ref: a00b6bdbfa72a1688a866edf5f825720c9874ada
parent: 5cdabc5eb16db432abcf61dc126bfb7f9b2978c1
author: cinap_lenrek <[email protected]>
date: Thu Jun 9 19:12:46 EDT 2016
8c, 6c: native ROL (cyclic shift) instruction support, improve peephole optimizers introduce rolor() function to subsitute (a << c) | (a >> (bits(a) - c)) with (a <<< c) where <<< is cyclic rotation and c is constant. this almost doubles the speed of chacha encryption of 386 and amd64. the peephole optimizer used to stop when it hit a shift or rol instruction when attempting to eleminate moves by register substitution. but we do not have to as long as the shift count operand is not CX (which cannot be substituted) and CX is not a subject for substitution.
--- a/sys/src/cmd/6c/cgen.c
+++ b/sys/src/cmd/6c/cgen.c
@@ -159,6 +159,7 @@
regfree(&nod);
break;
+ case OROL:
case OLSHR:
case OASHL:
case OASHR:
--- a/sys/src/cmd/6c/peep.c
+++ b/sys/src/cmd/6c/peep.c
@@ -370,15 +370,11 @@
break;
p = r->prog;
switch(p->as) {- case ACALL:
- return 0;
-
case AIMULL:
case AIMULQ:
case AIMULW:
if(p->to.type != D_NONE)
break;
-
case ADIVB:
case ADIVL:
case ADIVQ:
@@ -393,6 +389,19 @@
case AMULQ:
case AMULW:
+ case ACWD:
+ case ACDQ:
+ case ACQO:
+
+ case AREP:
+ case AREPN:
+ case ALOOP:
+ case ALOOPEQ:
+ case ALOOPNE:
+
+ case ACALL:
+ return 0;
+
case AROLB:
case AROLL:
case AROLQ:
@@ -417,14 +426,9 @@
case ASHRL:
case ASHRQ:
case ASHRW:
-
- case AREP:
- case AREPN:
-
- case ACWD:
- case ACDQ:
- case ACQO:
- return 0;
+ if(p->from.type == D_CX && v1->type == D_CX)
+ return 0;
+ break;
case AORL:
case AORQ:
--- a/sys/src/cmd/6c/sgen.c
+++ b/sys/src/cmd/6c/sgen.c
@@ -120,7 +120,6 @@
*l = *(n->left);
l->xoffset += r->vconst;
n->left = l;
- r = n->right;
goto brk;
}
break;
@@ -212,7 +211,6 @@
if(g >= 0) {n->left = r;
n->right = l;
- l = r;
r = n->right;
}
g = vlog(r);
@@ -288,6 +286,12 @@
indexshift(n);
break;
+ case OOR:
+ xcom(l);
+ xcom(r);
+ rolor(n);
+ break;
+
default:
if(l != Z)
xcom(l);
@@ -298,6 +302,8 @@
brk:
if(n->addable >= 10)
return;
+ l = n->left;
+ r = n->right;
if(l != Z)
n->complex = l->complex;
if(r != Z) {@@ -344,6 +350,7 @@
}
break;
+ case OROL:
case OLSHR:
case OASHL:
case OASHR:
--- a/sys/src/cmd/6c/txt.c
+++ b/sys/src/cmd/6c/txt.c
@@ -1305,6 +1305,16 @@
a = ASALQ;
break;
+ case OROL:
+ a = AROLL;
+ if(et == TCHAR || et == TUCHAR)
+ a = AROLB;
+ if(et == TSHORT || et == TUSHORT)
+ a = AROLW;
+ if(et == TVLONG || et == TUVLONG || et == TIND)
+ a = AROLQ;
+ break;
+
case OFUNC:
a = ACALL;
break;
--- a/sys/src/cmd/8c/cgen.c
+++ b/sys/src/cmd/8c/cgen.c
@@ -178,6 +178,7 @@
regfree(&nod);
break;
+ case OROL:
case OLSHR:
case OASHL:
case OASHR:
--- a/sys/src/cmd/8c/peep.c
+++ b/sys/src/cmd/8c/peep.c
@@ -264,9 +264,6 @@
break;
p = r->prog;
switch(p->as) {- case ACALL:
- return 0;
-
case AIMULL:
case AIMULW:
