AMDGPU/SI: Add debugging subtarget feature for DS offsets

[oota-llvm.git] / lib / Target / AMDGPU / AMDGPU.td

diff --git a/lib/Target/AMDGPU/AMDGPU.td b/lib/Target/AMDGPU/AMDGPU.td
index 569ad3844b2533193ad5a24c485785a9946f56e3..ef8ef6268548e2add91636a65685753bc94c67dc 100644 (file)
--- a/lib/Target/AMDGPU/AMDGPU.td
+++ b/lib/Target/AMDGPU/AMDGPU.td
@@ -98,6 +98,16 @@ def FeatureEnableLoadStoreOpt : SubtargetFeature <"load-store-opt",
         "true",
         "Enable SI load/store optimizer pass">;
 
+// Performance debugging feature. Allow using DS instruction immediate
+// offsets even if the base pointer can't be proven to be base. On SI,
+// base pointer values that won't give the same result as a 16-bit add
+// are not safe to fold, but this will override the conservative test
+// for the base pointer.
+def FeatureEnableUnsafeDSOffsetFolding : SubtargetFeature <"unsafe-ds-offset-folding",
+        "EnableUnsafeDSOffsetFolding",
+        "true",
+        "Force using DS instruction immediate offsets on SI">;
+
 def FeatureFlatAddressSpace : SubtargetFeature<"flat-address-space",
         "FlatAddressSpace",
         "true",