SparcSubtarget.cpp revision dce4a407a24b04eebc6a376f8e62b41aaa7b071f 
1//===-- SparcSubtarget.cpp - SPARC Subtarget Information ------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements the SPARC specific subclass of TargetSubtargetInfo.
11//
12//===----------------------------------------------------------------------===//
13
14#include "SparcSubtarget.h"
15#include "Sparc.h"
16#include "llvm/Support/MathExtras.h"
17#include "llvm/Support/TargetRegistry.h"
18
19using namespace llvm;
20
21#define DEBUG_TYPE "sparc-subtarget"
22
23#define GET_SUBTARGETINFO_TARGET_DESC
24#define GET_SUBTARGETINFO_CTOR
25#include "SparcGenSubtargetInfo.inc"
26
27void SparcSubtarget::anchor() { }
28
29SparcSubtarget::SparcSubtarget(const std::string &TT, const std::string &CPU,
30                               const std::string &FS,  bool is64Bit) :
31  SparcGenSubtargetInfo(TT, CPU, FS),
32  IsV9(false),
33  V8DeprecatedInsts(false),
34  IsVIS(false),
35  Is64Bit(is64Bit),
36  HasHardQuad(false),
37  UsePopc(false) {
38
39  // Determine default and user specified characteristics
40  std::string CPUName = CPU;
41  if (CPUName.empty())
42    CPUName = (is64Bit) ? "v9" : "v8";
43
44  // Parse features string.
45  ParseSubtargetFeatures(CPUName, FS);
46
47  // Popc is a v9-only instruction.
48  if (!IsV9)
49    UsePopc = false;
50}
51
52
53int SparcSubtarget::getAdjustedFrameSize(int frameSize) const {
54
55  if (is64Bit()) {
56    // All 64-bit stack frames must be 16-byte aligned, and must reserve space
57    // for spilling the 16 window registers at %sp+BIAS..%sp+BIAS+128.
58    frameSize += 128;
59    // Frames with calls must also reserve space for 6 outgoing arguments
60    // whether they are used or not. LowerCall_64 takes care of that.
61    assert(frameSize % 16 == 0 && "Stack size not 16-byte aligned");
62  } else {
63    // Emit the correct save instruction based on the number of bytes in
64    // the frame. Minimum stack frame size according to V8 ABI is:
65    //   16 words for register window spill
66    //    1 word for address of returned aggregate-value
67    // +  6 words for passing parameters on the stack
68    // ----------
69    //   23 words * 4 bytes per word = 92 bytes
70    frameSize += 92;
71
72    // Round up to next doubleword boundary -- a double-word boundary
73    // is required by the ABI.
74    frameSize = RoundUpToAlignment(frameSize, 8);
75  }
76  return frameSize;
77}
78