target/ppc: Use atomic load for LQ and LQARX

Section 1.4 of the Power ISA v3.0B states that both of these
instructions are single-copy atomic.  As we cannot (yet) issue
128-bit loads within TCG, use the generic helpers provided.

Since TCG cannot (yet) return a 128-bit value, add a slot within
CPUPPCState for returning the high half of a 128-bit return value.
This solution is preferred to the helper assigning to architectural
registers directly, as it avoids clobbering all TCG live values.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
This commit is contained in:
Richard Henderson 2018-06-26 09:19:10 -07:00 committed by David Gibson
parent 0f3110fa67
commit 94bf265867
4 changed files with 95 additions and 26 deletions

View File

@ -1015,6 +1015,9 @@ struct CPUPPCState {
/* Next instruction pointer */ /* Next instruction pointer */
target_ulong nip; target_ulong nip;
/* High part of 128-bit helper return. */
uint64_t retxh;
int access_type; /* when a memory exception occurs, the access int access_type; /* when a memory exception occurs, the access
type is stored here */ type is stored here */

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@ -799,3 +799,8 @@ DEF_HELPER_4(dscliq, void, env, fprp, fprp, i32)
DEF_HELPER_1(tbegin, void, env) DEF_HELPER_1(tbegin, void, env)
DEF_HELPER_FLAGS_1(fixup_thrm, TCG_CALL_NO_RWG, void, env) DEF_HELPER_FLAGS_1(fixup_thrm, TCG_CALL_NO_RWG, void, env)
#if defined(TARGET_PPC64) && defined(CONFIG_ATOMIC128)
DEF_HELPER_FLAGS_3(lq_le_parallel, TCG_CALL_NO_WG, i64, env, tl, i32)
DEF_HELPER_FLAGS_3(lq_be_parallel, TCG_CALL_NO_WG, i64, env, tl, i32)
#endif

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@ -21,9 +21,9 @@
#include "exec/exec-all.h" #include "exec/exec-all.h"
#include "qemu/host-utils.h" #include "qemu/host-utils.h"
#include "exec/helper-proto.h" #include "exec/helper-proto.h"
#include "helper_regs.h" #include "helper_regs.h"
#include "exec/cpu_ldst.h" #include "exec/cpu_ldst.h"
#include "tcg.h"
#include "internal.h" #include "internal.h"
//#define DEBUG_OP //#define DEBUG_OP
@ -215,6 +215,24 @@ target_ulong helper_lscbx(CPUPPCState *env, target_ulong addr, uint32_t reg,
return i; return i;
} }
#if defined(TARGET_PPC64) && defined(CONFIG_ATOMIC128)
uint64_t helper_lq_le_parallel(CPUPPCState *env, target_ulong addr,
uint32_t opidx)
{
Int128 ret = helper_atomic_ldo_le_mmu(env, addr, opidx, GETPC());
env->retxh = int128_gethi(ret);
return int128_getlo(ret);
}
uint64_t helper_lq_be_parallel(CPUPPCState *env, target_ulong addr,
uint32_t opidx)
{
Int128 ret = helper_atomic_ldo_be_mmu(env, addr, opidx, GETPC());
env->retxh = int128_gethi(ret);
return int128_getlo(ret);
}
#endif
/*****************************************************************************/ /*****************************************************************************/
/* Altivec extension helpers */ /* Altivec extension helpers */
#if defined(HOST_WORDS_BIGENDIAN) #if defined(HOST_WORDS_BIGENDIAN)

