[llvm] [SPIRV] Error for zero-length arrays if not a shader (PR #169732)

[Nick Sarnie via llvm-commits]

https://github.com/sarnex updated https://github.com/llvm/llvm-project/pull/169732

>From 7c4cc9e20cb5fb25678dc612feb2388361b7ac83 Mon Sep 17 00:00:00 2001
From: Nick Sarnie <nick.sarnie at intel.com>
Date: Wed, 26 Nov 2025 13:36:51 -0800
Subject: [PATCH] [SPIRV] Error for zero-length arrays if not a shader

Signed-off-by: Nick Sarnie <nick.sarnie at intel.com>
---
 llvm/lib/Target/SPIRV/SPIRVGlobalRegistry.cpp | 13 +++++++++----
 llvm/test/CodeGen/SPIRV/zero-length-array.ll  | 10 ++++++++--
 2 files changed, 17 insertions(+), 6 deletions(-)

diff --git a/llvm/lib/Target/SPIRV/SPIRVGlobalRegistry.cpp b/llvm/lib/Target/SPIRV/SPIRVGlobalRegistry.cpp
index 0b89e5f4cf316..17af251e20929 100644
--- a/llvm/lib/Target/SPIRV/SPIRVGlobalRegistry.cpp
+++ b/llvm/lib/Target/SPIRV/SPIRVGlobalRegistry.cpp
@@ -883,10 +883,15 @@ SPIRVType *SPIRVGlobalRegistry::getOpTypeArray(uint32_t NumElems,
           .addUse(NumElementsVReg);
     });
   } else {
-    assert(ST.isShader() && "Runtime arrays are not allowed in non-shader "
-                            "SPIR-V modules.");
-    if (!ST.isShader())
-      return nullptr;
+    if (!ST.isShader()) {
+      Function &Fn = MIRBuilder.getMF().getFunction();
+      Fn.getContext().diagnose(DiagnosticInfoUnsupported(
+          Fn,
+          "Runtime arrays are not allowed in non-shader "
+          "SPIR-V modules",
+          MIRBuilder.getDebugLoc()));
+      return ElemType;
+    }
     ArrayType = createOpType(MIRBuilder, [&](MachineIRBuilder &MIRBuilder) {
       return MIRBuilder.buildInstr(SPIRV::OpTypeRuntimeArray)
           .addDef(createTypeVReg(MIRBuilder))
diff --git a/llvm/test/CodeGen/SPIRV/zero-length-array.ll b/llvm/test/CodeGen/SPIRV/zero-length-array.ll
index 5fd94d25dfd87..ab3647bb17fa2 100644
--- a/llvm/test/CodeGen/SPIRV/zero-length-array.ll
+++ b/llvm/test/CodeGen/SPIRV/zero-length-array.ll
@@ -1,7 +1,9 @@
-; RUN: llc -verify-machineinstrs -O0 -mtriple=spirv-unknown-vulkan-compute %s -o - | FileCheck %s
+; RUN: llc -verify-machineinstrs -O0 -mtriple=spirv-unknown-vulkan-compute < %s | FileCheck %s
 ; RUN: %if spirv-tools %{ llc -O0 -mtriple=spirv-unknown-vulkan-compute %s -o - -filetype=obj | spirv-val %}
 
-; Nothing is generated, but compilation doesn't crash.
+; RUN: not llc -verify-machineinstrs -O0 -mtriple=spirv64-unknown-unknown < %s 2>&1 | FileCheck -check-prefix=CHECK-ERR %s
+
+; For compute, nothing is generated, but compilation doesn't crash.
 ; CHECK: OpName %[[#FOO:]] "foo"
 ; CHECK: OpName %[[#RTM:]] "reg2mem alloca point"
 ; CHECK: %[[#INT:]] = OpTypeInt 32 0
@@ -11,6 +13,10 @@
 ; CHECK-NEXT: OpReturn
 ; CHECK-NEXT: OpFunctionEnd
 
+
+; For non-compute, error.
+; CHECK-ERR: in function foo void (): Runtime arrays are not allowed in non-shader SPIR-V modules
+
 define spir_func void @foo() {
 entry:
   %i = alloca [0 x i32], align 4