[llvm] [WebAssembly] Handle block and polymorphic stack in AsmTypeCheck (PR #110770)

[Derek Schuff via llvm-commits]

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@@ -0,0 +1,182 @@
+# RUN: llvm-mc -triple=wasm32-unknown-unknown -mattr=+exception-handling < %s | FileCheck %s
+# Check that it converts to .o without errors, but don't check any output:
+# RUN: llvm-mc -triple=wasm32-unknown-unknown -mattr=+exception-handling -filetype=obj -o %t.o < %s
+
+  .tagtype  __cpp_exception i32
+
+block_branch_test:
+  .functype  block_branch_test () -> ()
+
+  # Block input paramter / return tests
+
+  i32.const 0
+  block (i32) -> (i32)
+  end_block
+  drop
+
+  i32.const 0
+  i64.const 0
+  block (i32, i64) -> (i32, f32)
+    drop
+    f32.const 0.0
+  end_block
+  drop
+  drop
+
+  i32.const 0
+  loop (i32) -> (f32)
+    drop
+    f32.const 0.0
+  end_loop
+  drop
+
+  i32.const 0
+  i32.const 0
+  if (i32) -> (i32)
+  else
+    i32.popcnt
+  end_if
+  drop
+
+  try i32
+    i32.const 0
+  catch       __cpp_exception
+    i32.clz
+  catch_all
+    i32.const 5
+  end_try
+  drop
+
+  i32.const 0
+  block (i32) -> (i32)
+    block (i32) -> (f32)
+      drop
+      f32.const 0.0
+    end_block
+    drop
+    i32.const 0
+  end_block
+  drop
+
+  # Branch tests
+
+  block f32
+    f32.const 0.0
+    i32.const 0
+    br_if 0
+    f32.const 1.0
+    br 0
+    # After 'br', we can pop any values from the polymorphic stack
+    i32.add
+    i32.sub
+    i32.mul
+    drop
+  end_block
+  drop
+
+  block () -> (f32, f64)
+    f32.const 0.0
+    f64.const 0.0
+    i32.const 0
+    br_if 0
+    block (f32, f64) -> (f32, f64)
+      i32.const 1
+      br_if 0
+    end_block
+  end_block
+  drop
+  drop
+
+  # Withina loop, branches target the start of the loop
----------------
dschuff wrote:

```suggestion
  # Within a loop, branches target the start of the loop
```

https://github.com/llvm/llvm-project/pull/110770