Add support for having different alignment for objects on call frames.

The x86-64 ABI states that objects passed on the stack have
8 byte alignment. Implement that.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41768 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Rafael Espindola 2007-09-07 14:52:14 +00:00
parent 8806c7b1f5
commit 588af2fb99
5 changed files with 57 additions and 9 deletions

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@ -38,7 +38,8 @@ enum AlignTypeEnum {
INTEGER_ALIGN = 'i', ///< Integer type alignment
VECTOR_ALIGN = 'v', ///< Vector type alignment
FLOAT_ALIGN = 'f', ///< Floating point type alignment
AGGREGATE_ALIGN = 'a' ///< Aggregate alignment
AGGREGATE_ALIGN = 'a', ///< Aggregate alignment
STACK_ALIGN = 's' ///< Stack objects alignment
};
/// Target alignment element.
///
@ -166,6 +167,11 @@ public:
/// specified type.
unsigned char getABITypeAlignment(const Type *Ty) const;
/// getCallFrameTypeAlignment - Return the minimum ABI-required alignment
/// for the specified type when it is part of a call frame.
unsigned char getCallFrameTypeAlignment(const Type *Ty) const;
/// getPrefTypeAlignment - Return the preferred stack/global alignment for
/// the specified type.
unsigned char getPrefTypeAlignment(const Type *Ty) const;

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@ -3870,7 +3870,8 @@ TargetLowering::LowerArguments(Function &F, SelectionDAG &DAG) {
Flags |= ISD::ParamFlags::ByVal;
const PointerType *Ty = cast<PointerType>(I->getType());
const StructType *STy = cast<StructType>(Ty->getElementType());
unsigned StructAlign = Log2_32(getTargetData()->getABITypeAlignment(STy));
unsigned StructAlign =
Log2_32(getTargetData()->getCallFrameTypeAlignment(STy));
unsigned StructSize = getTargetData()->getTypeSize(STy);
Flags |= (StructAlign << ISD::ParamFlags::ByValAlignOffs);
Flags |= (StructSize << ISD::ParamFlags::ByValSizeOffs);
@ -3999,7 +4000,8 @@ TargetLowering::LowerCallTo(SDOperand Chain, const Type *RetTy,
Flags |= ISD::ParamFlags::ByVal;
const PointerType *Ty = cast<PointerType>(Args[i].Ty);
const StructType *STy = cast<StructType>(Ty->getElementType());
unsigned StructAlign = Log2_32(getTargetData()->getABITypeAlignment(STy));
unsigned StructAlign =
Log2_32(getTargetData()->getCallFrameTypeAlignment(STy));
unsigned StructSize = getTargetData()->getTypeSize(STy);
Flags |= (StructAlign << ISD::ParamFlags::ByValAlignOffs);
Flags |= (StructSize << ISD::ParamFlags::ByValSizeOffs);

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@ -182,7 +182,8 @@ void TargetData::init(const std::string &TargetDescription) {
setAlignment(VECTOR_ALIGN, 8, 8, 64); // v2i32
setAlignment(VECTOR_ALIGN, 16, 16, 128); // v16i8, v8i16, v4i32, ...
setAlignment(AGGREGATE_ALIGN, 0, 8, 0); // struct, union, class, ...
setAlignment(STACK_ALIGN, 0, 8, 0); // objects on the stack
while (!temp.empty()) {
std::string token = getToken(temp, "-");
std::string arg0 = getToken(token, ":");
@ -204,10 +205,16 @@ void TargetData::init(const std::string &TargetDescription) {
case 'i':
case 'v':
case 'f':
case 'a': {
AlignTypeEnum align_type =
(*p == 'i' ? INTEGER_ALIGN : (*p == 'f' ? FLOAT_ALIGN :
(*p == 'v' ? VECTOR_ALIGN : AGGREGATE_ALIGN)));
case 'a':
case 's': {
AlignTypeEnum align_type;
switch(*p) {
case 'i': align_type = INTEGER_ALIGN; break;
case 'v': align_type = VECTOR_ALIGN; break;
case 'f': align_type = FLOAT_ALIGN; break;
case 'a': align_type = AGGREGATE_ALIGN; break;
case 's': align_type = STACK_ALIGN; break;
}
uint32_t size = (uint32_t) atoi(++p);
unsigned char abi_align = atoi(getToken(token, ":").c_str()) / 8;
unsigned char pref_align = atoi(getToken(token, ":").c_str()) / 8;
@ -529,6 +536,14 @@ unsigned char TargetData::getABITypeAlignment(const Type *Ty) const {
return getAlignment(Ty, true);
}
unsigned char TargetData::getCallFrameTypeAlignment(const Type *Ty) const {
for (unsigned i = 0, e = Alignments.size(); i != e; ++i)
if (Alignments[i].AlignType == STACK_ALIGN)
return Alignments[i].ABIAlign;
return getABITypeAlignment(Ty);
}
unsigned char TargetData::getPrefTypeAlignment(const Type *Ty) const {
return getAlignment(Ty, false);
}

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@ -146,7 +146,7 @@ public:
std::string getDataLayout() const {
const char *p;
if (is64Bit())
p = "e-p:64:64-f64:64:64-i64:64:64-f80:128:128";
p = "e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128";
else {
if (isTargetDarwin())
p = "e-p:32:32-f64:32:64-i64:32:64-f80:128:128";

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@ -0,0 +1,25 @@
; RUN: llvm-as < %s | llc -march=x86-64 | grep rep.movsl | count 2
%struct.s = type { i32, i32, i32, i32, i32, i32 }
define void @g(i32 %a1, i32 %a2, i32 %a3, i32 %a4, i32 %a5, i32 %a6) {
entry:
%d = alloca %struct.s, align 16
%tmp = getelementptr %struct.s* %d, i32 0, i32 0
store i32 %a1, i32* %tmp, align 16
%tmp2 = getelementptr %struct.s* %d, i32 0, i32 1
store i32 %a2, i32* %tmp2, align 16
%tmp4 = getelementptr %struct.s* %d, i32 0, i32 2
store i32 %a3, i32* %tmp4, align 16
%tmp6 = getelementptr %struct.s* %d, i32 0, i32 3
store i32 %a4, i32* %tmp6, align 16
%tmp8 = getelementptr %struct.s* %d, i32 0, i32 4
store i32 %a5, i32* %tmp8, align 16
%tmp10 = getelementptr %struct.s* %d, i32 0, i32 5
store i32 %a6, i32* %tmp10, align 16
call void @f( %struct.s* %d byval)
call void @f( %struct.s* %d byval)
ret void
}
declare void @f(%struct.s* byval)