From 70fac59a2ae334c5994037b45a76f8dc9f034ab5 Mon Sep 17 00:00:00 2001 From: Richard Henderson Date: Tue, 2 Apr 2013 15:16:10 -0700 Subject: [PATCH] tcg-ppc64: Use ISEL for setcond There are a few simple special cases that should be handled first. Break these out to subroutines to avoid code duplication. Reviewed-by: Aurelien Jarno Signed-off-by: Richard Henderson --- tcg/ppc64/tcg-target.c | 187 +++++++++++++++++++++++++++-------------- 1 file changed, 122 insertions(+), 65 deletions(-) diff --git a/tcg/ppc64/tcg-target.c b/tcg/ppc64/tcg-target.c index c7800b0929..df62cda6f1 100644 --- a/tcg/ppc64/tcg-target.c +++ b/tcg/ppc64/tcg-target.c @@ -45,6 +45,7 @@ static uint8_t *tb_ret_addr; #endif #define HAVE_ISA_2_06 0 +#define HAVE_ISEL 0 #ifdef CONFIG_USE_GUEST_BASE #define TCG_GUEST_BASE_REG 30 @@ -390,6 +391,7 @@ static int tcg_target_const_match (tcg_target_long val, #define ORC XO31(412) #define EQV XO31(284) #define NAND XO31(476) +#define ISEL XO31( 15) #define MULLD XO31(233) #define MULHD XO31( 73) @@ -445,6 +447,7 @@ static int tcg_target_const_match (tcg_target_long val, #define BT(n, c) (((c)+((n)*4))<<21) #define BA(n, c) (((c)+((n)*4))<<16) #define BB(n, c) (((c)+((n)*4))<<11) +#define BC_(n, c) (((c)+((n)*4))<<6) #define BO_COND_TRUE BO (12) #define BO_COND_FALSE BO ( 4) @@ -470,6 +473,20 @@ static const uint32_t tcg_to_bc[] = { [TCG_COND_GTU] = BC | BI (7, CR_GT) | BO_COND_TRUE, }; +/* The low bit here is set if the RA and RB fields must be inverted. */ +static const uint32_t tcg_to_isel[] = { + [TCG_COND_EQ] = ISEL | BC_(7, CR_EQ), + [TCG_COND_NE] = ISEL | BC_(7, CR_EQ) | 1, + [TCG_COND_LT] = ISEL | BC_(7, CR_LT), + [TCG_COND_GE] = ISEL | BC_(7, CR_LT) | 1, + [TCG_COND_LE] = ISEL | BC_(7, CR_GT) | 1, + [TCG_COND_GT] = ISEL | BC_(7, CR_GT), + [TCG_COND_LTU] = ISEL | BC_(7, CR_LT), + [TCG_COND_GEU] = ISEL | BC_(7, CR_LT) | 1, + [TCG_COND_LEU] = ISEL | BC_(7, CR_GT) | 1, + [TCG_COND_GTU] = ISEL | BC_(7, CR_GT), +}; + static inline void tcg_out_mov(TCGContext *s, TCGType type, TCGReg ret, TCGReg arg) { @@ -1131,79 +1148,119 @@ static void tcg_out_cmp(TCGContext *s, int cond, TCGArg arg1, TCGArg arg2, } } -static void tcg_out_setcond (TCGContext *s, TCGType type, TCGCond cond, - TCGArg arg0, TCGArg arg1, TCGArg arg2, - int const_arg2) +static void tcg_out_setcond_eq0(TCGContext *s, TCGType type, + TCGReg dst, TCGReg src) { - int crop, sh, arg; + tcg_out32(s, (type == TCG_TYPE_I64 ? CNTLZD : CNTLZW) | RS(src) | RA(dst)); + tcg_out_shri64(s, dst, dst, type == TCG_TYPE_I64 ? 6 : 5); +} + +static void tcg_out_setcond_ne0(TCGContext *s, TCGReg dst, TCGReg src) +{ + /* X != 0 implies X + -1 generates a carry. Extra addition + trickery means: R = X-1 + ~X + C = X-1 + (-X+1) + C = C. */ + if (dst != src) { + tcg_out32(s, ADDIC | TAI(dst, src, -1)); + tcg_out32(s, SUBFE | TAB(dst, dst, src)); + } else { + tcg_out32(s, ADDIC | TAI(0, src, -1)); + tcg_out32(s, SUBFE | TAB(dst, 0, src)); + } +} + +static TCGReg tcg_gen_setcond_xor(TCGContext *s, TCGReg arg1, TCGArg arg2, + bool const_arg2) +{ + if (const_arg2) { + if ((uint32_t)arg2 == arg2) { + tcg_out_xori32(s, TCG_REG_R0, arg1, arg2); + } else { + tcg_out_movi(s, TCG_TYPE_I64, TCG_REG_R0, arg2); + tcg_out32(s, XOR | SAB(arg1, TCG_REG_R0, TCG_REG_R0)); + } + } else { + tcg_out32(s, XOR | SAB(arg1, TCG_REG_R0, arg2)); + } + return TCG_REG_R0; +} + +static void tcg_out_setcond(TCGContext *s, TCGType type, TCGCond cond, + TCGArg arg0, TCGArg arg1, TCGArg arg2, + int const_arg2) +{ + int crop, sh; + + /* Ignore high bits of a potential constant arg2. */ + if (type == TCG_TYPE_I32) { + arg2 = (uint32_t)arg2; + } + + /* Handle common and trivial cases before handling anything else. */ + if (arg2 == 0) { + switch (cond) { + case TCG_COND_EQ: + tcg_out_setcond_eq0(s, type, arg0, arg1); + return; + case TCG_COND_NE: + if (type == TCG_TYPE_I32) { + tcg_out_ext32u(s, TCG_REG_R0, arg1); + arg1 = TCG_REG_R0; + } + tcg_out_setcond_ne0(s, arg0, arg1); + return; + case TCG_COND_GE: + tcg_out32(s, NOR | SAB(arg1, arg0, arg1)); + arg1 = arg0; + /* FALLTHRU */ + case TCG_COND_LT: + /* Extract the sign bit. */ + tcg_out_rld(s, RLDICL, arg0, arg1, + type == TCG_TYPE_I64 ? 1 : 33, 63); + return; + default: + break; + } + } + + /* If we have ISEL, we can implement everything with 3 or 4 insns. + All other cases below are also at least 3 insns, so speed up the + code generator by not considering them and always using ISEL. */ + if (HAVE_ISEL) { + int isel, tab; + + tcg_out_cmp(s, cond, arg1, arg2, const_arg2, 7, type); + + isel = tcg_to_isel[cond]; + + tcg_out_movi(s, type, arg0, 1); + if (isel & 1) { + /* arg0 = (bc ? 0 : 1) */ + tab = TAB(arg0, 0, arg0); + isel &= ~1; + } else { + /* arg0 = (bc ? 1 : 0) */ + tcg_out_movi(s, type, TCG_REG_R0, 0); + tab = TAB(arg0, arg0, TCG_REG_R0); + } + tcg_out32(s, isel | tab); + return; + } switch (cond) { case TCG_COND_EQ: - if (const_arg2) { - if (!arg2) { - arg = arg1; - } - else { - arg = 0; - if ((uint16_t) arg2 == arg2) { - tcg_out32(s, XORI | SAI(arg1, 0, arg2)); - } - else { - tcg_out_movi (s, type, 0, arg2); - tcg_out32 (s, XOR | SAB (arg1, 0, 0)); - } - } - } - else { - arg = 0; - tcg_out32 (s, XOR | SAB (arg1, 0, arg2)); - } - - if (type == TCG_TYPE_I64) { - tcg_out32 (s, CNTLZD | RS (arg) | RA (0)); - tcg_out_rld (s, RLDICL, arg0, 0, 58, 6); - } - else { - tcg_out32 (s, CNTLZW | RS (arg) | RA (0)); - tcg_out_rlw(s, RLWINM, arg0, 0, 27, 5, 31); - } - break; + arg1 = tcg_gen_setcond_xor(s, arg1, arg2, const_arg2); + tcg_out_setcond_eq0(s, type, arg0, arg1); + return; case TCG_COND_NE: - if (const_arg2) { - if (!arg2) { - arg = arg1; - } - else { - arg = 0; - if ((uint16_t) arg2 == arg2) { - tcg_out32(s, XORI | SAI(arg1, 0, arg2)); - } else { - tcg_out_movi (s, type, 0, arg2); - tcg_out32 (s, XOR | SAB (arg1, 0, 0)); - } - } - } - else { - arg = 0; - tcg_out32 (s, XOR | SAB (arg1, 0, arg2)); - } - - /* Make sure and discard the high 32-bits of the input. */ + arg1 = tcg_gen_setcond_xor(s, arg1, arg2, const_arg2); + /* Discard the high bits only once, rather than both inputs. */ if (type == TCG_TYPE_I32) { - tcg_out32(s, EXTSW | RA(TCG_REG_R0) | RS(arg)); - arg = TCG_REG_R0; + tcg_out_ext32u(s, TCG_REG_R0, arg1); + arg1 = TCG_REG_R0; } - - if (arg == arg1 && arg1 == arg0) { - tcg_out32(s, ADDIC | TAI(0, arg, -1)); - tcg_out32(s, SUBFE | TAB(arg0, 0, arg)); - } - else { - tcg_out32(s, ADDIC | TAI(arg0, arg, -1)); - tcg_out32(s, SUBFE | TAB(arg0, arg0, arg)); - } - break; + tcg_out_setcond_ne0(s, arg0, arg1); + return; case TCG_COND_GT: case TCG_COND_GTU: