AMDGPU: Hack out noinline on functions using LDS globals
This is a workaround for clang adding noinline to all functions at
-O0. Previously, we would just add alwaysinline, and the verifier
would complain about having both noinline and alwaysinline. We
currently can't truly codegen this case as a freestanding function, so
override the user forcing noinline.
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp b/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp
index ff2bda6..2294754 100644
--- a/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp
+++ b/llvm/lib/Target/AMDGPU/AMDGPUAlwaysInlinePass.cpp
@@ -71,6 +71,13 @@
if (Instruction *I = dyn_cast<Instruction>(U)) {
Function *F = I->getParent()->getParent();
if (!AMDGPU::isEntryFunctionCC(F->getCallingConv())) {
+ // FIXME: This is a horrible hack. We should always respect noinline,
+ // and just let us hit the error when we can't handle this.
+ //
+ // Unfortunately, clang adds noinline to all functions at -O0. We have
+ // to override this here. until that's fixed.
+ F->removeFnAttr(Attribute::NoInline);
+
FuncsToAlwaysInline.insert(F);
Stack.push_back(F);
}
diff --git a/llvm/test/CodeGen/AMDGPU/force-alwaysinline-lds-global-address.ll b/llvm/test/CodeGen/AMDGPU/force-alwaysinline-lds-global-address.ll
index f525ca5..8ab59dc 100644
--- a/llvm/test/CodeGen/AMDGPU/force-alwaysinline-lds-global-address.ll
+++ b/llvm/test/CodeGen/AMDGPU/force-alwaysinline-lds-global-address.ll
@@ -74,4 +74,21 @@
ret i32 %call
}
+; Test we don't break the IR and have both alwaysinline and noinline
+; FIXME: We should really not override noinline.
+
+; ALL-LABEL: define i32 @load_lds_simple_noinline() #0 {
+define i32 @load_lds_simple_noinline() noinline {
+ %load = load i32, i32 addrspace(3)* @lds0, align 4
+ ret i32 %load
+}
+
+; ALL-LABEL: define i32 @recursive_call_lds_noinline(i32 %arg0) #0 {
+define i32 @recursive_call_lds_noinline(i32 %arg0) noinline {
+ %load = load i32, i32 addrspace(3)* @lds0, align 4
+ %add = add i32 %arg0, %load
+ %call = call i32 @recursive_call_lds(i32 %add)
+ ret i32 %call
+}
+
; ALL: attributes #0 = { alwaysinline }
