Merge pull request #146 from shattered/_a2dcf481

pdp11: use bit test insn when possible.  cowasm: don't add extra padd…

src/cowasm/cowasm.coh

@@ -868,6 +868,10 @@ sub AlignCb implements SymbolCallback is
         SimpleError("alignment must be a power of two");
     end if;
 
+    if [currentProgramCounter] & (tokenNumber - 1) == 0 then
+        return;
+    end if;
+
     var newpc := ([currentProgramCounter] + tokenNumber) & ~(tokenNumber - 1);
     while [currentProgramCounter] != newpc loop
         Emit8(0);

src/cowbe/archpdp11.cow.ng

@@ -1338,7 +1338,6 @@ gen r32 := SUB4($$, r32:rhs)
 }
 gen r32 := SUB4($$, CONSTANT():c)     { E_subi4($c.value, $$); }
 
-// XXX use BIT when BEQx(ANDx())
 gen r8  := AND1($$, r8:rhs) uses r5b  { E_and($rhs, $$); }
 gen r8  := AND1($$, CONSTANT():c)     { E_andi($c.value, $$); }
 gen r16 := AND2($$, r16:rhs) uses r5  { E_and($rhs, $$); }
@@ -1468,8 +1467,20 @@ gen BEQ0(CONSTANT():c1, CONSTANT():c2):b uses all { beqc(self.n[0], $c1.value, $
 
 gen BEQ1(r8:lhs, r8:rhs):b         uses all { E_cmp($lhs, $rhs);      CmpJumpsJe(self.n[0]); }
 gen BEQ1(r8:lhs, CONSTANT():c):b   uses all { if ($c.value == 0) then E_tst($lhs); else E_cmpi($c.value, $lhs); end if; CmpJumpsJe(self.n[0]); }
+gen BEQ1(AND1(r8:lhs, r8:rhs), CONSTANT(value==0)):b { E_alu2("BIT", $rhs, $lhs); CmpJumpsJe(self.n[0]); }
+gen BEQ1(AND1(r8:lhs, CONSTANT(value!=0):c), CONSTANT(value==0)):b
+{
+	E_alu2i("BIT", $c.value, $lhs);
+	CmpJumpsJe(self.n[0]);
+}
 gen BEQ2(r16:lhs, r16:rhs):b       uses all { E_cmp($lhs, $rhs);      CmpJumpsJe(self.n[0]); }
 gen BEQ2(r16:lhs, CONSTANT():c):b  uses all { if ($c.value == 0) then E_tst($lhs); else E_cmpi($c.value, $lhs); end if; CmpJumpsJe(self.n[0]); }
+gen BEQ2(AND2(r16:lhs, r16:rhs), CONSTANT(value==0)):b { E_alu2("BIT", $rhs, $lhs); CmpJumpsJe(self.n[0]); }
+gen BEQ2(AND2(r16:lhs, CONSTANT(value!=0):c), CONSTANT(value==0)):b
+{
+	E_alu2i("BIT", $c.value, $lhs);
+	CmpJumpsJe(self.n[0]);
+}
 gen BEQ4(r32:lhs, r32:rhs):b       uses all { E_cmpeq4($lhs, $rhs);   CmpJumpsJe(self.n[0]); }
 //n BEQ4(r32:lhs, CONSTANT():c):b  uses all { E_cmpi4($c.value, $lhs); CmpJumpsJe(self.n[0]); } // XXX deadlock
 

tests/logic-16bit.good

@@ -1,5 +1,7 @@
 two|one==three: yes
 three&two==two: yes
+two&one==ZERO: yes
+two&ONE==ZERO: yes
 two^one==three: yes
 three^one==two: yes
 ~zero==mone: yes

tests/logic-16bit.test.cow

@@ -9,9 +9,13 @@ var three: uint16 := 0x3003;
 var four: uint16 := 0x4004;
 
 const NOTFOUR := ~0x4004;
+const ZERO := 0;
+const ONE := 0x1001;
 
 print("two|one==three"); if (two|one) == three then yes(); else no(); end if;
 print("three&two==two"); if (three&two) == two then yes(); else no(); end if;
+print("two&one==ZERO");  if (two&one) == ZERO  then yes(); else no(); end if;
+print("two&ONE==ZERO");  if (two&ONE) == ZERO  then yes(); else no(); end if;
 print("two^one==three"); if (two^one) == three then yes(); else no(); end if;
 print("three^one==two"); if (three^one) == two then yes(); else no(); end if;
 print("~zero==mone");    if ~zero == mone      then yes(); else no(); end if;

tests/logic-8bit.good

@@ -1,5 +1,7 @@
 two|one==three: yes
 three&two==two: yes
+two&one==ZERO: yes
+two&ONE==ZERO: yes
 two^one==three: yes
 three^one==two: yes
 ~zero==mone: yes

tests/logic-8bit.test.cow

@@ -9,9 +9,13 @@ var three: int8 := 3;
 var four: int8 := 4;
 
 const NOTFOUR := ~4;
+const ZERO := 0;
+const ONE := 1;
 
 print("two|one==three"); if (two|one) == three then yes(); else no(); end if;
 print("three&two==two"); if (three&two) == two then yes(); else no(); end if;
+print("two&one==ZERO");  if (two&one) == ZERO  then yes(); else no(); end if;
+print("two&ONE==ZERO");  if (two&ONE) == ZERO  then yes(); else no(); end if;
 print("two^one==three"); if (two^one) == three then yes(); else no(); end if;
 print("three^one==two"); if (three^one) == two then yes(); else no(); end if;
 print("~zero==mone");    if ~zero == mone      then yes(); else no(); end if;