[llvm] AMDGPU: Add debug print to load/store opt for agpr case (PR #155767)

[Matt Arsenault via llvm-commits]

https://github.com/arsenm created https://github.com/llvm/llvm-project/pull/155767

None

>From 7597b95e39f7bc89a8d8825a448c6c2e875078ac Mon Sep 17 00:00:00 2001
From: Matt Arsenault <Matthew.Arsenault at amd.com>
Date: Thu, 28 Aug 2025 15:24:19 +0900
Subject: [PATCH] AMDGPU: Add debug print to load/store opt for agpr case

---
 llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp b/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
index 6f2ea8ad1ff01..263f7127fbf10 100644
--- a/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
+++ b/llvm/lib/Target/AMDGPU/SILoadStoreOptimizer.cpp
@@ -2466,6 +2466,9 @@ SILoadStoreOptimizer::collectMergeableInsts(
       continue;
 
     if (CI.InstClass == DS_WRITE && CI.IsAGPR) {
+      LLVM_DEBUG(
+          dbgs() << "cannot merge ds writes with mixed AGPR and VGPR data\n");
+
       // FIXME: nothing is illegal in a ds_write2 opcode with two AGPR data
       //        operands. However we are reporting that ds_write2 shall have
       //        only VGPR data so that machine copy propagation does not