8 files changed, 42 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/MIRParser/MIRParser.cpp b/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
index e505ab4baeb..e5ba0322235 100644
--- a/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
+++ b/llvm/lib/CodeGen/MIRParser/MIRParser.cpp
@@ -275,6 +275,9 @@ bool MIRParserImpl::initializeMachineFunction(MachineFunction &MF) {
                    Twine(YamlMBB.ID));
   }
 
+  if (YamlMF.BasicBlocks.empty())
+    return error(Twine("machine function '") + Twine(MF.getName()) +
+                 "' requires at least one machine basic block in its body");
   // Initialize the machine basic blocks after creating them all so that the
   // machine instructions parser can resolve the MBB references.
   unsigned I = 0;
diff --git a/llvm/test/CodeGen/MIR/llvmIR.mir b/llvm/test/CodeGen/MIR/llvmIR.mir
index 4d7fde240c5..3c084ad7d39 100644
--- a/llvm/test/CodeGen/MIR/llvmIR.mir
+++ b/llvm/test/CodeGen/MIR/llvmIR.mir
@@ -32,4 +32,6 @@
 ...
 ---
 name: foo
+body:
+  - id: 0
 ...
diff --git a/llvm/test/CodeGen/MIR/llvmIRMissing.mir b/llvm/test/CodeGen/MIR/llvmIRMissing.mir
index 83d846ba44c..80cea5a6fda 100644
--- a/llvm/test/CodeGen/MIR/llvmIRMissing.mir
+++ b/llvm/test/CodeGen/MIR/llvmIRMissing.mir
@@ -4,4 +4,6 @@
 ---
 # CHECK: name: foo
 name: foo
+body:
+  - id: 0
 ...
diff --git a/llvm/test/CodeGen/MIR/machine-function-missing-body-error.mir b/llvm/test/CodeGen/MIR/machine-function-missing-body-error.mir
new file mode 100644
index 00000000000..0dc7477f627
--- /dev/null
+++ b/llvm/test/CodeGen/MIR/machine-function-missing-body-error.mir
@@ -0,0 +1,15 @@
+# RUN: not llc -start-after branch-folder -stop-after branch-folder -o /dev/null %s 2>&1 | FileCheck %s
+# This test ensures that the MIR parser reports an error when it encounters a
+# machine function with an empty body.
+
+--- |
+
+  define i32 @foo() {
+    ret i32 0
+  }
+
+...
+---
+# CHECK: machine function 'foo' requires at least one machine basic block in its body
+name:            foo
+...
diff --git a/llvm/test/CodeGen/MIR/machine-function-missing-function.mir b/llvm/test/CodeGen/MIR/machine-function-missing-function.mir
index eed4142d659..424c34aae84 100644
--- a/llvm/test/CodeGen/MIR/machine-function-missing-function.mir
+++ b/llvm/test/CodeGen/MIR/machine-function-missing-function.mir
@@ -12,8 +12,12 @@
 ...
 ---
 name:            foo
+body:
+  - id: 0
 ...
 ---
 # CHECK: function 'faa' isn't defined in the provided LLVM IR
 name:            faa
+body:
+  - id: 0
 ...
diff --git a/llvm/test/CodeGen/MIR/machine-function-missing-name.mir b/llvm/test/CodeGen/MIR/machine-function-missing-name.mir
index b16156e54bd..a868a65d35f 100644
--- a/llvm/test/CodeGen/MIR/machine-function-missing-name.mir
+++ b/llvm/test/CodeGen/MIR/machine-function-missing-name.mir
@@ -16,7 +16,11 @@
 ---
 # CHECK: [[@LINE+1]]:1: missing required key 'name'
 nme:             foo
+body:
+  - id: 0
 ...
 ---
 name:            bar
+body:
+  - id: 0
 ...
diff --git a/llvm/test/CodeGen/MIR/machine-function.mir b/llvm/test/CodeGen/MIR/machine-function.mir
index 8f053adc22b..afd10ab02c2 100644
--- a/llvm/test/CodeGen/MIR/machine-function.mir
+++ b/llvm/test/CodeGen/MIR/machine-function.mir
@@ -27,6 +27,8 @@
 # CHECK-NEXT: hasInlineAsm: false
 # CHECK: ...
 name:            foo
+body:
+  - id: 0
 ...
 ---
 # CHECK: name: bar
@@ -35,6 +37,8 @@ name:            foo
 # CHECK-NEXT: hasInlineAsm: false
 # CHECK: ...
 name:            bar
+body:
+  - id: 0
 ...
 ---
 # CHECK: name: func
@@ -44,6 +48,8 @@ name:            bar
 # CHECK: ...
 name:            func
 alignment:       8
+body:
+  - id: 0
 ...
 ---
 # CHECK: name: func2
@@ -55,4 +61,6 @@ name:            func2
 alignment:       16
 exposesReturnsTwice: true
 hasInlineAsm:    true
+body:
+  - id: 0
 ...
diff --git a/llvm/test/CodeGen/MIR/register-info.mir b/llvm/test/CodeGen/MIR/register-info.mir
index c01997b4685..9585faa9622 100644
--- a/llvm/test/CodeGen/MIR/register-info.mir
+++ b/llvm/test/CodeGen/MIR/register-info.mir
@@ -22,6 +22,8 @@
 # CHECK-NEXT: tracksSubRegLiveness: false
 # CHECK: ...
 name:            foo
+body:
+  - id: 0
 ...
 ---
 # CHECK: name: bar
@@ -33,4 +35,6 @@ name: bar
 isSSA: false
 tracksRegLiveness: true
 tracksSubRegLiveness: true
+body:
+  - id: 0
 ...