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@ -2607,7 +2607,7 @@ static void gen_ld(DisasContext *ctx)
static void gen_lq(DisasContext *ctx) static void gen_lq(DisasContext *ctx)
{ {
int ra, rd; int ra, rd;
TCGv EA; TCGv EA, hi, lo;
/* lq is a legal user mode instruction starting in ISA 2.07 */ /* lq is a legal user mode instruction starting in ISA 2.07 */
bool legal_in_user_mode = (ctx->insns_flags2 & PPC2_LSQ_ISA207) != 0; bool legal_in_user_mode = (ctx->insns_flags2 & PPC2_LSQ_ISA207) != 0;
@ -2633,16 +2633,35 @@ static void gen_lq(DisasContext *ctx)
EA = tcg_temp_new(); EA = tcg_temp_new();
gen_addr_imm_index(ctx, EA, 0x0F); gen_addr_imm_index(ctx, EA, 0x0F);
/* We only need to swap high and low halves. gen_qemu_ld64_i64 does /* Note that the low part is always in RD+1, even in LE mode. */
necessary 64-bit byteswap already. */ lo = cpu_gpr[rd + 1];
if (unlikely(ctx->le_mode)) { hi = cpu_gpr[rd];
gen_qemu_ld64_i64(ctx, cpu_gpr[rd + 1], EA);
if (tb_cflags(ctx->base.tb) & CF_PARALLEL) {
#ifdef CONFIG_ATOMIC128
TCGv_i32 oi = tcg_temp_new_i32();
if (ctx->le_mode) {
tcg_gen_movi_i32(oi, make_memop_idx(MO_LEQ, ctx->mem_idx));
gen_helper_lq_le_parallel(lo, cpu_env, EA, oi);
} else {
tcg_gen_movi_i32(oi, make_memop_idx(MO_BEQ, ctx->mem_idx));
gen_helper_lq_be_parallel(lo, cpu_env, EA, oi);
}
tcg_temp_free_i32(oi);
tcg_gen_ld_i64(hi, cpu_env, offsetof(CPUPPCState, retxh));
#else
/* Restart with exclusive lock. */
gen_helper_exit_atomic(cpu_env);
ctx->base.is_jmp = DISAS_NORETURN;
#endif
} else if (ctx->le_mode) {
tcg_gen_qemu_ld_i64(lo, EA, ctx->mem_idx, MO_LEQ);
gen_addr_add(ctx, EA, EA, 8); gen_addr_add(ctx, EA, EA, 8);
gen_qemu_ld64_i64(ctx, cpu_gpr[rd], EA); tcg_gen_qemu_ld_i64(hi, EA, ctx->mem_idx, MO_LEQ);
} else { } else {
gen_qemu_ld64_i64(ctx, cpu_gpr[rd], EA); tcg_gen_qemu_ld_i64(hi, EA, ctx->mem_idx, MO_BEQ);
gen_addr_add(ctx, EA, EA, 8); gen_addr_add(ctx, EA, EA, 8);
gen_qemu_ld64_i64(ctx, cpu_gpr[rd + 1], EA); tcg_gen_qemu_ld_i64(lo, EA, ctx->mem_idx, MO_BEQ);
} }
tcg_temp_free(EA); tcg_temp_free(EA);
} }
@ -3236,9 +3255,8 @@ STCX(stdcx_, DEF_MEMOP(MO_Q))
/* lqarx */ /* lqarx */
static void gen_lqarx(DisasContext *ctx) static void gen_lqarx(DisasContext *ctx)
{ {
TCGv EA;
int rd = rD(ctx->opcode); int rd = rD(ctx->opcode);
TCGv gpr1, gpr2; TCGv EA, hi, lo;
if (unlikely((rd & 1) || (rd == rA(ctx->opcode)) || if (unlikely((rd & 1) || (rd == rA(ctx->opcode)) ||
(rd == rB(ctx->opcode)))) { (rd == rB(ctx->opcode)))) {
@ -3247,24 +3265,49 @@ static void gen_lqarx(DisasContext *ctx)
} }
gen_set_access_type(ctx, ACCESS_RES); gen_set_access_type(ctx, ACCESS_RES);
EA = tcg_temp_local_new(); EA = tcg_temp_new();
gen_addr_reg_index(ctx, EA); gen_addr_reg_index(ctx, EA);
gen_check_align(ctx, EA, 15);
if (unlikely(ctx->le_mode)) {
gpr1 = cpu_gpr[rd+1];
gpr2 = cpu_gpr[rd];
} else {
gpr1 = cpu_gpr[rd];
gpr2 = cpu_gpr[rd+1];
}
tcg_gen_qemu_ld_i64(gpr1, EA, ctx->mem_idx, DEF_MEMOP(MO_Q));
tcg_gen_mov_tl(cpu_reserve, EA);
gen_addr_add(ctx, EA, EA, 8);
tcg_gen_qemu_ld_i64(gpr2, EA, ctx->mem_idx, DEF_MEMOP(MO_Q));
tcg_gen_st_tl(gpr1, cpu_env, offsetof(CPUPPCState, reserve_val)); /* Note that the low part is always in RD+1, even in LE mode. */
tcg_gen_st_tl(gpr2, cpu_env, offsetof(CPUPPCState, reserve_val2)); lo = cpu_gpr[rd + 1];
hi = cpu_gpr[rd];
if (tb_cflags(ctx->base.tb) & CF_PARALLEL) {
#ifdef CONFIG_ATOMIC128
TCGv_i32 oi = tcg_temp_new_i32();
if (ctx->le_mode) {
tcg_gen_movi_i32(oi, make_memop_idx(MO_LEQ | MO_ALIGN_16,
ctx->mem_idx));
gen_helper_lq_le_parallel(lo, cpu_env, EA, oi);
} else {
tcg_gen_movi_i32(oi, make_memop_idx(MO_BEQ | MO_ALIGN_16,
ctx->mem_idx));
gen_helper_lq_be_parallel(lo, cpu_env, EA, oi);
}
tcg_temp_free_i32(oi);
tcg_gen_ld_i64(hi, cpu_env, offsetof(CPUPPCState, retxh));
#else
/* Restart with exclusive lock. */
gen_helper_exit_atomic(cpu_env);
ctx->base.is_jmp = DISAS_NORETURN;
tcg_temp_free(EA);
return;
#endif
} else if (ctx->le_mode) {
tcg_gen_qemu_ld_i64(lo, EA, ctx->mem_idx, MO_LEQ | MO_ALIGN_16);
tcg_gen_mov_tl(cpu_reserve, EA);
gen_addr_add(ctx, EA, EA, 8);
tcg_gen_qemu_ld_i64(hi, EA, ctx->mem_idx, MO_LEQ);
} else {
tcg_gen_qemu_ld_i64(hi, EA, ctx->mem_idx, MO_BEQ | MO_ALIGN_16);
tcg_gen_mov_tl(cpu_reserve, EA);
gen_addr_add(ctx, EA, EA, 8);
tcg_gen_qemu_ld_i64(lo, EA, ctx->mem_idx, MO_BEQ);
}
tcg_temp_free(EA); tcg_temp_free(EA);
tcg_gen_st_tl(hi, cpu_env, offsetof(CPUPPCState, reserve_val));
tcg_gen_st_tl(lo, cpu_env, offsetof(CPUPPCState, reserve_val2));
} }
/* stqcx. */ /* stqcx. */