Add tests for bitcast-bitcast sequences for all scalar/vector permutations

As noted in http://reviews.llvm.org/D15392 , we should be able to improve this.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@255370 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/test/Transforms/InstCombine/bitcast-bitcast.ll b/test/Transforms/InstCombine/bitcast-bitcast.ll
new file mode 100644 (file)
index 0000000..a67666c
--- /dev/null
+++ b/test/Transforms/InstCombine/bitcast-bitcast.ll
@@ -0,0 +1,90 @@
+; RUN: opt < %s -instcombine -S | FileCheck %s
+
+; Check all scalar / vector combinations for a pair of bitcasts.
+
+define ppc_fp128 @bitcast_bitcast_s_s_s(i128 %a) {
+  %bc1 = bitcast i128 %a to fp128
+  %bc2 = bitcast fp128 %bc1 to ppc_fp128
+  ret ppc_fp128 %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_s_s_s(
+; CHECK-NEXT:  %bc2 = bitcast i128 %a to ppc_fp128
+; CHECK-NEXT:  ret ppc_fp128 %bc2
+}
+
+define <2 x i32> @bitcast_bitcast_s_s_v(i64 %a) {
+  %bc1 = bitcast i64 %a to double
+  %bc2 = bitcast double %bc1 to <2 x i32>
+  ret <2 x i32> %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_s_s_v(
+; CHECK-NEXT:  %bc1 = bitcast i64 %a to double
+; CHECK-NEXT:  %bc2 = bitcast double %bc1 to <2 x i32>
+; CHECK-NEXT:  ret <2 x i32> %bc2
+}
+
+define double @bitcast_bitcast_s_v_s(i64 %a) {
+  %bc1 = bitcast i64 %a to <2 x i32>
+  %bc2 = bitcast <2 x i32> %bc1 to double
+  ret double %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_s_v_s(
+; CHECK-NEXT:  %bc1 = bitcast i64 %a to <2 x i32>
+; CHECK-NEXT:  %bc2 = bitcast <2 x i32> %bc1 to double
+; CHECK-NEXT:  ret double %bc2
+}
+
+define <2 x i32> @bitcast_bitcast_s_v_v(i64 %a) {
+  %bc1 = bitcast i64 %a to <4 x i16>
+  %bc2 = bitcast <4 x i16> %bc1 to <2 x i32>
+  ret <2 x i32> %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_s_v_v(
+; CHECK-NEXT:  %bc1 = bitcast i64 %a to <4 x i16>
+; CHECK-NEXT:  %bc2 = bitcast <4 x i16> %bc1 to <2 x i32>
+; CHECK-NEXT:  ret <2 x i32> %bc2
+}
+
+define i64 @bitcast_bitcast_v_s_s(<2 x i32> %a) {
+  %bc1 = bitcast <2 x i32> %a to double
+  %bc2 = bitcast double %bc1 to i64
+  ret i64 %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_v_s_s(
+; CHECK-NEXT:  %bc1 = bitcast <2 x i32> %a to double
+; CHECK-NEXT:  %bc2 = bitcast double %bc1 to i64
+; CHECK-NEXT:  ret i64 %bc2
+}
+
+define <4 x i16> @bitcast_bitcast_v_s_v(<2 x i32> %a) {
+  %bc1 = bitcast <2 x i32> %a to double
+  %bc2 = bitcast double %bc1 to <4 x i16>
+  ret <4 x i16> %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_v_s_v(
+; CHECK-NEXT:  %bc1 = bitcast <2 x i32> %a to double
+; CHECK-NEXT:  %bc2 = bitcast double %bc1 to <4 x i16>
+; CHECK-NEXT:  ret <4 x i16> %bc2
+}
+
+define double @bitcast_bitcast_v_v_s(<2 x float> %a) {
+  %bc1 = bitcast <2 x float> %a to <4 x i16>
+  %bc2 = bitcast <4 x i16> %bc1 to double
+  ret double %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_v_v_s(
+; CHECK-NEXT:  %bc1 = bitcast <2 x float> %a to <4 x i16>
+; CHECK-NEXT:  %bc2 = bitcast <4 x i16> %bc1 to double
+; CHECK-NEXT:  ret double %bc2
+}
+
+define <2 x i32> @bitcast_bitcast_v_v_v(<2 x float> %a) {
+  %bc1 = bitcast <2 x float> %a to <4 x i16>
+  %bc2 = bitcast <4 x i16> %bc1 to <2 x i32>
+  ret <2 x i32> %bc2
+
+; CHECK-LABEL: @bitcast_bitcast_v_v_v(
+; CHECK-NEXT:  %bc2 = bitcast <2 x float> %a to <2 x i32>
+; CHECK-NEXT:  ret <2 x i32> %bc2
+}
+