[llvm] r248591 - AMDGPU: Disable some passes that are not meaningful

[Matt Arsenault via llvm-commits]

Author: arsenm
Date: Fri Sep 25 12:41:20 2015
New Revision: 248591

URL: http://llvm.org/viewvc/llvm-project?rev=248591&view=rev
Log:
AMDGPU: Disable some passes that are not meaningful

Don't run passes related to stack maps, garbage collection,
exceptions since these aren't useful for GPUs.

There might be a few more to turn off that I'm less sure about
(e.g. ShrinkWrapping) or I'm not sure how to disable
(SafeStack and StackProtector)

Modified:
    llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp

Modified: llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp?rev=248591&r1=248590&r2=248591&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp (original)
+++ llvm/trunk/lib/Target/AMDGPU/AMDGPUTargetMachine.cpp Fri Sep 25 12:41:20 2015
@@ -110,7 +110,13 @@ namespace {
 class AMDGPUPassConfig : public TargetPassConfig {
 public:
   AMDGPUPassConfig(TargetMachine *TM, PassManagerBase &PM)
-    : TargetPassConfig(TM, PM) {}
+    : TargetPassConfig(TM, PM) {
+
+    // Exceptions and StackMaps are not supported, so these passes will never do
+    // anything.
+    disablePass(&StackMapLivenessID);
+    disablePass(&FuncletLayoutID);
+  }
 
   AMDGPUTargetMachine &getAMDGPUTargetMachine() const {
     return getTM<AMDGPUTargetMachine>();
@@ -126,8 +132,9 @@ public:
 
   void addIRPasses() override;
   void addCodeGenPrepare() override;
-  virtual bool addPreISel() override;
-  virtual bool addInstSelector() override;
+  bool addPreISel() override;
+  bool addInstSelector() override;
+  bool addGCPasses() override;
 };
 
 class R600PassConfig : public AMDGPUPassConfig {
@@ -200,6 +207,11 @@ bool AMDGPUPassConfig::addInstSelector()
   return false;
 }
 
+bool AMDGPUPassConfig::addGCPasses() {
+  // Do nothing. GC is not supported.
+  return false;
+}
+
 //===----------------------------------------------------------------------===//
 // R600 Pass Setup
 //===----------------------------------------------------------------------===//