[llvm] [InferAddressSpaces] Fix bad `addrspacecast` insertion for phinode (PR #163528)

[Kerang Mao via llvm-commits]

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@@ -0,0 +1,57 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
+; RUN: opt -S -passes='require<domtree>,infer-address-spaces' %s | FileCheck %s
+
+;;; Handle write corner case for infer-address-spaces with phi-nodes. The
+;;; verifier will crash if we insert `addrspacecast` before phi-node.
+
+target triple = "nvptx64-nvidia-cuda"
+
+declare void @llvm.assume(i1 noundef)
+declare i1 @llvm.nvvm.isspacep.shared(ptr) readnone noinline
+declare i1 @llvm.nvvm.isspacep.global(ptr) readnone noinline
+
+define ptr @phinode_instr() {
+; CHECK-LABEL: @phinode_instr(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[PTR_1:%.*]] = load ptr, ptr null, align 8
+; CHECK-NEXT:    [[TMP0:%.*]] = addrspacecast ptr [[PTR_1]] to ptr addrspace(3)
+; CHECK-NEXT:    [[BOOL_1:%.*]] = tail call i1 @llvm.nvvm.isspacep.shared(ptr [[PTR_1]])
+; CHECK-NEXT:    tail call void @llvm.assume(i1 [[BOOL_1]])
+; CHECK-NEXT:    br label [[IF_SINK_SPLIT:%.*]]
+; CHECK:       if.sink.split:
+; CHECK-NEXT:    [[PTR_SINK:%.*]] = phi ptr addrspace(3) [ [[TMP0]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[TMP1:%.*]] = addrspacecast ptr addrspace(3) [[PTR_SINK]] to ptr
+; CHECK-NEXT:    ret ptr [[TMP1]]
+;
+entry:
+  %ptr.1 = load ptr, ptr null, align 8
+  %bool.1 = tail call i1 @llvm.nvvm.isspacep.shared(ptr %ptr.1)
+  tail call void @llvm.assume(i1 %bool.1)
+  br label %if.sink.split
+
+if.sink.split:                                    ; preds = %entry
+  %ptr.sink = phi ptr [ %ptr.1, %entry ]
+  ret ptr %ptr.sink
+}
+
+define ptr @phinode_argument(ptr %lhs_ptr) {
+; CHECK-LABEL: @phinode_argument(
+; CHECK-NEXT:  entry:
+; CHECK-NEXT:    [[TMP0:%.*]] = addrspacecast ptr [[LHS_PTR:%.*]] to ptr addrspace(1)
+; CHECK-NEXT:    [[BOOL_1:%.*]] = tail call i1 @llvm.nvvm.isspacep.global(ptr [[LHS_PTR]])
+; CHECK-NEXT:    tail call void @llvm.assume(i1 [[BOOL_1]])
+; CHECK-NEXT:    br label [[IF_SINK_SPLIT:%.*]]
+; CHECK:       if.sink.split:
+; CHECK-NEXT:    [[PTR_SINK:%.*]] = phi ptr addrspace(1) [ [[TMP0]], [[ENTRY:%.*]] ]
+; CHECK-NEXT:    [[TMP1:%.*]] = addrspacecast ptr addrspace(1) [[PTR_SINK]] to ptr
+; CHECK-NEXT:    ret ptr [[TMP1]]
+;
+entry:
+  %bool.1 = tail call i1 @llvm.nvvm.isspacep.global(ptr %lhs_ptr)
+  tail call void @llvm.assume(i1 %bool.1)
+  br label %if.sink.split
+
+if.sink.split:                                    ; preds = %entry
+  %ptr.sink = phi ptr [ %lhs_ptr, %entry ]
+  ret ptr %ptr.sink
----------------
Kerang-BR wrote:

Revised and add a new lit case for AMDGPU.

https://github.com/llvm/llvm-project/pull/163528