[AMDGPU] Remove exit-on-error in test (PR27761)

[rovka]

Summary

The exit-on-error flag was necessary in order to avoid an assertion when handling DYNAMIC_STACKALLOC nodes in SelectionDAGLegalize.

We can avoid the assertion by creating some dummy nodes. This enables us to remove the exit-on-error flag on the first 2 run lines (SI), but on the third run line (R600) we would run into another assertion when trying to reserve indirect registers. This patch also replaces that assertion with an early exit from the function.

Fixes PR27761.

Last exit-on-error patch for AMDGPU

[rovka]

Update some tests that I initially forgot about.

[rovka]

...with the initial changes too, ofc.

[arsenm]

lib/Target/AMDGPU/AMDGPUISelLowering.cpp

692

I would prefer not using getIntPtrConstant since I would like to remove it in general from LLVM. This would more preferrably be getConstant(-1, Op.getValueType())

test/CodeGen/AMDGPU/promote-alloca-bitcast-function.ll

9

I think this can now have a check for the second function's error

[rovka]

Using the -1 constant causes some assertions later on, but 0 works like a charm.
Updated the test, too.
Thanks.

[rovka]

Ping?

[arsenm]

LGTM

test/CodeGen/AMDGPU/private-memory-broken.ll

1–2

Can you remove the -mcpu=SI? I've been removing them from tests as they get touched

[rovka]

test/CodeGen/AMDGPU/private-memory-broken.ll

1–2

Will do, thanks.

lib/Target/AMDGPU/AMDGPUISelLowering.cpp

 
 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
                                                       SelectionDAG &DAG) const {
   const Function &Fn = *DAG.getMachineFunction().getFunction();
 
   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
                                             SDLoc(Op).getDebugLoc());
   DAG.getContext()->diagnose(NoDynamicAlloca);
-  return SDValue();
+  auto Ops = {DAG.getIntPtrConstant(0, SDLoc()), Op.getOperand(0)};
+  return DAG.getMergeValues(Ops, SDLoc());
 }
 
 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
                                              SelectionDAG &DAG) const {
   switch (Op.getOpcode()) {
   default:
     Op->dump(&DAG);
     llvm_unreachable("Custom lowering code for this"

lib/Target/AMDGPU/AMDGPUInstrInfo.cpp

int AMDGPUInstrInfo::getIndirectIndexBegin(const MachineFunction &MF) const {
   return Offset + 1;
 }
 
 int AMDGPUInstrInfo::getIndirectIndexEnd(const MachineFunction &MF) const {
   int Offset = 0;
   const MachineFrameInfo *MFI = MF.getFrameInfo();
 
   // Variable sized objects are not supported
-  assert(!MFI->hasVarSizedObjects());
+  if (MFI->hasVarSizedObjects()) {
+    return -1;
+  }
 
   if (MFI->getNumObjects() == 0) {
     return -1;
   }
 
   unsigned IgnoredFrameReg;
   Offset = MF.getSubtarget().getFrameLowering()->getFrameIndexReference(
       MF, -1, IgnoredFrameReg);

test/CodeGen/AMDGPU/dynamic_stackalloc.ll

-; RUN: not llc -march=amdgcn -mcpu=tahiti -mattr=+promote-alloca -verify-machineinstrs -exit-on-error < %s 2>&1 | FileCheck %s
-; RUN: not llc -march=amdgcn -mcpu=tahiti -mattr=-promote-alloca -verify-machineinstrs -exit-on-error < %s 2>&1 | FileCheck %s
-; RUN: not llc -march=r600 -mcpu=cypress -exit-on-error < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=amdgcn -mcpu=tahiti -mattr=+promote-alloca -verify-machineinstrs < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=amdgcn -mcpu=tahiti -mattr=-promote-alloca -verify-machineinstrs < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=r600 -mcpu=cypress < %s 2>&1 | FileCheck %s
 
 ; CHECK: in function test_dynamic_stackalloc{{.*}}: unsupported dynamic alloca
 
 define void @test_dynamic_stackalloc(i32 addrspace(1)* %out, i32 %n) {
   %alloca = alloca i32, i32 %n
   store volatile i32 0, i32* %alloca
   ret void
 }

test/CodeGen/AMDGPU/private-memory-broken.ll

-; RUN: not llc -verify-machineinstrs -march=amdgcn -mcpu=SI -exit-on-error %s -o /dev/null 2>&1 | FileCheck %s
-; RUN: not llc -verify-machineinstrs -march=amdgcn -mcpu=tonga -exit-on-error %s -o /dev/null 2>&1 | FileCheck %s
+; RUN: not llc -verify-machineinstrs -march=amdgcn -mcpu=SI %s -o /dev/null 2>&1 | FileCheck %s
+; RUN: not llc -verify-machineinstrs -march=amdgcn -mcpu=tonga %s -o /dev/null 2>&1 | FileCheck %s
 
 ; Make sure promote alloca pass doesn't crash
 
 ; CHECK: unsupported call
 
 declare i32 @foo(i32*) nounwind
 
 define void @call_private(i32 addrspace(1)* %out, i32 %in) nounwind {

test/CodeGen/AMDGPU/promote-alloca-bitcast-function.ll

-; RUN: not llc -march=amdgcn -exit-on-error < %s 2>&1 | FileCheck %s
+; RUN: not llc -march=amdgcn < %s 2>&1 | FileCheck %s
 
 ; Make sure that AMDGPUPromoteAlloca doesn't crash if the called
 ; function is a constantexpr cast of a function.
 
 declare void @foo(float*) #0
 declare void @foo.varargs(...) #0
 
 ; CHECK: in function crash_call_constexpr_cast{{.*}}: unsupported call to function foo
 define void @crash_call_constexpr_cast() #0 {
   %alloca = alloca i32
   call void bitcast (void (float*)* @foo to void (i32*)*)(i32* %alloca) #0
   ret void
 }
 
 define void @crash_call_constexpr_cast_varargs() #0 {
   %alloca = alloca i32
   call void bitcast (void (...)* @foo.varargs to void (i32*)*)(i32* %alloca) #0
   ret void
 }
 
 attributes #0 = { nounwind }