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author | Richard Henderson <rth@twiddle.net> | 2014-01-28 11:39:49 -0800 |
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committer | Richard Henderson <rth@twiddle.net> | 2014-02-17 10:12:29 -0600 |
commit | 6399ab3325b7d4f77441c8a00fa9dae98bb0ac43 (patch) | |
tree | 4775b16d8a9bf4da32cd8b083c7b4ebb40975a06 /tcg/i386 | |
parent | 9d2eec202fad72ce05ee8d54dc5a6fb6dcb87776 (diff) | |
download | hqemu-6399ab3325b7d4f77441c8a00fa9dae98bb0ac43.zip hqemu-6399ab3325b7d4f77441c8a00fa9dae98bb0ac43.tar.gz |
tcg/i386: Use SHLX/SHRX/SARX instructions
These three-operand shift instructions do not require the shift count
to be placed into ECX. This reduces the number of mov insns required,
with the mere addition of a new register constraint.
Don't attempt to get rid of the matching constraint, as that's impossible
to manipulate with just a new constraint. In addition, constant shifts
still need the matching constraint.
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg/i386')
-rw-r--r-- | tcg/i386/tcg-target.c | 61 |
1 files changed, 50 insertions, 11 deletions
diff --git a/tcg/i386/tcg-target.c b/tcg/i386/tcg-target.c index 4f6b9c1..fef1717 100644 --- a/tcg/i386/tcg-target.c +++ b/tcg/i386/tcg-target.c @@ -133,6 +133,12 @@ static bool have_movbe; it there. Therefore we always define the variable. */ bool have_bmi1; +#if defined(CONFIG_CPUID_H) && defined(bit_BMI2) +static bool have_bmi2; +#else +# define have_bmi2 0 +#endif + static uint8_t *tb_ret_addr; static void patch_reloc(uint8_t *code_ptr, int type, @@ -175,6 +181,7 @@ static int target_parse_constraint(TCGArgConstraint *ct, const char **pct_str) tcg_regset_set_reg(ct->u.regs, TCG_REG_EBX); break; case 'c': + case_c: ct->ct |= TCG_CT_REG; tcg_regset_set_reg(ct->u.regs, TCG_REG_ECX); break; @@ -203,6 +210,7 @@ static int target_parse_constraint(TCGArgConstraint *ct, const char **pct_str) tcg_regset_set32(ct->u.regs, 0, 0xf); break; case 'r': + case_r: ct->ct |= TCG_CT_REG; if (TCG_TARGET_REG_BITS == 64) { tcg_regset_set32(ct->u.regs, 0, 0xffff); @@ -210,6 +218,13 @@ static int target_parse_constraint(TCGArgConstraint *ct, const char **pct_str) tcg_regset_set32(ct->u.regs, 0, 0xff); } break; + case 'C': + /* With SHRX et al, we need not use ECX as shift count register. */ + if (have_bmi2) { + goto case_r; + } else { + goto case_c; + } /* qemu_ld/st address constraint */ case 'L': @@ -283,6 +298,8 @@ static inline int tcg_target_const_match(tcg_target_long val, # define P_REXB_RM 0 # define P_GS 0 #endif +#define P_SIMDF3 0x10000 /* 0xf3 opcode prefix */ +#define P_SIMDF2 0x20000 /* 0xf2 opcode prefix */ #define OPC_ARITH_EvIz (0x81) #define OPC_ARITH_EvIb (0x83) @@ -325,6 +342,9 @@ static inline int tcg_target_const_match(tcg_target_long val, #define OPC_SHIFT_1 (0xd1) #define OPC_SHIFT_Ib (0xc1) #define OPC_SHIFT_cl (0xd3) +#define OPC_SARX (0xf7 | P_EXT38 | P_SIMDF3) +#define OPC_SHLX (0xf7 | P_EXT38 | P_DATA16) +#define OPC_SHRX (0xf7 | P_EXT38 | P_SIMDF2) #define OPC_TESTL (0x85) #define OPC_XCHG_ax_r32 (0x90) @@ -493,7 +513,14 @@ static void tcg_out_vex_modrm(TCGContext *s, int opc, int r, int v, int rm) tmp = (r & 8 ? 