test for a variety of new transformations:

* A & ~A == 0
  * A / (2^c) == A >> c  if unsigned
  * 0 / A == 0
  * 1.0 * A == A
  * A * (2^c) == A << c
  * A ^ ~A == -1
  * A | ~A == -1
  * 0 % X = 0
  * A % (2^c) == A & (c-1) if unsigned
  * A - (A & B) == A & ~B
  * -1 - A == ~A


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5588 91177308-0d34-0410-b5e6-96231b3b80d8

test/Transforms/InstCombine/and.ll

@@ -38,3 +38,8 @@ bool %test6(bool %A) {
 	ret bool %B
 }
 
+int %test7(int %A) {         ; A & ~A == 0
+        %NotA = xor int %A, -1
+        %B = and int %A, %NotA
+        ret int %B
+}

test/Transforms/InstCombine/div.ll

@@ -12,3 +12,13 @@ int %test1(int %A) {
 	%B = div int %A, 1
 	ret int %B
 }
+
+uint %test2(uint %A) {
+	%B = div uint %A, 8   ; => Shift
+	ret int %B
+}
+
+int %test3(int %A) {
+	%B = div int 0, %A    ; => 0, don't need to keep traps
+	ret int %B
+}

test/Transforms/InstCombine/mul.ll

@@ -26,3 +26,12 @@ begin
 	ret int %B
 end
 
+double %test4(double %A) {
+	%B = mul double 1.0, %A   ; This is safe for FP
+	ret double %B
+}
+
+int %test5(int %A) {
+	%B = mul int %A, 8
+	ret int %B
+}

test/Transforms/InstCombine/or.ll

@@ -58,3 +58,14 @@ int %test10(int %A) {
 	ret int %B
 }
 
+int %test11(int %A) {    ; A ^ ~A == -1
+        %NotA = xor int -1, %A
+        %B = xor int %A, %NotA
+        ret int %B
+}
+
+int %test12(int %A) {    ; A | ~A == -1
+        %NotA = xor int -1, %A
+        %B = or int %A, %NotA
+        ret int %B
+}

test/Transforms/InstCombine/rem.ll

@@ -8,8 +8,17 @@
 
 implementation
 
-int "test1"(int %A) {
+int %test1(int %A) {
 	%B = rem int %A, 1    ; ISA constant 0
 	ret int %B
 }
 
+int %test2(int %A) {          ; 0 % X = 0, we don't need ot preserve traps
+	%B = rem int 0, %A
+	ret int %B
+}
+
+uint %test3(uint %A) {
+	%B = rem uint %A, 8   ; & 7
+	ret uint %B
+}

test/Transforms/InstCombine/sub.ll

@@ -35,3 +35,15 @@ int "test5"(int %A, int %Bok, int %Cok) {
 	%E = sub int %A, %D
 	ret int %E
 }
+
+int %test6(int %A, int %B) {
+	%C = and int %A, %B   ; A - (A & B) => A & ~B
+	%D = sub int %A, %C
+	ret int %D
+}
+
+int %test7(int %A) {
+	%B = sub int -1, %A   ; B = ~A
+	ret int %B
+}
+