if(p->to.type != D_NONE)
@@ -283,6 +280,23 @@
case AMULL:
case AMULW:
+ case AREP:
+ case AREPN:
+ case ALOOP:
+ case ALOOPNE:
+
+ case ACWD:
+ case ACDQ:
+
+ case ASTOSB:
+ case ASTOSL:
+ case AMOVSB:
+ case AMOVSL:
+ case AFSTSW:
+
+ case ACALL:
+ return 0;
+
case AROLB:
case AROLL:
case AROLW:
@@ -301,19 +315,9 @@
case ASHRB:
case ASHRL:
case ASHRW:
-
- case AREP:
- case AREPN:
-
- case ACWD:
- case ACDQ:
-
- case ASTOSB:
- case ASTOSL:
- case AMOVSB:
- case AMOVSL:
- case AFSTSW:
- return 0;
+ if(p->from.type == D_CX && v1->type == D_CX)
+ return 0;
+ break;
case AORL:
case AANDL:
--- a/sys/src/cmd/8c/sgen.c
+++ b/sys/src/cmd/8c/sgen.c
@@ -127,7 +127,6 @@
*l = *(n->left);
l->xoffset += r->vconst;
n->left = l;
- r = n->right;
goto brk;
}
break;
@@ -219,7 +218,6 @@
if(g >= 0) {n->left = r;
n->right = l;
- l = r;
r = n->right;
}
g = vlog(r);
@@ -230,7 +228,7 @@
indexshift(n);
break;
}
-commute(n);
+ commute(n);
break;
case OASLDIV:
@@ -295,6 +293,13 @@
indexshift(n);
break;
+ case OOR:
+ xcom(l);
+ xcom(r);
+ if(typechl[n->type->etype])
+ rolor(n);
+ break;
+
default:
if(l != Z)
xcom(l);
@@ -305,6 +310,8 @@
brk:
if(n->addable >= 10)
return;
+ l = n->left;
+ r = n->right;
if(l != Z)
n->complex = l->complex;
if(r != Z) {@@ -349,6 +356,7 @@
}
break;
+ case OROL:
case OLSHR:
case OASHL:
case OASHR:
--- a/sys/src/cmd/8c/txt.c
+++ b/sys/src/cmd/8c/txt.c
@@ -1238,6 +1238,14 @@
a = ASALW;
break;
+ case OROL:
+ a = AROLL;
+ if(et == TCHAR || et == TUCHAR)
+ a = AROLB;
+ if(et == TSHORT || et == TUSHORT)
+ a = AROLW;
+ break;
+
case OFUNC:
a = ACALL;
break;
--- a/sys/src/cmd/cc/cc.h
+++ b/sys/src/cmd/cc/cc.h
@@ -273,6 +273,7 @@
OPROTO,
OREGISTER,
ORETURN,
+ OROL,
OSET,
OSIGN,
OSIZE,
@@ -694,6 +695,7 @@
int vlog(Node*);
int topbit(ulong);
void simplifyshift(Node*);
+void rolor(Node*);
long typebitor(long, long);
void diag(Node*, char*, ...);
void warn(Node*, char*, ...);
--- a/sys/src/cmd/cc/sub.c
+++ b/sys/src/cmd/cc/sub.c
@@ -903,6 +903,46 @@
n->left->op = o;
}
+/*
+ * replace shift/or with rotate left
+ */
+void
+rolor(Node *n)
+{+ Node *l, *r;
+
+ if(!typeu[n->type->etype])
+ return;
+
+ l = n->left;
+ r = n->right;
+ switch(l->op){+ case OASHL:
+ if(r->op == OLSHR)
+ break;
+ return;
+ case OLSHR:
+ if(r->op == OASHL){+ r = l;
+ l = n->right;
+ break;
+ }
+ default:
+ return;
+ }
+ if(l->right->op != OCONST || r->right->op != OCONST)
+ return;
+ if(vconst(l->right) + vconst(r->right) != ewidth[n->type->etype]*8)
+ return;
+ if(l->left->type != n->type || r->left->type != n->type)
+ return;
+ if(l->left->op != ONAME || r->left->op != ONAME || l->left->sym != r->left->sym)
+ return;
+
+ *n = *l;
+ n->op = OROL;
+}
+
int
side(Node *n)
{@@ -1473,6 +1513,7 @@
OPROTO, 0, "PROTO",
OREGISTER, 0, "REGISTER",
ORETURN, 0, "RETURN",
+ OROL, 0, "ROL",
OSET, 0, "SET",
OSIGN, 0, "SIGN",
OSIZE, 0, "SIZE",