simplifycfg: Preserve debuginfos when merging bbs

6 files changed, 287 insertions, 0 deletions

diff --git a/tests/mir-opt/debuginfo/simplifycfg.drop_debuginfo.SimplifyCfg-final.diff b/tests/mir-opt/debuginfo/simplifycfg.drop_debuginfo.SimplifyCfg-final.diff
index d4a73351ee4..7a1ac92f6dd 100644
--- a/tests/mir-opt/debuginfo/simplifycfg.drop_debuginfo.SimplifyCfg-final.diff
+++ b/tests/mir-opt/debuginfo/simplifycfg.drop_debuginfo.SimplifyCfg-final.diff
@@ -14,11 +14,13 @@
 - 
 -     bb1: {
 -         // DBG: _3 = &((*_1).0: i32);
+-         nop;
 -         goto -> bb2;
 -     }
 - 
 -     bb2: {
           // DBG: _4 = &((*_1).1: i64);
+-         nop;
           _0 = copy ((*_1).2: i32);
           return;
       }
diff --git a/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_1.SimplifyCfg-final.diff b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_1.SimplifyCfg-final.diff
index 1c12358ad89..fa4d3aebf83 100644
--- a/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_1.SimplifyCfg-final.diff
+++ b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_1.SimplifyCfg-final.diff
@@ -17,13 +17,16 @@
 -     bb1: {
           (*_2) = const true;
           // DBG: _3 = &((*_1).0: i32);
+-         nop;
 -         goto -> bb2;
 -     }
 - 
 -     bb2: {
           // DBG: _4 = &((*_1).1: i64);
+-         nop;
           _0 = copy ((*_1).2: i32);
           // DBG: _5 = &((*_1).2: i32);
+-         nop;
           return;
       }
   }
diff --git a/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_2.SimplifyCfg-final.diff b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_2.SimplifyCfg-final.diff
index de8e5612c87..b01c91f196b 100644
--- a/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_2.SimplifyCfg-final.diff
+++ b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_2.SimplifyCfg-final.diff
@@ -16,13 +16,16 @@
 - 
 -     bb1: {
           // DBG: _2 = &((*_1).0: i32);
+-         nop;
 -         goto -> bb2;
 -     }
 - 
 -     bb2: {
           // DBG: _3 = &((*_1).1: i64);
+-         nop;
           _0 = copy ((*_1).2: i32);
           // DBG: _4 = &((*_1).2: i32);
+-         nop;
           return;
       }
   }
diff --git a/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_3.SimplifyCfg-final.diff b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_3.SimplifyCfg-final.diff
new file mode 100644
index 00000000000..caa90d79a1c
--- /dev/null
+++ b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_3.SimplifyCfg-final.diff
@@ -0,0 +1,40 @@
+- // MIR for `preserve_debuginfo_3` before SimplifyCfg-final
++ // MIR for `preserve_debuginfo_3` after SimplifyCfg-final
+  
+  fn preserve_debuginfo_3(_1: &Foo, _2: bool) -> i32 {
+      debug foo_a => _3;
+      debug foo_b => _4;
+      debug foo_c => _5;
+      let mut _0: i32;
+      let mut _3: &i32;
+      let mut _4: &i64;
+      let mut _5: &i32;
+  
+      bb0: {
+-         switchInt(copy _2) -> [1: bb1, otherwise: bb2];
++         switchInt(copy _2) -> [1: bb2, otherwise: bb1];
+      }
+  
+      bb1: {
+-         // DBG: _3 = &((*_1).0: i32);
+-         nop;
+-         goto -> bb3;
+-     }
+- 
+-     bb2: {
+          // DBG: _4 = &((*_1).1: i64);
+-         nop;
+          _0 = copy ((*_1).2: i32);
+          return;
+      }
+  
+-     bb3: {
++     bb2: {
++         // DBG: _3 = &((*_1).0: i32);
+          // DBG: _5 = &((*_1).2: i32);
+-         nop;
+          _0 = copy ((*_1).0: i32);
+          return;
+      }
+  }
+  
diff --git a/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_identical_succs.SimplifyCfg-final.diff b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_identical_succs.SimplifyCfg-final.diff
new file mode 100644
