[InstSimplify] Add tests to show missed bitcast folding opportunities.

InstSimplify doesn't always know how to fold a bitcast of a constant vector.
In particular, the logic in InstSimplify doesn't know how to handle the case
where the constant vector in input contains some undef elements, and the
number of elements is smaller than the number of elements of the bitcast
vector type.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@281332 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/InstSimplify/bitcast-vector-fold.ll b/test/Transforms/InstSimplify/bitcast-vector-fold.ll
index 687834381fac2108fcf3808c7f3eb86c9c00d57d..126aba63ecbec52073b1060742d4b588262a0580 100644 (file)
--- a/test/Transforms/InstSimplify/bitcast-vector-fold.ll
+++ b/test/Transforms/InstSimplify/bitcast-vector-fold.ll
@@ -123,3 +123,147 @@ define <2 x double> @foo6() {
   %cast = bitcast <4 x i32><i32 -1, i32 -1, i32 -1, i32 -1> to <2 x double>
   ret <2 x double> %cast
 }
+
+define <4 x i32> @bitcast_constexpr_4i32_2i64_u2() {
+; CHECK-LABEL: @bitcast_constexpr_4i32_2i64_u2(
+; CHECK-NEXT:    ret <4 x i32> bitcast (<2 x i64> <i64 undef, i64 2> to <4 x i32>)
+;
+  %cast = bitcast <2 x i64><i64 undef, i64 2> to <4 x i32>
+  ret <4 x i32> %cast
+}
+
+define <4 x i32> @bitcast_constexpr_4i32_2i64_1u() {
+; CHECK-LABEL: @bitcast_constexpr_4i32_2i64_1u(
+; CHECK-NEXT:    ret <4 x i32> bitcast (<2 x i64> <i64 1, i64 undef> to <4 x i32>)
+;
+  %cast = bitcast <2 x i64><i64 1, i64 undef> to <4 x i32>
+  ret <4 x i32> %cast
+}
+
+define <4 x i32> @bitcast_constexpr_4i32_2i64() {
+; CHECK-LABEL: @bitcast_constexpr_4i32_2i64(
+; CHECK-NEXT:    ret <4 x i32> bitcast (<2 x i64> <i64 undef, i64 2> to <4 x i32>)
+;
+  %cast = bitcast <2 x i64><i64 undef, i64 2> to <4 x i32>
+  ret <4 x i32> %cast
+}
+
+define <8 x i16> @bitcast_constexpr_8i16_2i64_u2() {
+; CHECK-LABEL: @bitcast_constexpr_8i16_2i64_u2(
+; CHECK-NEXT:    ret <8 x i16> bitcast (<2 x i64> <i64 undef, i64 2> to <8 x i16>)
+;
+  %cast = bitcast <2 x i64><i64 undef, i64 2> to <8 x i16>
+  ret <8 x i16> %cast
+}
+
+define <8 x i16> @bitcast_constexpr_8i16_2i64_1u() {
+; CHECK-LABEL: @bitcast_constexpr_8i16_2i64_1u(
+; CHECK-NEXT:    ret <8 x i16> bitcast (<2 x i64> <i64 1, i64 undef> to <8 x i16>)
+;
+  %cast = bitcast <2 x i64><i64 1, i64 undef> to <8 x i16>
+  ret <8 x i16> %cast
+}
+
+define <8 x i16> @bitcast_constexpr_8i16_2i64_u65536() {
+; CHECK-LABEL: @bitcast_constexpr_8i16_2i64_u65536(
+; CHECK-NEXT:    ret <8 x i16> bitcast (<2 x i64> <i64 undef, i64 65536> to <8 x i16>)
+;
+  %cast = bitcast <2 x i64><i64 undef, i64 65536> to <8 x i16>
+  ret <8 x i16> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_2i64_u2() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_2i64_u2(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<2 x i64> <i64 undef, i64 2> to <16 x i8>)
+;
+  %cast = bitcast <2 x i64><i64 undef, i64 2> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_2i64_256u() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_2i64_256u(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<2 x i64> <i64 256, i64 undef> to <16 x i8>)
+;
+  %cast = bitcast <2 x i64><i64 256, i64 undef> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_2i64_u256() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_2i64_u256(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<2 x i64> <i64 undef, i64 256> to <16 x i8>)
