[llvm] [AMDGPU] Create local KnownBits in case DenseMap gets invalidated (PR #111568)

[Matt Arsenault via llvm-commits]

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@@ -1,120 +1,144 @@
-; REQUIRES: asserts
-; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1030 -o - %s 2>&1 | FileCheck %s
+; RUN: llc -mtriple=amdgcn-amd-amdhsa -mcpu=gfx1030 < %s | FileCheck %s
 
-; CHECK-NOT: Assertion `BitWidth == RHS.BitWidth && "Bit widths must be same for comparison"' failed
+; Previously, this would hit an assertion on incompatible comparison between
+; APInts due to BitWidth differences. This was due to assignment of DenseMap
+; value using another value within that same DenseMap which results in a
+; use-after-free if the assignment operator invokes a DenseMap growth.
 
-define void @RunTic() {
-  %call5.i1 = call i32 @G_CheckDemoStatus()
-  tail call void @D_AdvanceDemo()
-  call void @G_Ticker()
+; CHECK-LABEL: I_Quit:
+define void @I_Quit() {
+  %fptr = load ptr, ptr null, align 8
+  tail call void %fptr()
   ret void
 }
 
-define void @G_Ticker() {
-  call void @G_DoReborn()
-  tail call void @F_Ticker()
-  tail call void @AM_Stop()
-  tail call void @F_StartFinale()
-  tail call void @D_AdvanceDemo()
-  %call.i.i449 = call i32 @R_FlatNumForName()
-  %call9.i.i = call i32 @R_TextureNumForName()
-  %call.i306 = tail call ptr @P_TempSaveGameFile()
-  %call1.i307 = call ptr @P_SaveGameFile()
-  call void (...) @I_Error()
+; CHECK-LABEL: P_RemoveMobj:
+define void @P_RemoveMobj() {
   ret void
 }
 
-define void @G_DoReborn() {
-  call void @P_RemoveMobj()
-  call void @P_SpawnMobj()
-  call void @P_SpawnPlayer()
-  call void (...) @I_Error()
+; CHECK-LABEL: P_SpawnMobj:
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arsenm wrote:

Just checking all the labels isn't really useful

https://github.com/llvm/llvm-project/pull/111568