index 00000000000..d8c36990a5f
--- /dev/null
+++ b/tests/mir-opt/debuginfo/simplifycfg.preserve_debuginfo_identical_succs.SimplifyCfg-final.diff
@@ -0,0 +1,32 @@
+- // MIR for `preserve_debuginfo_identical_succs` before SimplifyCfg-final
++ // MIR for `preserve_debuginfo_identical_succs` after SimplifyCfg-final
+  
+  fn preserve_debuginfo_identical_succs(_1: &Foo, _2: bool) -> i32 {
+      debug foo_a => _3;
+      debug foo_b => _4;
+      debug foo_c => _5;
+      let mut _0: i32;
+      let mut _3: &i32;
+      let mut _4: &i64;
+      let mut _5: &i32;
+  
+      bb0: {
+-         switchInt(copy _2) -> [1: bb1, otherwise: bb1];
+-     }
+- 
+-     bb1: {
+          // DBG: _3 = &((*_1).0: i32);
+-         nop;
+-         goto -> bb2;
+-     }
+- 
+-     bb2: {
+          // DBG: _4 = &((*_1).1: i64);
+-         nop;
+          _0 = copy ((*_1).2: i32);
+          // DBG: _5 = &((*_1).2: i32);
+-         nop;
+          return;
+      }
+  }
+  
diff --git a/tests/mir-opt/debuginfo/simplifycfg.rs b/tests/mir-opt/debuginfo/simplifycfg.rs
new file mode 100644
index 00000000000..2bd510fd3b9
--- /dev/null
+++ b/tests/mir-opt/debuginfo/simplifycfg.rs
@@ -0,0 +1,207 @@
+//@ test-mir-pass: SimplifyCfg-final
+//@ compile-flags: -Zmir-enable-passes=+DeadStoreElimination-initial
+
+#![feature(core_intrinsics, custom_mir)]
+#![crate_type = "lib"]
+
+use std::intrinsics::mir::*;
+
+pub struct Foo {
+    a: i32,
+    b: i64,
+    c: i32,
+}
+
+// EMIT_MIR simplifycfg.drop_debuginfo.SimplifyCfg-final.diff
+#[custom_mir(dialect = "runtime", phase = "post-cleanup")]
+pub fn drop_debuginfo(foo: &Foo, c: bool) -> i32 {
+    // CHECK-LABEL: fn drop_debuginfo
+    // CHECK: debug foo_b => [[foo_b:_[0-9]+]];
+    // CHECK: bb0: {
+    // CHECK-NEXT: DBG: [[foo_b]] = &((*_1).1: i64)
+    // CHECK-NEXT: _0 = copy ((*_1).2: i32);
+    // CHECK-NEXT: return;
+    mir! {
+        let _foo_a: &i32;
+        let _foo_b: &i64;
+        debug foo_a => _foo_a;
+        debug foo_b => _foo_b;
+        {
+            match c {
+                true => tmp,
+                _ => ret,
+            }
+        }
+        tmp = {
+            // Because we don't know if `c` is always true, we must drop this debuginfo.
+            _foo_a = &(*foo).a;
+            Goto(ret)
+        }
+        ret = {
+            _foo_b = &(*foo).b;
+            RET = (*foo).c;
+            Return()
+        }
+    }
+}
+
+// EMIT_MIR simplifycfg.preserve_debuginfo_1.SimplifyCfg-final.diff
+#[custom_mir(dialect = "runtime", phase = "post-cleanup")]
+pub fn preserve_debuginfo_1(foo: &Foo, v: &mut bool) -> i32 {
+    // CHECK-LABEL: fn preserve_debuginfo_1
+    // CHECK: debug foo_a => [[foo_a:_[0-9]+]];
+    // CHECK: debug foo_b => [[foo_b:_[0-9]+]];
+    // CHECK: debug foo_c => [[foo_c:_[0-9]+]];
+    // CHECK: bb0: {
+    // CHECK-NEXT: (*_2) = const true;
+    // CHECK-NEXT: DBG: [[foo_a]] = &((*_1).0: i32)
+    // CHECK-NEXT: DBG: [[foo_b]] = &((*_1).1: i64)
+    // CHECK-NEXT: _0 = copy ((*_1).2: i32);
+    // CHECK-NEXT: DBG: [[foo_c]] = &((*_1).2: i32)
+    // CHECK-NEXT: return;
+    mir! {
+        let _foo_a: &i32;
+        let _foo_b: &i64;
+        let _foo_c: &i32;
+        debug foo_a => _foo_a;
+        debug foo_b => _foo_b;
+        debug foo_c => _foo_c;
+        {
+            Goto(tmp)
+        }
+        tmp = {
+            *v = true;
+            _foo_a = &(*foo).a;
+            Goto(ret)
+        }
+        ret = {
+            _foo_b = &(*foo).b;
+            RET = (*foo).c;
+            _foo_c = &(*foo).c;
+            Return()
+        }
+    }
+}
+
+// EMIT_MIR simplifycfg.preserve_debuginfo_2.SimplifyCfg-final.diff
