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Fix floating point comparison.

    We now generate appropriate assembly. Hopefully.

--- a/6/insns.def

+++ b/6/insns.def

@@ -62,7 +62,7 @@

 Insn(Icvttsi2sd, "\tcvttsd2si%2t %x,%r\n",      Use(.l={1}),                    Def(.l={2}))

 Insn(Ifdiv,      "\tdiv%t %x,%r\n",             Use(.l={1},.r={Reax,Redx}),     Def(.r={Reax,Redx}))

 Insn(Ifmul,      "\tmul%t %x,%r\n",             Use(.l={1,2}),                  Def(.l={2}))

-Insn(Icomi,      "\tcomi%d %x,%r\n",            Use(.l={1,2}),                  Def())

+Insn(Icomi,      "\tcomi%t %x,%r\n",            Use(.l={1,2}),                  Def())

 /* branch instructions */

 Insn(Icall,     "\tcall %v\n",                  Use(.l={1}), Def(.r={Rrax}))

--- a/6/isel.c

+++ b/6/isel.c

@@ -40,17 +40,18 @@

 /* used to decide which operator is appropriate

  * for implementing various conditional operators */

 struct {

-    AsmOp test;

+    AsmOp itest;

+    AsmOp fptest;

     AsmOp jmp;

     AsmOp getflag;

 } reloptab[Numops] = {

-    [Olnot] = {Itest, Ijz, Isetz},

-    [Oeq] = {Icmp, Ijz, Isetz},

-    [One] = {Icmp, Ijnz, Isetnz},

-    [Ogt] = {Icmp, Ijg, Isetg},

-    [Oge] = {Icmp, Ijge, Isetge},

-    [Olt] = {Icmp, Ijl, Isetl},

-    [Ole] = {Icmp, Ijle, Isetle}

+    [Olnot] = {Itest, 0, Ijz, Isetz}, /* lnot invalid for floats */

+    [Oeq] = {Icmp, Icomi, Ijz, Isetz},

+    [One] = {Icmp, Icomi, Ijnz, Isetnz},

+    [Ogt] = {Icmp, Icomi, Ijg, Isetg},

+    [Oge] = {Icmp, Icomi, Ijge, Isetge},

+    [Olt] = {Icmp, Icomi, Ijl, Isetl},

+    [Ole] = {Icmp, Icomi, Ijle, Isetle}

 };

 static Mode mode(Node *n)

@@ -221,6 +222,14 @@

         return inr(s, a);

 }

+static int floatcompare(Node *e)

+{

+    if (exprop(e) == Ovar || exprop(e) == Olit)

+        return floatnode(e);

+    assert(e->expr.nargs > 0);

+    return floatnode(e->expr.args[0]);

+}

+

 /* If we're testing equality, etc, it's a bit silly

  * to generate the test, store it to a bite, expand it

  * to the right width, and then test it again. Try to optimize

@@ -236,7 +245,10 @@

     Loc *l1, *l2;

     AsmOp cond, jmp;

-    cond = reloptab[exprop(args[0])].test;

+    if (floatcompare(args[0]))

+        cond = reloptab[exprop(args[0])].fptest;

+    else

+        cond = reloptab[exprop(args[0])].itest;

     jmp = reloptab[exprop(args[0])].jmp;

     /* if we have a cond, we're knocking off the redundant test,

      * and want to eval the children */

@@ -542,7 +554,8 @@

             a = inr(s, selexpr(s, args[0]));

             b = locreg(ModeB);

             r = locreg(mode(n));

-            g(s, reloptab[exprop(n)].test, a, a, NULL);

+            /* lnot only valid for integer-like values */

+            g(s, reloptab[exprop(n)].itest, a, a, NULL);

             g(s, reloptab[exprop(n)].getflag, b, NULL);

             movz(s, b, r);

             break;

@@ -553,7 +566,10 @@

             a = inr(s, a);

             c = locreg(ModeB);

             r = locreg(mode(n));

-            g(s, reloptab[exprop(n)].test, b, a, NULL);

+            if (floatnode(args[0]))

+                g(s, reloptab[exprop(n)].fptest, b, a, NULL);

+            else

+                g(s, reloptab[exprop(n)].itest, b, a, NULL);

             g(s, reloptab[exprop(n)].getflag, c, NULL);

             movz(s, c, r);

             return r;

-- 

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