From: Matt Arsenault <Matthew.Arsenault@amd.com>
Date: Mon, 24 Jun 2019 14:34:40 +0000 (+0000)
Subject: AMDGPU: Cleanup checking when spills need emergency slots
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=3080eb62d6dc4b50872af0343079a55354df21bb;p=llvm

AMDGPU: Cleanup checking when spills need emergency slots

Address fixme, which should no longer be a problem since r363757.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@364182 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Target/AMDGPU/SIFrameLowering.cpp b/lib/Target/AMDGPU/SIFrameLowering.cpp
index 11d41775421..c2880244b66 100644
--- a/lib/Target/AMDGPU/SIFrameLowering.cpp
+++ b/lib/Target/AMDGPU/SIFrameLowering.cpp
@@ -721,10 +721,13 @@ void SIFrameLowering::emitEpilogue(MachineFunction &MF,
   }
 }
 
-static bool allStackObjectsAreDead(const MachineFrameInfo &MFI) {
+// Note SGPRSpill stack IDs should only be used for SGPR spilling to VGPRs, not
+// memory.
+static bool allStackObjectsAreDeadOrSGPR(const MachineFrameInfo &MFI) {
   for (int I = MFI.getObjectIndexBegin(), E = MFI.getObjectIndexEnd();
        I != E; ++I) {
-    if (!MFI.isDeadObjectIndex(I))
+    if (!MFI.isDeadObjectIndex(I) &&
+        MFI.getStackID(I) != TargetStackID::SGPRSpill)
       return false;
   }
 
@@ -786,11 +789,7 @@ void SIFrameLowering::processFunctionBeforeFrameFinalized(
 
   FuncInfo->removeSGPRToVGPRFrameIndices(MFI);
 
-  // FIXME: The other checks should be redundant with allStackObjectsAreDead,
-  // but currently hasNonSpillStackObjects is set only from source
-  // allocas. Stack temps produced from legalization are not counted currently.
-  if (FuncInfo->hasNonSpillStackObjects() || FuncInfo->hasSpilledVGPRs() ||
-      !AllSGPRSpilledToVGPRs || !allStackObjectsAreDead(MFI)) {
+  if (!allStackObjectsAreDeadOrSGPR(MFI)) {
     assert(RS && "RegScavenger required if spilling");
 
     if (FuncInfo->isEntryFunction()) {