[move-2024] Fix issue with namd block cfg lowering (MystenLabs#15791)

## Description 

This fixes a bug for named blocks.

## Test Plan 

New tests that work 
---
If your changes are not user-facing and do not break anything, you can
skip the following section. Otherwise, please briefly describe what has
changed under the Release Notes section.

### Type of Change (Check all that apply)

- [ ] protocol change
- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes

external-crates/move/crates/move-compiler-transactional-tests/tests/control_flow/unused_named_blocks.exp

@@ -0,0 +1 @@
+processed 3 tasks

external-crates/move/crates/move-compiler-transactional-tests/tests/control_flow/unused_named_blocks.move

@@ -0,0 +1,100 @@
+//# init --edition 2024.alpha
+
+//# publish
+module 0x42::m {
+
+    public fun t0(): u64 {
+        if ('block: { true }) {
+            10
+        } else {
+            20
+        }
+    }
+
+    public fun t1(): u64 {
+        if ('block: { true }) {
+            'block: { 10 }
+        } else {
+            20
+        }
+    }
+
+    public fun t2(): u64 {
+        if ('block: { false }) {
+            20
+        } else {
+            'block: { 10 }
+        }
+    }
+
+    public fun t3(): u64 {
+        if ('block: { false }) {
+            20
+        } else {
+            while (false) { 'block: { 20 }; };
+            'block: { 10 }
+        }
+    }
+
+    public fun t4(): u64 {
+        let mut count = 0;
+        let mut x = 0;
+        while (x < 10) {
+            'inner: {
+                count = count + 1;
+            };
+            x = x + 1;
+        };
+        count
+    }
+
+    public fun t5(): u64 {
+        let mut count = 0;
+        let (start, stop) = (0, 10);
+        let mut i = start;
+        while (i < stop) {
+            let x = i;
+            count = count + x * x;
+            i = i + 1;
+        };
+        count
+    }
+
+    public fun t6(): u64 {
+        let mut count = 0u64;
+            {
+            let (start, stop) = (0, 10);
+            'macro:  {
+                'lambdabreak:  {
+                        {
+                        let mut i = start;
+                        while (i < stop) 'loop: {
+                                {
+                                let x = i;
+                                'lambdareturn:  {
+                                    count = count + x * x;
+                                }
+                            };
+                            i = i + 1;
+                        }
+                    }
+                }
+            }
+        };
+        count
+    }
+}
+
+//# run
+module 0x42::main {
+use 0x42::m;
+fun main() {
+    assert!(m::t0() == 10, 0);
+    assert!(m::t1() == 10, 1);
+    assert!(m::t2() == 10, 2);
+    assert!(m::t3() == 10, 3);
+    assert!(m::t4() == 10, 4);
+    assert!(m::t5() == 285, 5);
+    assert!(m::t6() == 285, 6);
+}
+}

external-crates/move/crates/move-compiler/src/cfgir/translate.rs

@@ -831,7 +831,7 @@ fn statement(
 
             let (body_entry_block, body_blocks) = block_(
                 context,
-                with_last(body, make_jump(sloc, start_label, false)),
+                with_last(body, make_jump(sloc, end_label, false)),
             );
 
             context.exit_named_block(&name);

external-crates/move/crates/move-compiler/src/hlir/ast.rs

@@ -1130,12 +1130,13 @@ impl AstDebug for Statement_ {
                 if *has_break {
                     w.write("#has_break");
                 }
+                w.write(" ");
                 name.ast_debug(w);
                 w.write(": ");
                 w.block(|w| block.ast_debug(w))
             }
             S::NamedBlock { name, block } => {
-                w.write("loop");
+                w.write("named-block ");
                 name.ast_debug(w);
                 w.write(": ");
                 w.block(|w| block.ast_debug(w))

external-crates/move/crates/move-compiler/tests/move_2024/cfgir/loops.move

@@ -0,0 +1,38 @@
+
+module 0x42::m {
+    fun t0() {
+        let mut count = 0;
+        let (start, stop) = (0, 10);
+        let mut i = start;
+        while (i < stop) {
+            let x = i;
+            count = count + x * x;
+            i = i + 1;
+        };
+        assert!(count == 285, 0);
+    }
+
+    fun t1() {
+        let mut count = 0u64;
+            {
+            let (start, stop) = (0, 10);
+            'macro:  {
+                'lambdabreak:  {
+                        {
+                        let mut i = start;
+                        while (i < stop) 'loop: {
+                                {
+                                let x = i;
+                                'lambdareturn:  {
+                                    count = count + x * x;
+                                }
+                            };
+                            i = i + 1;
+                        }
+                    }
+                }
+            }
+        };
+        assert!(count == 285, 0);
+    }
+}

external-crates/move/crates/move-compiler/tests/move_2024/cfgir/named_blocks.move

@@ -0,0 +1,48 @@
+module 0x42::a {
+
+    fun t0(): u64 {
+        if ('block: { true }) {
+            10
+        } else {
+            20
+        }
+    }
+
+    fun t1(): u64 {
+        if ('block: { true }) {
+            'block: { 10 }
+        } else {
+            20
+        }
+    }
+
+    fun t2(): u64 {
+        if ('block: { false }) {
+            20
+        } else {
+            'block: { 10 }
+        }
+    }
+
+    fun t3(): u64 {
+        if ('block: { false }) {
+            20
+        } else {
+            while (false) { 'block: { 20 }; };
+            'block: { 10 }
+        }
+    }
+
+    fun t4(): u64 {
+        let mut count = 0;
+        let mut x = 0;
+        while (x < 10) {
+            'inner: {
+                count = count + 1;
+            };
+            x = x + 1;
+        };
+        count
+    }
+
+}