Author: dsanders Date: Wed Jan 14 06:00:12 2015 New Revision: 225981 URL: http://llvm.org/viewvc/llvm-project?rev=225981&view=rev Log: [mips] Handle transparent unions correctly.
Summary: This fixes MultiSource/Applications/lemon on big-endian N32 by correcting the handling of the argument to wait(). glibc defines it as a transparent union of void* and int*. Such unions are passed according to the rules of the first member so the argument must be passed as if it were a void* (sign extended from i32 to i64) and not as a union (shifted to the upper bits of an i64). wait() already behaves correctly on big-endian O32 and N64 since the union is already the same size as an argument slot. Reviewers: atanasyan Reviewed By: atanasyan Subscribers: cfe-commits Differential Revision: http://reviews.llvm.org/D6963 Added: cfe/trunk/test/CodeGen/mips-transparent-union.c Modified: cfe/trunk/lib/CodeGen/TargetInfo.cpp Modified: cfe/trunk/lib/CodeGen/TargetInfo.cpp URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/TargetInfo.cpp?rev=225981&r1=225980&r2=225981&view=diff ============================================================================== --- cfe/trunk/lib/CodeGen/TargetInfo.cpp (original) +++ cfe/trunk/lib/CodeGen/TargetInfo.cpp Wed Jan 14 06:00:12 2015 @@ -5693,6 +5693,8 @@ llvm::Type *MipsABIInfo::getPaddingType( ABIArgInfo MipsABIInfo::classifyArgumentType(QualType Ty, uint64_t &Offset) const { + Ty = useFirstFieldIfTransparentUnion(Ty); + uint64_t OrigOffset = Offset; uint64_t TySize = getContext().getTypeSize(Ty); uint64_t Align = getContext().getTypeAlign(Ty) / 8; Added: cfe/trunk/test/CodeGen/mips-transparent-union.c URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/CodeGen/mips-transparent-union.c?rev=225981&view=auto ============================================================================== --- cfe/trunk/test/CodeGen/mips-transparent-union.c (added) +++ cfe/trunk/test/CodeGen/mips-transparent-union.c Wed Jan 14 06:00:12 2015 @@ -0,0 +1,27 @@ +// RUN: %clang_cc1 -triple mips64-linux-gnu -S -o - -emit-llvm %s | FileCheck %s +// +// Transparent unions are passed according to the calling convention rules of +// the first member. In this case, it is as if it were a void pointer so we +// do not have the inreg attribute we would normally have for unions. +// +// This comes up in glibc's wait() function and matters for the big-endian N32 +// case where pointers are promoted to i64 and a non-transparent union would be +// passed in the upper 32-bits of an i64. + +union either_pointer { + void *void_ptr; + int *int_ptr; +} __attribute__((transparent_union)); + +extern void foo(union either_pointer p); + +int data; + +void bar(void) { + return foo(&data); +} + +// CHECK-LABEL: define void @bar() +// CHECK: call void @foo(i8* %{{[0-9]+}}) + +// CHECK: declare void @foo(i8*) _______________________________________________ cfe-commits mailing list [email protected] http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