+#[custom_mir(dialect = "runtime", phase = "post-cleanup")]
+pub fn preserve_debuginfo_2(foo: &Foo) -> i32 {
+    // CHECK-LABEL: fn preserve_debuginfo_2
+    // CHECK: debug foo_a => [[foo_a:_[0-9]+]];
+    // CHECK: debug foo_b => [[foo_b:_[0-9]+]];
+    // CHECK: debug foo_c => [[foo_c:_[0-9]+]];
+    // CHECK: bb0: {
+    // CHECK-NEXT: DBG: [[foo_a]] = &((*_1).0: i32)
+    // CHECK-NEXT: DBG: [[foo_b]] = &((*_1).1: i64)
+    // CHECK-NEXT: _0 = copy ((*_1).2: i32);
+    // CHECK-NEXT: DBG: [[foo_c]] = &((*_1).2: i32)
+    // CHECK-NEXT: return;
+    mir! {
+        let _foo_a: &i32;
+        let _foo_b: &i64;
+        let _foo_c: &i32;
+        debug foo_a => _foo_a;
+        debug foo_b => _foo_b;
+        debug foo_c => _foo_c;
+        {
+            Goto(tmp)
+        }
+        tmp = {
+            _foo_a = &(*foo).a;
+            Goto(ret)
+        }
+        ret = {
+            _foo_b = &(*foo).b;
+            RET = (*foo).c;
+            _foo_c = &(*foo).c;
+            Return()
+        }
+    }
+}
+
+// EMIT_MIR simplifycfg.preserve_debuginfo_3.SimplifyCfg-final.diff
+#[custom_mir(dialect = "runtime", phase = "post-cleanup")]
+pub fn preserve_debuginfo_3(foo: &Foo, c: bool) -> i32 {
+    // CHECK-LABEL: fn preserve_debuginfo_3
+    // CHECK: debug foo_a => [[foo_a:_[0-9]+]];
+    // CHECK: debug foo_b => [[foo_b:_[0-9]+]];
+    // CHECK: debug foo_c => [[foo_c:_[0-9]+]];
+    // CHECK: bb0: {
+    // CHECK-NEXT: switchInt(copy _2) -> [1: bb2, otherwise: bb1];
+    // CHECK: bb1: {
+    // CHECK-NEXT: DBG: [[foo_b]] = &((*_1).1: i64)
+    // CHECK-NEXT: _0 = copy ((*_1).2: i32);
+    // CHECK-NEXT: return;
+    // CHECK: bb2: {
+    // CHECK-NEXT: DBG: [[foo_a]] = &((*_1).0: i32)
+    // CHECK-NEXT: DBG: [[foo_c]] = &((*_1).2: i32)
+    // CHECK-NEXT: _0 = copy ((*_1).0: i32);
+    // CHECK-NEXT: return;
+    mir! {
+        let _foo_a: &i32;
+        let _foo_b: &i64;
+        let _foo_c: &i32;
+        debug foo_a => _foo_a;
+        debug foo_b => _foo_b;
+        debug foo_c => _foo_c;
+        {
+            match c {
+                true => tmp,
+                _ => ret,
+            }
+        }
+        tmp = {
+            _foo_a = &(*foo).a;
+            Goto(ret_1)
+        }
+        ret = {
+            _foo_b = &(*foo).b;
+            RET = (*foo).c;
+            Return()
+        }
+        ret_1 = {
+            _foo_c = &(*foo).c;
+            RET = (*foo).a;
+            Return()
+        }
+    }
+}
+
+// EMIT_MIR simplifycfg.preserve_debuginfo_identical_succs.SimplifyCfg-final.diff
+#[custom_mir(dialect = "runtime", phase = "post-cleanup")]
+pub fn preserve_debuginfo_identical_succs(foo: &Foo, c: bool) -> i32 {
+    // CHECK-LABEL: fn preserve_debuginfo_identical_succs
+    // CHECK: debug foo_a => [[foo_a:_[0-9]+]];
+    // CHECK: debug foo_b => [[foo_b:_[0-9]+]];
+    // CHECK: debug foo_c => [[foo_c:_[0-9]+]];
+    // CHECK: bb0: {
+    // CHECK-NEXT: DBG: [[foo_a]] = &((*_1).0: i32)
+    // CHECK-NEXT: DBG: [[foo_b]] = &((*_1).1: i64)
+    // CHECK-NEXT: _0 = copy ((*_1).2: i32);
+    // CHECK-NEXT: DBG: [[foo_c]] = &((*_1).2: i32)
+    // CHECK-NEXT: return;
+    mir! {
+        let _foo_a: &i32;
+        let _foo_b: &i64;
+        let _foo_c: &i32;
+        debug foo_a => _foo_a;
+        debug foo_b => _foo_b;
+        debug foo_c => _foo_c;
+        {
+            match c {
+                true => tmp,
+                _ => tmp,
+            }
+        }
+        tmp = {
+            _foo_a = &(*foo).a;
+            Goto(ret)
+        }
+        ret = {
+            _foo_b = &(*foo).b;
+            RET = (*foo).c;
+            _foo_c = &(*foo).c;
+            Return()
+        }
+    }
+}