NFC; add an example that subtracts pointers to two global vars

llvm · Jul 26, 2020 · 02dadab · 02dadab
1 parent b1210c0
commit 02dadab
Showing 1 changed file with 13 additions and 2 deletions.
diff --git a/llvm/test/Transforms/InstSimplify/freeze.ll b/llvm/test/Transforms/InstSimplify/freeze.ll
@@ -111,8 +111,7 @@ define <2 x float> @constvector_FP_noopt() {
 }
 
 @g = external global i16, align 1
-
-; Negative test
+@g2 = external global i16, align 1
 
 define float @constant_expr() {
 ; CHECK-LABEL: @constant_expr(
@@ -138,6 +137,18 @@ define i32* @constant_expr3() {
   ret i32* %r
 }
 
+define i64 @ptrdiff() {
+; CHECK-LABEL: @ptrdiff(
+; CHECK-NEXT:    [[R:%.*]] = freeze i64 sub (i64 ptrtoint (i16* @g to i64), i64 ptrtoint (i16* @g2 to i64))
+; CHECK-NEXT:    ret i64 [[R]]
+;
+  %i = ptrtoint i16* @g to i64
+  %i2 = ptrtoint i16* @g2 to i64
+  %diff = sub i64 %i, %i2
+  %r = freeze i64 %diff
+  ret i64 %r
+}
+
 ; Negative test
 
 define <2 x i31> @vector_element_constant_expr() {