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authorRichard Henderson <rth@twiddle.net>2013-04-02 15:16:10 -0700
committerRichard Henderson <rth@twiddle.net>2013-04-15 20:09:53 +0200
commit70fac59a2ae334c5994037b45a76f8dc9f034ab5 (patch)
treea5fe4f12d246c4b0021c46595af9cb7fa001b3ae /tcg
parent6995a4a063d3ab3ceb21aad8c8a78f4cfc5e4140 (diff)
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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 <aurelien@aurel32.net> Signed-off-by: Richard Henderson <rth@twiddle.net>
Diffstat (limited to 'tcg')
-rw-r--r--tcg/ppc64/tcg-target.c181
1 files changed, 119 insertions, 62 deletions
diff --git a/tcg/ppc64/tcg-target.c b/tcg/ppc64/tcg-target.c
index c7800b0..df62cda 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);
+}
- 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));
- }
+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));
+ }
+}
- 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);
+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));
}
- break;
+ } else {
+ tcg_out32(s, XOR | SAB(arg1, TCG_REG_R0, arg2));
+ }
+ return TCG_REG_R0;
+}
- 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));
- }
+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;
}
- else {
- arg = 0;
- tcg_out32 (s, XOR | SAB (arg1, 0, arg2));
- }
+ }
- /* Make sure and discard the high 32-bits of the input. */
- if (type == TCG_TYPE_I32) {
- tcg_out32(s, EXTSW | RA(TCG_REG_R0) | RS(arg));
- arg = TCG_REG_R0;
- }
+ /* 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];
- if (arg == arg1 && arg1 == arg0) {
- tcg_out32(s, ADDIC | TAI(0, arg, -1));
- tcg_out32(s, SUBFE | TAB(arg0, 0, arg));
+ 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);
}
- else {
- tcg_out32(s, ADDIC | TAI(arg0, arg, -1));
- tcg_out32(s, SUBFE | TAB(arg0, arg0, arg));
+ tcg_out32(s, isel | tab);
+ return;
+ }
+
+ switch (cond) {
+ case TCG_COND_EQ:
+ arg1 = tcg_gen_setcond_xor(s, arg1, arg2, const_arg2);
+ tcg_out_setcond_eq0(s, type, arg0, arg1);
+ return;
+
+ case TCG_COND_NE:
+ 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_out_ext32u(s, TCG_REG_R0, arg1);
+ arg1 = TCG_REG_R0;
}
- break;
+ tcg_out_setcond_ne0(s, arg0, arg1);
+ return;
case TCG_COND_GT:
case TCG_COND_GTU: