[clang] [CIR][NFS] Add test cases for VecShuffle with -1 index (PR #143304)

[Amr Hesham via cfe-commits]

https://github.com/AmrDeveloper created https://github.com/llvm/llvm-project/pull/143304

Add a test case for __builtin_shufflevector with -1 index, it was useful in the incubator to catch an issue in the folder 

>From c6d78b93437bf1145972146f189a3c0a39e20219 Mon Sep 17 00:00:00 2001
From: AmrDeveloper <amr96 at programmer.net>
Date: Sun, 8 Jun 2025 12:57:10 +0200
Subject: [PATCH] [CIR][NFS] Add test cases for VecShuffle with -1 index

---
 clang/test/CIR/CodeGen/vector-ext.cpp | 25 +++++++++++++++++++++++++
 clang/test/CIR/CodeGen/vector.cpp     | 25 +++++++++++++++++++++++++
 2 files changed, 50 insertions(+)

diff --git a/clang/test/CIR/CodeGen/vector-ext.cpp b/clang/test/CIR/CodeGen/vector-ext.cpp
index aa836c2e70a12..e1814f216f6b9 100644
--- a/clang/test/CIR/CodeGen/vector-ext.cpp
+++ b/clang/test/CIR/CodeGen/vector-ext.cpp
@@ -1116,3 +1116,28 @@ void foo19() {
 // OGCG: %[[TMP_A:.*]] = load <4 x i32>, ptr %[[VEC_A]], align 16
 // OGCG: %[[TMP_B:.*]] = load <4 x i32>, ptr %[[VEC_B]], align 16
 // OGCG: %[[SHUF:.*]] = shufflevector <4 x i32> %[[TMP_A]], <4 x i32> %[[TMP_B]], <4 x i32> <i32 7, i32 5, i32 3, i32 1>
+
+void foo20() {
+  vi4 a;
+  vi4 b;
+  vi4 u = __builtin_shufflevector(a, b, -1, 1, -1, 1);
+}
+
+// CIR: %[[VEC_A:.*]] = cir.alloca !cir.vector<4 x !s32i>, !cir.ptr<!cir.vector<4 x !s32i>>, ["a"]
+// CIR: %[[VEC_B:.*]] = cir.alloca !cir.vector<4 x !s32i>, !cir.ptr<!cir.vector<4 x !s32i>>, ["b"]
+// CIR: %[[TMP_A:.*]] = cir.load{{.*}} %[[VEC_A]] : !cir.ptr<!cir.vector<4 x !s32i>>, !cir.vector<4 x !s32i>
+// CIR: %[[TMP_B:.*]] = cir.load{{.*}} %[[VEC_B]] : !cir.ptr<!cir.vector<4 x !s32i>>, !cir.vector<4 x !s32i>
+// CIR: %[[SHUF:.*]] = cir.vec.shuffle(%[[TMP_A]], %[[TMP_B]] : !cir.vector<4 x !s32i>) [#cir.int<-1> :
+// CIR-SAME: !s64i, #cir.int<1> : !s64i, #cir.int<-1> : !s64i, #cir.int<1> : !s64i] : !cir.vector<4 x !s32i>
+
+// LLVM: %[[VEC_A:.*]] = alloca <4 x i32>, i64 1, align 16
+// LLVM: %[[VEC_B:.*]] = alloca <4 x i32>, i64 1, align 16
+// LLVM: %[[TMP_A:.*]] = load <4 x i32>, ptr %[[VEC_A]], align 16
+// LLVM: %[[TMP_B:.*]] = load <4 x i32>, ptr %[[VEC_B]], align 16
+// LLVM: %[[SHUF:.*]] = shufflevector <4 x i32> %[[TMP_A]], <4 x i32> %[[TMP_B]], <4 x i32> <i32 poison, i32 1, i32 poison, i32 1>
+
+// OGCG: %[[VEC_A:.*]] = alloca <4 x i32>, align 16
+// OGCG: %[[VEC_B:.*]] = alloca <4 x i32>, align 16
+// OGCG: %[[TMP_A:.*]] = load <4 x i32>, ptr %[[VEC_A]], align 16
+// OGCG: %[[TMP_B:.*]] = load <4 x i32>, ptr %[[VEC_B]], align 16
+// OGCG: %[[SHUF:.*]] = shufflevector <4 x i32> %[[TMP_A]], <4 x i32> %[[TMP_B]], <4 x i32> <i32 poison, i32 1, i32 poison, i32 1>
diff --git a/clang/test/CIR/CodeGen/vector.cpp b/clang/test/CIR/CodeGen/vector.cpp
index f53264c584cc0..4f116faa7a1ac 100644
--- a/clang/test/CIR/CodeGen/vector.cpp
+++ b/clang/test/CIR/CodeGen/vector.cpp
@@ -1150,3 +1150,28 @@ void foo22() {
 
