[PATCH] D27639: AMDGPU: Fix AMDGPUPromoteAlloca breaking addrspacecasts

[Matt Arsenault via Phabricator via llvm-commits]

arsenm created this revision.
arsenm added a subscriber: llvm-commits.
Herald added a reviewer: tstellarAMD.
Herald added subscribers: tony-tye, yaxunl, nhaehnle, wdng, kzhuravl.

The users of the addrspacecast were having their types incorrectly
changed, producing invalid bitcasts between address spaces.


https://reviews.llvm.org/D27639

Files:
  lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp
  test/CodeGen/AMDGPU/promote-alloca-addrspacecast.ll


Index: test/CodeGen/AMDGPU/promote-alloca-addrspacecast.ll
===================================================================
--- /dev/null
+++ test/CodeGen/AMDGPU/promote-alloca-addrspacecast.ll
@@ -0,0 +1,21 @@
+; RUN: opt -S -mtriple=amdgcn-unknown-amdhsa -mcpu=kaveri -amdgpu-promote-alloca < %s | FileCheck %s
+
+; The types of the users of the addrspacecast should not be changed.
+
+; CHECK-LABEL: @invalid_bitcast_addrspace(
+; CHECK: getelementptr inbounds [256 x [1 x i32]], [256 x [1 x i32]] addrspace(3)* @invalid_bitcast_addrspace.data, i32 0, i32 %14
+; CHECK: bitcast [1 x i32] addrspace(3)* %{{[0-9]+}} to half addrspace(3)*
+; CHECK: addrspacecast half addrspace(3)* %{{[0-9]+}} to half addrspace(4)*
+; CHECK: bitcast half addrspace(4)* %{{[0-9]+}} to <2 x i16> addrspace(4)*
+define amdgpu_kernel void @invalid_bitcast_addrspace() #0 {
+entry:
+  %data = alloca [1 x i32], align 4
+  %0 = bitcast [1 x i32]* %data to half*
+  %1 = addrspacecast half* %0 to half addrspace(4)*
+  %2 = bitcast half addrspace(4)* %1 to <2 x i16> addrspace(4)*
+  %3 = load <2 x i16>, <2 x i16> addrspace(4)* %2, align 2
+  %4 = bitcast <2 x i16> %3 to <2 x half>
+  ret void
+}
+
+attributes #0 = { nounwind }
Index: lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp
===================================================================
--- lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp
+++ lib/Target/AMDGPU/AMDGPUPromoteAlloca.cpp
@@ -579,6 +579,12 @@
       WorkList.push_back(ICmp);
     }
 
+    if (UseInst->getOpcode() == Instruction::AddrSpaceCast) {
+      // Don't collect the users of this.
+      WorkList.push_back(User);
+      continue;
+    }
+
     if (!User->getType()->isPointerTy())
       continue;
 
@@ -739,7 +745,8 @@
         continue;
       }
 
-      // The operand's value should be corrected on its own.
+      // The operand's value should be corrected on its own and we don't want to
+      // touch the users.
       if (isa<AddrSpaceCastInst>(V))
         continue;
 


-------------- next part --------------
A non-text attachment was scrubbed...
Name: D27639.80971.patch
Type: text/x-patch
Size: 1989 bytes
Desc: not available
URL: <http://lists.llvm.org/pipermail/llvm-commits/attachments/20161210/21858e30/attachment-0001.bin>