0 : 0x80); /* VEX.R */ } - tmp |= (opc & P_DATA16 ? 1 : 0); /* VEX.pp */ + /* VEX.pp */ + if (opc & P_DATA16) { + tmp |= 1; /* 0x66 */ + } else if (opc & P_SIMDF3) { + tmp |= 2; /* 0xf3 */ + } else if (opc & P_SIMDF2) { + tmp |= 3; /* 0xf2 */ + } tmp |= (~v & 15) << 3; /* VEX.vvvv */ tcg_out8(s, tmp); tcg_out8(s, opc); @@ -1689,7 +1716,7 @@ static void tcg_out_qemu_st(TCGContext *s, const TCGArg *args, bool is64) static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, const TCGArg *args, const int *const_args) { - int c, rexw = 0; + int c, vexop, rexw = 0; #if TCG_TARGET_REG_BITS == 64 # define OP_32_64(x) \ @@ -1860,19 +1887,28 @@ static inline void tcg_out_op(TCGContext *s, TCGOpcode opc, OP_32_64(shl): c = SHIFT_SHL; - goto gen_shift; + vexop = OPC_SHLX; + goto gen_shift_maybe_vex; OP_32_64(shr): c = SHIFT_SHR; - goto gen_shift; + vexop = OPC_SHRX; + goto gen_shift_maybe_vex; OP_32_64(sar): c = SHIFT_SAR; - goto gen_shift; + vexop = OPC_SARX; + goto gen_shift_maybe_vex; OP_32_64(rotl): c = SHIFT_ROL; goto gen_shift; OP_32_64(rotr): c = SHIFT_ROR; goto gen_shift; + gen_shift_maybe_vex: + if (have_bmi2 && !const_args[2]) { + tcg_out_vex_modrm(s, vexop + rexw, args[0], args[2], args[1]); + break; + } + /* FALLTHRU */ gen_shift: if (const_args[2]) { tcg_out_shifti(s, c + rexw, args[0], args[2]); @@ -2065,9 +2101,9 @@ static const TCGTargetOpDef x86_op_defs[] = { { INDEX_op_xor_i32, { "r", "0", "ri" } }, { INDEX_op_andc_i32, { "r", "r", "ri" } }, - { INDEX_op_shl_i32, { "r", "0", "ci" } }, - { INDEX_op_shr_i32, { "r", "0", "ci" } }, - { INDEX_op_sar_i32, { "r", "0", "ci" } }, + { INDEX_op_shl_i32, { "r", "0", "Ci" } }, + { INDEX_op_shr_i32, { "r", "0", "Ci" } }, + { INDEX_op_sar_i32, { "r", "0", "Ci" } }, { INDEX_op_rotl_i32, { "r", "0", "ci" } }, { INDEX_op_rotr_i32, { "r", "0", "ci" } }, @@ -2123,9 +2159,9 @@ static const TCGTargetOpDef x86_op_defs[] = { { INDEX_op_xor_i64, { "r", "0", "re" } }, { INDEX_op_andc_i64, { "r", "r", "rI" } }, - { INDEX_op_shl_i64, { "r", "0", "ci" } }, - { INDEX_op_shr_i64, { "r", "0", "ci" } }, - { INDEX_op_sar_i64, { "r", "0", "ci" } }, + { INDEX_op_shl_i64, { "r", "0", "Ci" } }, + { INDEX_op_shr_i64, { "r", "0", "Ci" } }, + { INDEX_op_sar_i64, { "r", "0", "Ci" } }, { INDEX_op_rotl_i64, { "r", "0", "ci" } }, { INDEX_op_rotr_i64, { "r", "0", "ci" } }, @@ -2283,6 +2319,9 @@ static void tcg_target_init(TCGContext *s) #ifdef bit_BMI have_bmi1 = (b & bit_BMI) != 0; #endif +#ifndef have_bmi2 + have_bmi2 = (b & bit_BMI2) != 0; +#endif } if (TCG_TARGET_REG_BITS == 64) { |