[AMDGPU] Fix DynLDS causing crash when LowerLDS is run at fullLTO pipeline

llvm/lib/Target/AMDGPU/Utils/AMDGPUMemoryUtils.cpp

@@ -207,14 +207,19 @@ LDSUsesInfoTy getTransitiveUsesOfLDS(const CallGraph &CG, Module &M) {
   }
 
   // Verify that we fall into one of 2 cases:
-  //    - All variables are absolute: this is a re-run of the pass
+  //    - All variables are either absolute 
+  //      or direct mapped dynamic LDS that is not lowered.
+  //      this is a re-run of the pass
   //      so we don't have anything to do.
   //    - No variables are absolute.
   std::optional<bool> HasAbsoluteGVs;
   for (auto &Map : {DirectMapKernel, IndirectMapKernel}) {
     for (auto &[Fn, GVs] : Map) {
       for (auto *GV : GVs) {
         bool IsAbsolute = GV->isAbsoluteSymbolRef();
+        bool IsDirectMapDynLDSGV = AMDGPU::isDynamicLDS(*GV) && DirectMapKernel.contains(Fn);
+        if (IsDirectMapDynLDSGV)
+          continue;
         if (HasAbsoluteGVs.has_value()) {
           if (*HasAbsoluteGVs != IsAbsolute) {
             report_fatal_error(

llvm/test/CodeGen/AMDGPU/lds-mixed-absolute-dynlds.ll

@@ -0,0 +1,25 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -S -mtriple=amdgcn-- -amdgpu-lower-module-lds < %s 2>&1 | FileCheck %s
+; RUN: opt -S -mtriple=amdgcn-- -passes=amdgpu-lower-module-lds < %s 2>&1 | FileCheck %s
+
+; Dynamic LDS that are direct mapped are not lowered in LowerModuleLDS pass.
+; In such cases, LowerModuleLDS is free to leave it in and ignore it, and we want to make sure
+; LowerModuleLDS doesn't crash if it re-runs on such modules.
+
+@loweredlds = addrspace(3) global i32 poison, !absolute_symbol !0
+@dynlds = external addrspace(3) global [0 x i32]
+
+define amdgpu_kernel void @kern(i32 %val0) {
+; CHECK-LABEL: define amdgpu_kernel void @kern(
+; CHECK-SAME: i32 [[VAL0:%.*]]) {
+; CHECK-NEXT:    store i32 0, ptr addrspace(3) @loweredlds, align 4
+; CHECK-NEXT:    store i32 1, ptr addrspace(3) @dynlds, align 4
+; CHECK-NEXT:    ret void
+;
+  store i32 0, ptr addrspace(3) @loweredlds
+  store i32 1, ptr addrspace(3) @dynlds
+  ret void
+}
+
+
+!0 = !{i32 0, i32 1}

llvm/test/CodeGen/AMDGPU/lds-run-twice.ll

@@ -7,10 +7,12 @@
 ; Check AMDGPULowerModuleLDS can run more than once on the same module, and that
 ; the second run is a no-op.
 
+@dynlds = external addrspace(3) global [0 x i32], align 4
 @lds = internal unnamed_addr addrspace(3) global i32 undef, align 4
 
 define amdgpu_kernel void @test() {
 entry:
+  store i32 0, ptr addrspace(3) @dynlds
   store i32 1, ptr addrspace(3) @lds
   ret void
 }