_regs[i], JIT_V(i), clean);
	453	for (i = 0; i < NUM_TEMPS; i++) {
	454	clean_reg(_jit, &cache->lightrec_regs[i + NUM_REGS],
	455	JIT_R(i), clean);
	456	}
	457	}
	458
	459	void lightrec_storeback_regs(struct regcache cache, jit_state_t _jit)
	460	{
	461	clean_regs(cache, _jit, false);
	462	}
	463
	464	void lightrec_clean_regs(struct regcache cache, jit_state_t _jit)
	465	{
	466	clean_regs(cache, _jit, true);
	467	}
	468
	469	void lightrec_clean_reg(struct regcache cache, jit_state_t _jit, u8 jit_reg)
	470	{
98fa08a5 PC	471	struct native_register *reg;
	472
	473	if (!lightrec_reg_is_zero(jit_reg)) {
	474	reg = lightning_reg_to_lightrec(cache, jit_reg);
	475	clean_reg(_jit, reg, jit_reg, true);
	476	}
d16005f8 PC	477	}
	478
	479	void lightrec_clean_reg_if_loaded(struct regcache cache, jit_state_t _jit,
	480	u8 reg, bool unload)
	481	{
	482	struct native_register *nreg;
	483	u8 jit_reg;
	484
	485	nreg = find_mapped_reg(cache, reg, false);
	486	if (nreg) {
	487	jit_reg = lightrec_reg_to_lightning(cache, nreg);
	488
	489	if (unload)
	490	lightrec_unload_nreg(cache, _jit, nreg, jit_reg);
	491	else
	492	clean_reg(_jit, nreg, jit_reg, true);
	493	}
	494	}
	495
03535202 PC	496	void lightrec_discard_reg_if_loaded(struct regcache *cache, u8 reg)
	497	{
	498	struct native_register *nreg;
	499
	500	nreg = find_mapped_reg(cache, reg, false);
	501	if (nreg)
	502	lightrec_discard_nreg(nreg);
	503	}
	504
d16005f8 PC	505	struct native_register * lightrec_regcache_enter_branch(struct regcache *cache)
	506	{
	507	struct native_register *backup;
	508
	509	backup = lightrec_malloc(cache->state, MEM_FOR_LIGHTREC,
	510	sizeof(cache->lightrec_regs));
	511	memcpy(backup, &cache->lightrec_regs, sizeof(cache->lightrec_regs));
	512
	513	return backup;
	514	}
	515
	516	void lightrec_regcache_leave_branch(struct regcache *cache,
	517	struct native_register *regs)
	518	{
	519	memcpy(&cache->lightrec_regs, regs, sizeof(cache->lightrec_regs));
	520	lightrec_free(cache->state, MEM_FOR_LIGHTREC,
	521	sizeof(cache->lightrec_regs), regs);
	522	}
	523
	524	void lightrec_regcache_reset(struct regcache *cache)
	525	{
	526	memset(&cache->lightrec_regs, 0, sizeof(cache->lightrec_regs));
	527	}
	528
	529	struct regcache * lightrec_regcache_init(struct lightrec_state *state)
	530	{
	531	struct regcache *cache;
	532
	533	cache = lightrec_calloc(state, MEM_FOR_LIGHTREC, sizeof(*cache));
	534	if (!cache)
	535	return NULL;
	536
	537	cache->state = state;
	538
	539	return cache;
	540	}
	541
	542	void lightrec_free_regcache(struct regcache *cache)
	543	{
	544	return lightrec_free(cache->state, MEM_FOR_LIGHTREC,
	545	sizeof(*cache), cache);
	546	}
	547
	548	void lightrec_regcache_mark_live(struct regcache cache, jit_state_t _jit)
	549	{
	550	struct native_register *nreg;
	551	unsigned int i;
	552
	553	#ifdef _WIN32
	554	/* FIXME: GNU Lightning on Windows seems to use our mapped registers as
	555	* temporaries. Until the actual bug is found and fixed, unconditionally
	556	* mark our registers as live here. */
	557	for (i = 0; i < NUM_REGS; i++) {
	558	nreg = &cache->lightrec_regs[i];
	559
	560	if (nreg->used \|\| nreg->loaded \|\| nreg->dirty)
	561	jit_live(JIT_V(i));
	562	}
	563	#endif
	564
	565	for (i = 0; i < NUM_TEMPS; i++) {
	566	nreg = &cache->lightrec_regs[NUM_REGS + i];
	567
	568	if (nreg->used \|\| nreg->loaded \|\| nreg->dirty)
569	jit_live(JIT_R(i));
570	}
571	}