Darwin x86_32: Ignore arrays of empty structures inside records.

 - This eliminates 5/1000 failures on return-types-32, on the current
   ABITest config.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71250 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 13 insertions, 3 deletions

diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 27322525bb..e9f2bba303 100644
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -350,6 +350,13 @@ bool X86_32ABIInfo::shouldReturnTypeInRegister(QualType Ty,
     if (isEmptyRecord(Context, FD->getType()))
       continue;
 
+    // As are arrays of empty structures, but not generally, so we
+    // can't add this test higher in this routine.
+    if (const ConstantArrayType *AT = 
+        Context.getAsConstantArrayType(FD->getType()))
+      if (isEmptyRecord(Context, AT->getElementType()))
+        continue;
+
     // Check fields recursively.
     if (!shouldReturnTypeInRegister(FD->getType(), Context))
       return false;
diff --git a/test/CodeGen/x86_32-arguments.c b/test/CodeGen/x86_32-arguments.c
index 95307e929a..14144c438c 100644
--- a/test/CodeGen/x86_32-arguments.c
+++ b/test/CodeGen/x86_32-arguments.c
@@ -120,10 +120,13 @@ struct { struct {} a; struct { float a[1]; } b; } f25(void) {}
 // Small structures are handled recursively
 // RUN: grep -F 'i32 @f26()' %t &&
 // RUN: grep 'void @f27(%.truct.s27\* noalias sret %agg.result)' %t &&
-struct s26 { struct { char a, b; } a; struct { char a, b } b; } f26(void) {}
-struct s27 { struct { char a, b, c; } a; struct { char a } b; } f27(void) {}
+struct s26 { struct { char a, b; } a; struct { char a, b; } b; } f26(void) {}
+struct s27 { struct { char a, b, c; } a; struct { char a; } b; } f27(void) {}
 
 // RUN: grep 'void @f28(%.truct.s28\* noalias sret %agg.result)' %t &&
-struct s28 { int a; int b[] } f28(void) {}
+struct s28 { int a; int b[]; } f28(void) {}
+
+// RUN: grep 'define i16 @f29()' %t &&
+struct s29 { struct { } a[1]; char b; char c; } f29(void) {}
 
 // RUN: true