 // OGCG: %[[VEC_COND:.*]] = icmp ne <4 x i32> {{.*}}, zeroinitializer
 // OGCG: %[[RES:.*]] = select <4 x i1> %[[VEC_COND]], <4 x float> {{.*}}, <4 x float> {{.*}}
+
+void foo23() {
+  vi4 a;
+  vi4 b;
+  vi4 u = __builtin_shufflevector(a, b, -1, 1, -1, 1);
+}
+
+// CIR: %[[VEC_A:.*]] = cir.alloca !cir.vector<4 x !s32i>, !cir.ptr<!cir.vector<4 x !s32i>>, ["a"]
+// CIR: %[[VEC_B:.*]] = cir.alloca !cir.vector<4 x !s32i>, !cir.ptr<!cir.vector<4 x !s32i>>, ["b"]
+// CIR: %[[TMP_A:.*]] = cir.load{{.*}} %[[VEC_A]] : !cir.ptr<!cir.vector<4 x !s32i>>, !cir.vector<4 x !s32i>
+// CIR: %[[TMP_B:.*]] = cir.load{{.*}} %[[VEC_B]] : !cir.ptr<!cir.vector<4 x !s32i>>, !cir.vector<4 x !s32i>
+// CIR: %[[SHUF:.*]] = cir.vec.shuffle(%[[TMP_A]], %[[TMP_B]] : !cir.vector<4 x !s32i>) [#cir.int<-1> :
+// CIR-SAME: !s64i, #cir.int<1> : !s64i, #cir.int<-1> : !s64i, #cir.int<1> : !s64i] : !cir.vector<4 x !s32i>
+
+// LLVM: %[[VEC_A:.*]] = alloca <4 x i32>, i64 1, align 16
+// LLVM: %[[VEC_B:.*]] = alloca <4 x i32>, i64 1, align 16
+// LLVM: %[[TMP_A:.*]] = load <4 x i32>, ptr %[[VEC_A]], align 16
+// LLVM: %[[TMP_B:.*]] = load <4 x i32>, ptr %[[VEC_B]], align 16
+// LLVM: %[[SHUF:.*]] = shufflevector <4 x i32> %[[TMP_A]], <4 x i32> %[[TMP_B]], <4 x i32> <i32 poison, i32 1, i32 poison, i32 1>
+
+// OGCG: %[[VEC_A:.*]] = alloca <4 x i32>, align 16
+// OGCG: %[[VEC_B:.*]] = alloca <4 x i32>, align 16
+// OGCG: %[[TMP_A:.*]] = load <4 x i32>, ptr %[[VEC_A]], align 16
+// OGCG: %[[TMP_B:.*]] = load <4 x i32>, ptr %[[VEC_B]], align 16
+// OGCG: %[[SHUF:.*]] = shufflevector <4 x i32> %[[TMP_A]], <4 x i32> %[[TMP_B]], <4 x i32> <i32 poison, i32 1, i32 poison, i32 1>