[llvm] [llubi] Add support for pext/pdep (PR #227803)

[Yingwei Zheng via llvm-commits]

https://github.com/dtcxzyw created https://github.com/llvm/llvm-project/pull/227803

None

>From 7adc3b1722e93134766d6e011d59d2b3603a4660 Mon Sep 17 00:00:00 2001
From: Yingwei Zheng <dtcxzyw2333 at gmail.com>
Date: Thu, 1 Oct 2026 01:49:53 +0800
Subject: [PATCH] [llubi] Add support for pext/pdep

---
 llvm/test/tools/llubi/intr_int_arith.ll | 18 ++++++++++++++++++
 llvm/tools/llubi/lib/Interpreter.cpp    |  8 ++++++++
 2 files changed, 26 insertions(+)

diff --git a/llvm/test/tools/llubi/intr_int_arith.ll b/llvm/test/tools/llubi/intr_int_arith.ll
index a601200a65d82..9d39f87b90198 100644
--- a/llvm/test/tools/llubi/intr_int_arith.ll
+++ b/llvm/test/tools/llubi/intr_int_arith.ll
@@ -31,6 +31,16 @@ define void @main() {
     call i2 @llvm.ucmp.i32(i32 10, i32 poison)
     call <2 x i2> @llvm.ucmp.v2i2.v2i32(<2 x i32> <i32 10, i32 poison>, <2 x i32> <i32 20, i32 10>)
 
+    call i8 @llvm.pext.i8(i8 170, i8 204)
+    call i8 @llvm.pext.i8(i8 -1, i8 170)
+    call i8 @llvm.pext.i8(i8 -1, i8 poison)
+    call <2 x i8> @llvm.pext.v2i8(<2 x i8> <i8 170, i8 -1>, <2 x i8> <i8 204, i8 170>)
+
+    call i8 @llvm.pdep.i8(i8 10, i8 204)
+    call i8 @llvm.pdep.i8(i8 15, i8 170)
+    call i8 @llvm.pdep.i8(i8 15, i8 poison)
+    call <2 x i8> @llvm.pext.v2i8(<2 x i8> <i8 10, i8 15>, <2 x i8> <i8 204, i8 170>)
+
     ret void
 }
 ; CHECK: Entering function: main
@@ -60,5 +70,13 @@ define void @main() {
 ; CHECK-NEXT:   %24 = call i2 @llvm.ucmp.i2.i32(i32 10, i32 10) => i2 0
 ; CHECK-NEXT:   %25 = call i2 @llvm.ucmp.i2.i32(i32 10, i32 poison) => poison
 ; CHECK-NEXT:   %26 = call <2 x i2> @llvm.ucmp.v2i2.v2i32(<2 x i32> <i32 10, i32 poison>, <2 x i32> <i32 20, i32 10>) => { i2 -1, poison }
+; CHECK-NEXT:   %27 = call i8 @llvm.pext.i8(i8 -86, i8 -52) => i8 10
+; CHECK-NEXT:   %28 = call i8 @llvm.pext.i8(i8 -1, i8 -86) => i8 15
+; CHECK-NEXT:   %29 = call i8 @llvm.pext.i8(i8 -1, i8 poison) => poison
+; CHECK-NEXT:   %30 = call <2 x i8> @llvm.pext.v2i8(<2 x i8> <i8 -86, i8 -1>, <2 x i8> <i8 -52, i8 -86>) => { i8 10, i8 15 }
+; CHECK-NEXT:   %31 = call i8 @llvm.pdep.i8(i8 10, i8 -52) => i8 -120
+; CHECK-NEXT:   %32 = call i8 @llvm.pdep.i8(i8 15, i8 -86) => i8 -86
+; CHECK-NEXT:   %33 = call i8 @llvm.pdep.i8(i8 15, i8 poison) => poison
+; CHECK-NEXT:   %34 = call <2 x i8> @llvm.pext.v2i8(<2 x i8> <i8 10, i8 15>, <2 x i8> <i8 -52, i8 -86>) => { i8 2, i8 3 }
 ; CHECK-NEXT:   ret void
 ; CHECK-NEXT: Exiting function: main
diff --git a/llvm/tools/llubi/lib/Interpreter.cpp b/llvm/tools/llubi/lib/Interpreter.cpp
index 3e4b250f4c85c..26cab20c9e4d3 100644
--- a/llvm/tools/llubi/lib/Interpreter.cpp
+++ b/llvm/tools/llubi/lib/Interpreter.cpp
@@ -1358,6 +1358,14 @@ class InstExecutor : public InstVisitor<InstExecutor, void>,
             }
           });
     }
+    case Intrinsic::pdep:
+    case Intrinsic::pext:
+      return visitIntBinOpWithResult(
+          RetTy, Args[0], Args[1],
+          [IID](const APInt &Val, const APInt &Mask) -> AnyValue {
+            return IID == Intrinsic::pdep ? APIntOps::pdep(Val, Mask)
+                                          : APIntOps::pext(Val, Mask);
+          });
     case Intrinsic::vector_reduce_add:
     case Intrinsic::vector_reduce_mul:
     case Intrinsic::vector_reduce_and: