[llvm] r323369 - [GlobalISel] Don't fall back to FastISel.

[Amara Emerson via llvm-commits]

Author: aemerson
Date: Wed Jan 24 11:59:29 2018
New Revision: 323369

URL: http://llvm.org/viewvc/llvm-project?rev=323369&view=rev
Log:
[GlobalISel] Don't fall back to FastISel.

Apparently checking the pass structure isn't enough to ensure that we don't fall
back to FastISel, as it's set up as part of the SelectionDAGISel.

Added:
    llvm/trunk/test/CodeGen/AArch64/GlobalISel/fallback-nofastisel.ll
Modified:
    llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
    llvm/trunk/lib/CodeGen/TargetPassConfig.cpp

Modified: llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp?rev=323369&r1=323368&r2=323369&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp (original)
+++ llvm/trunk/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp Wed Jan 24 11:59:29 2018
@@ -1380,8 +1380,10 @@ void SelectionDAGISel::SelectAllBasicBlo
   FastISelFailed = false;
   // Initialize the Fast-ISel state, if needed.
   FastISel *FastIS = nullptr;
-  if (TM.Options.EnableFastISel)
+  if (TM.Options.EnableFastISel) {
+    DEBUG(dbgs() << "Enabling fast-isel\n");
     FastIS = TLI->createFastISel(*FuncInfo, LibInfo);
+  }
 
   setupSwiftErrorVals(Fn, TLI, FuncInfo);
 

Modified: llvm/trunk/lib/CodeGen/TargetPassConfig.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/TargetPassConfig.cpp?rev=323369&r1=323368&r2=323369&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/TargetPassConfig.cpp (original)
+++ llvm/trunk/lib/CodeGen/TargetPassConfig.cpp Wed Jan 24 11:59:29 2018
@@ -708,6 +708,8 @@ bool TargetPassConfig::addCoreISelPasses
   if (EnableGlobalISelOption == cl::BOU_TRUE ||
       (EnableGlobalISelOption == cl::BOU_UNSET &&
        TM->Options.EnableGlobalISel && EnableFastISelOption != cl::BOU_TRUE)) {
+    TM->setFastISel(false);
+
     if (addIRTranslator())
       return true;
 

Added: llvm/trunk/test/CodeGen/AArch64/GlobalISel/fallback-nofastisel.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AArch64/GlobalISel/fallback-nofastisel.ll?rev=323369&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/AArch64/GlobalISel/fallback-nofastisel.ll (added)
+++ llvm/trunk/test/CodeGen/AArch64/GlobalISel/fallback-nofastisel.ll Wed Jan 24 11:59:29 2018
@@ -0,0 +1,10 @@
+; RUN: llc -mtriple=aarch64_be-- %s -o /dev/null -debug-only=isel -O0 2>&1 | FileCheck %s
+
+; This test uses big endian in order to force an abort since it's not currently supported for GISel.
+; The purpose is to check that we don't fall back to FastISel. Checking the pass structure is insufficient
+; because the FastISel is set up in the SelectionDAGISel, so it doesn't appear on the pass structure.
+
+; CHECK-NOT: Enabling fast-ise
+define void @empty() {
+  ret void
+}