AMDGPU: Fix crashes on unknown processor name

If the processor name failed to parse for amdgcn,
the resulting output would have R600 ISA in it.

If the processor name was missing or invalid for R600,
the wavefront size would not be set and there would be
crashes from missing itinerary data.

Fixes crashes in future commit caused by dividing by the unset/0
wavefront size.

llvm-svn: 271561

1 files changed, 20 insertions, 0 deletions

diff --git a/llvm/test/CodeGen/AMDGPU/unknown-processor.ll b/llvm/test/CodeGen/AMDGPU/unknown-processor.ll
new file mode 100644
index 00000000000..941f4c601e3
--- /dev/null
+++ b/llvm/test/CodeGen/AMDGPU/unknown-processor.ll
@@ -0,0 +1,20 @@
+; RUN: llc -march=amdgcn -mcpu=unknown < %s 2>&1 | FileCheck -check-prefix=ERROR -check-prefix=GCN %s
+; RUN: llc -march=r600 -mcpu=unknown < %s 2>&1 | FileCheck -check-prefix=ERROR -check-prefix=R600 %s
+
+; Should not crash when the processor is not recognized and the
+; wavefront size feature not set.
+
+; Should also not have fragments of r600 and gcn isa mixed.
+
+; ERROR: 'unknown' is not a recognized processor for this target (ignoring processor)
+
+; GCN-NOT: MOV
+; GCN: buffer_store_dword
+; GCN: ScratchSize: 8{{$}}
+
+; R600: MOV
+define void @foo() {
+  %alloca = alloca i32, align 4
+  store volatile i32 0, i32* %alloca
+  ret void
+}