LoopVectorize: Vectorize all accesses in address space zero with unit stride

[oota-llvm.git] / test / Transforms / InstSimplify / compare.ll

diff --git a/test/Transforms/InstSimplify/compare.ll b/test/Transforms/InstSimplify/compare.ll
index 56627b99a476c709dc7b395d22adbdb672f9c2f7..82d56028c37a617ddeacda0c5c277dd9ec43d40e 100644 (file)
--- a/test/Transforms/InstSimplify/compare.ll
+++ b/test/Transforms/InstSimplify/compare.ll
@@ -357,6 +357,14 @@ define i1 @lshr2(i32 %x) {
 ; CHECK: ret i1 false
 }
 
+define i1 @lshr3(i32 %x) {
+; CHECK: @lshr3
+  %s = lshr i32 %x, %x
+  %c = icmp eq i32 %s, 0
+  ret i1 %c
+; CHECK: ret i1 true
+}
+
 define i1 @ashr1(i32 %x) {
 ; CHECK: @ashr1
   %s = ashr i32 -1, %x
@@ -373,6 +381,14 @@ define i1 @ashr2(i32 %x) {
 ; CHECK: ret i1 false
 }
 
+define i1 @ashr3(i32 %x) {
+; CHECK: @ashr3
+  %s = ashr i32 %x, %x
+  %c = icmp eq i32 %s, 0
+  ret i1 %c
+; CHECK: ret i1 true
+}
+
 define i1 @select1(i1 %cond) {
 ; CHECK: @select1
   %s = select i1 %cond, i32 1, i32 0
@@ -647,3 +663,49 @@ unreachableblock:
   %Y = icmp eq i32* %X, null
   ret i1 %Y
 }
+
+; It's not valid to fold a comparison of an argument with an alloca, even though
+; that's tempting. An argument can't *alias* an alloca, however the aliasing rule
+; relies on restrictions against guessing an object's address and dereferencing.
+; There are no restrictions against guessing an object's address and comparing.
+
+define i1 @alloca_argument_compare(i64* %arg) {
+  %alloc = alloca i64
+  %cmp = icmp eq i64* %arg, %alloc
+  ret i1 %cmp
+  ; CHECK: alloca_argument_compare
+  ; CHECK: ret i1 %cmp
+}
+
+; As above, but with the operands reversed.
+
+define i1 @alloca_argument_compare_swapped(i64* %arg) {
+  %alloc = alloca i64
+  %cmp = icmp eq i64* %alloc, %arg
+  ret i1 %cmp
+  ; CHECK: alloca_argument_compare_swapped
+  ; CHECK: ret i1 %cmp
+}
+
+; Don't assume that a noalias argument isn't equal to a global variable's
+; address. This is an example where AliasAnalysis' NoAlias concept is
+; different from actual pointer inequality.
+
+@y = external global i32
+define zeroext i1 @external_compare(i32* noalias %x) {
+  %cmp = icmp eq i32* %x, @y
+  ret i1 %cmp
+  ; CHECK: external_compare
+  ; CHECK: ret i1 %cmp
+}
+
+define i1 @alloca_gep(i64 %a, i64 %b) {
+; CHECK: @alloca_gep
+; We can prove this GEP is non-null because it is inbounds and the pointer
+; is non-null.
+  %strs = alloca [1000 x [1001 x i8]], align 16
+  %x = getelementptr inbounds [1000 x [1001 x i8]]* %strs, i64 0, i64 %a, i64 %b
+  %cmp = icmp eq i8* %x, null
+  ret i1 %cmp
+; CHECK-NEXT: ret i1 false
+}