If the alignment of the byval argument is greater than the alignment

of the frame then increase the maximum alignment of the frame to
match.

Fixes PR6965


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@132764 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 61 insertions, 0 deletions

diff --git a/lib/CodeGen/CallingConvLower.cpp b/lib/CodeGen/CallingConvLower.cpp
index dac2fef5b4..bc61ec8ed0 100644
--- a/lib/CodeGen/CallingConvLower.cpp
+++ b/lib/CodeGen/CallingConvLower.cpp
@@ -49,6 +49,8 @@ void CCState::HandleByVal(unsigned ValNo, MVT ValVT,
     Size = MinSize;
   if (MinAlign > (int)Align)
     Align = MinAlign;
+  if (MF.getFrameInfo()->getMaxAlignment() < Align)
+    MF.getFrameInfo()->setMaxAlignment(Align);
   TM.getTargetLowering()->HandleByVal(const_cast<CCState*>(this), Size);
   unsigned Offset = AllocateStack(Size, Align);
   addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
diff --git a/test/CodeGen/X86/byval-align.ll b/test/CodeGen/X86/byval-align.ll
new file mode 100644
index 0000000000..c62a1814ba
--- /dev/null
+++ b/test/CodeGen/X86/byval-align.ll
@@ -0,0 +1,59 @@
+; RUN: llc < %s -mtriple=x86_64-linux | FileCheck %s
+%struct.S = type { i32}
+
+@.str = private constant [10 x i8] c"ptr = %p\0A\00", align 1 ; <[10 x i8]*> [#uses=1]
+@.str1 = private constant [8 x i8] c"Failed \00", align 1 ; <[8 x i8]*> [#uses=1]
+@.str2 = private constant [2 x i8] c"0\00", align 1 ; <[2 x i8]*> [#uses=1]
+@.str3 = private constant [7 x i8] c"test.c\00", align 1 ; <[7 x i8]*> [#uses=1]
+@__PRETTY_FUNCTION__.2067 = internal constant [13 x i8] c"aligned_func\00" ; <[13 x i8]*> [#uses=1]
+
+define void @aligned_func(%struct.S* byval align 64 %obj) nounwind {
+entry:
+  %ptr = alloca i8*                               ; <i8**> [#uses=3]
+  %p = alloca i64                                 ; <i64*> [#uses=3]
+  %"alloca point" = bitcast i32 0 to i32          ; <i32> [#uses=0]
+  %obj1 = bitcast %struct.S* %obj to i8*          ; <i8*> [#uses=1]
+  store i8* %obj1, i8** %ptr, align 8
+  %0 = load i8** %ptr, align 8                    ; <i8*> [#uses=1]
+  %1 = ptrtoint i8* %0 to i64                     ; <i64> [#uses=1]
+  store i64 %1, i64* %p, align 8
+  %2 = load i8** %ptr, align 8                    ; <i8*> [#uses=1]
+  %3 = call i32 (i8*, ...)* @printf(i8* getelementptr inbounds ([10 x i8]* @.str, i64 0, i64 0), i8* %2) nounwind ; <i32> [#uses=0]
+  %4 = load i64* %p, align 8                      ; <i64> [#uses=1]
+  %5 = and i64 %4, 140737488355264                ; <i64> [#uses=1]
+  %6 = load i64* %p, align 8                      ; <i64> [#uses=1]
+  %7 = icmp ne i64 %5, %6                         ; <i1> [#uses=1]
+  br i1 %7, label %bb, label %bb2
+
+bb:                                               ; preds = %entry
+  %8 = call i32 @puts(i8* getelementptr inbounds ([8 x i8]* @.str1, i64 0, i64 0)) nounwind ; <i32> [#uses=0]
+  call void @__assert_fail(i8* getelementptr inbounds ([2 x i8]* @.str2, i64 0, i64 0), i8* getelementptr inbounds ([7 x i8]* @.str3, i64 0, i64 0), i32 18, i8* getelementptr inbounds ([13 x i8]* @__PRETTY_FUNCTION__.2067, i64 0, i64 0)) noreturn nounwind
+  unreachable
+
+bb2:                                              ; preds = %entry
+  br label %return
+
+return:                                           ; preds = %bb2
+  ret void
+}
+
+declare i32 @printf(i8*, ...) nounwind
+
+declare i32 @puts(i8*)
+
+declare void @__assert_fail(i8*, i8*, i32, i8*) noreturn nounwind
+
+define void @main() nounwind {
+entry:
+; CHECK: main
+; CHECK: andq    $-64, %rsp
+  %s1 = alloca %struct.S                          ; <%struct.S*> [#uses=4]
+  %"alloca point" = bitcast i32 0 to i32          ; <i32> [#uses=0]
+  %0 = getelementptr inbounds %struct.S* %s1, i32 0, i32 0 ; <i32*> [#uses=1]
+  store i32 1, i32* %0, align 4
+  call void @aligned_func(%struct.S* byval align 64 %s1) nounwind
+  br label %return
+
+return:                                           ; preds = %entry
+  ret void
+}