+;
+  %cast = bitcast <2 x i64><i64 undef, i64 256> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <8 x i16> @bitcast_constexpr_8i16_4i32_uu22() {
+; CHECK-LABEL: @bitcast_constexpr_8i16_4i32_uu22(
+; CHECK-NEXT:    ret <8 x i16> bitcast (<4 x i32> <i32 undef, i32 undef, i32 2, i32 2> to <8 x i16>)
+;
+  %cast = bitcast <4 x i32><i32 undef, i32 undef, i32 2, i32 2> to <8 x i16>
+  ret <8 x i16> %cast
+}
+
+define <8 x i16> @bitcast_constexpr_8i16_4i32_10uu() {
+; CHECK-LABEL: @bitcast_constexpr_8i16_4i32_10uu(
+; CHECK-NEXT:    ret <8 x i16> bitcast (<4 x i32> <i32 1, i32 0, i32 undef, i32 undef> to <8 x i16>)
+;
+  %cast = bitcast <4 x i32><i32 1, i32 0, i32 undef, i32 undef> to <8 x i16>
+  ret <8 x i16> %cast
+}
+
+define <8 x i16> @bitcast_constexpr_8i16_4i32_u257u256() {
+; CHECK-LABEL: @bitcast_constexpr_8i16_4i32_u257u256(
+; CHECK-NEXT:    ret <8 x i16> bitcast (<4 x i32> <i32 undef, i32 65536, i32 undef, i32 65536> to <8 x i16>)
+;
+  %cast = bitcast <4 x i32><i32 undef, i32 65536, i32 undef, i32 65536> to <8 x i16>
+  ret <8 x i16> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_4i32_u2u2() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_4i32_u2u2(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<4 x i32> <i32 undef, i32 2, i32 undef, i32 2> to <16 x i8>)
+;
+  %cast = bitcast <4 x i32><i32 undef, i32 2, i32 undef, i32 2> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_4i32_1u1u() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_4i32_1u1u(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<4 x i32> <i32 1, i32 undef, i32 1, i32 undef> to <16 x i8>)
+;
+  %cast = bitcast <4 x i32><i32 1, i32 undef, i32 1, i32 undef> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_4i32_u256uu() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_4i32_u256uu(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<4 x i32> <i32 undef, i32 256, i32 undef, i32 undef> to <16 x i8>)
+;
+  %cast = bitcast <4 x i32><i32 undef, i32 256, i32 undef, i32 undef> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_8i16_u2u2u2u2() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_8i16_u2u2u2u2(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<8 x i16> <i16 undef, i16 2, i16 undef, i16 2, i16 undef, i16 2, i16 undef, i16 2> to <16 x i8>)
+;
+  %cast = bitcast <8 x i16><i16 undef, i16 2, i16 undef, i16 2, i16 undef, i16 2, i16 undef, i16 2> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_8i16_1u1u1u1u() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_8i16_1u1u1u1u(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<8 x i16> <i16 1, i16 undef, i16 1, i16 undef, i16 1, i16 undef, i16 1, i16 undef> to <16 x i8>)
+;
+  %cast = bitcast <8 x i16><i16 1, i16 undef, i16 1, i16 undef, i16 1, i16 undef, i16 1, i16 undef> to <16 x i8>
+  ret <16 x i8> %cast
+}
+
+define <16 x i8> @bitcast_constexpr_16i8_8i16_u256uuu256uu() {
+; CHECK-LABEL: @bitcast_constexpr_16i8_8i16_u256uuu256uu(
+; CHECK-NEXT:    ret <16 x i8> bitcast (<8 x i16> <i16 undef, i16 256, i16 undef, i16 undef, i16 undef, i16 256, i16 undef, i16 undef> to <16 x i8>)
+;
+  %cast = bitcast <8 x i16><i16 undef, i16 256, i16 undef, i16 undef, i16 undef, i16 256, i16 undef, i16 undef> to <16 x i8>
+  ret <16 x i8> %cast
+}