llvm-6502/lib/Target/ARM/ARMInstrInfo.cpp
Chris Lattner d90183d25d Move the getInlineAsmLength virtual method from TAI to TII, where
the only real caller (GetFunctionSizeInBytes) uses it.

The custom ARM implementation of this is basically reimplementing
an assembler poorly for negligible gain.  It should be removed 
IMNSHO, but I'll leave that to ARMish folks to decide.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@77877 91177308-0d34-0410-b5e6-96231b3b80d8
2009-08-02 05:20:37 +00:00

262 lines
9.6 KiB
C++

//===- ARMInstrInfo.cpp - ARM Instruction Information -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the ARM implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "ARMInstrInfo.h"
#include "ARM.h"
#include "ARMAddressingModes.h"
#include "ARMGenInstrInfo.inc"
#include "ARMMachineFunctionInfo.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/LiveVariables.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/Target/TargetAsmInfo.h"
#include "llvm/Support/CommandLine.h"
using namespace llvm;
ARMInstrInfo::ARMInstrInfo(const ARMSubtarget &STI)
: RI(*this, STI), Subtarget(STI) {
}
unsigned ARMInstrInfo::getUnindexedOpcode(unsigned Opc) const {
switch (Opc) {
default: break;
case ARM::LDR_PRE:
case ARM::LDR_POST:
return ARM::LDR;
case ARM::LDRH_PRE:
case ARM::LDRH_POST:
return ARM::LDRH;
case ARM::LDRB_PRE:
case ARM::LDRB_POST:
return ARM::LDRB;
case ARM::LDRSH_PRE:
case ARM::LDRSH_POST:
return ARM::LDRSH;
case ARM::LDRSB_PRE:
case ARM::LDRSB_POST:
return ARM::LDRSB;
case ARM::STR_PRE:
case ARM::STR_POST:
return ARM::STR;
case ARM::STRH_PRE:
case ARM::STRH_POST:
return ARM::STRH;
case ARM::STRB_PRE:
case ARM::STRB_POST:
return ARM::STRB;
}
return 0;
}
bool ARMInstrInfo::BlockHasNoFallThrough(const MachineBasicBlock &MBB) const {
if (MBB.empty()) return false;
switch (MBB.back().getOpcode()) {
case ARM::BX_RET: // Return.
case ARM::LDM_RET:
case ARM::B:
case ARM::BR_JTr: // Jumptable branch.
case ARM::BR_JTm: // Jumptable branch through mem.
case ARM::BR_JTadd: // Jumptable branch add to pc.
return true;
default:
break;
}
return false;
}
void ARMInstrInfo::
reMaterialize(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DestReg, unsigned SubIdx,
const MachineInstr *Orig) const {
DebugLoc dl = Orig->getDebugLoc();
if (Orig->getOpcode() == ARM::MOVi2pieces) {
RI.emitLoadConstPool(MBB, I, dl,
DestReg, SubIdx,
Orig->getOperand(1).getImm(),
(ARMCC::CondCodes)Orig->getOperand(2).getImm(),
Orig->getOperand(3).getReg());
return;
}
MachineInstr *MI = MBB.getParent()->CloneMachineInstr(Orig);
MI->getOperand(0).setReg(DestReg);
MBB.insert(I, MI);
}
/// Count the number of comma-separated arguments.
/// Do not try to detect errors.
static unsigned countArguments(const char* p,
const TargetAsmInfo &TAI) {
unsigned count = 0;
while (*p && isspace(*p) && *p != '\n')
p++;
count++;
while (*p && *p!='\n' &&
strncmp(p, TAI.getCommentString(),
strlen(TAI.getCommentString())) != 0) {
if (*p==',')
count++;
p++;
}
return count;
}
/// Count the length of a string enclosed in quote characters.
/// Do not try to detect errors.
static unsigned countString(const char *p) {
unsigned count = 0;
while (*p && isspace(*p) && *p!='\n')
p++;
if (!*p || *p != '\"')
return count;
while (*++p && *p != '\"')
count++;
return count;
}
/// ARM-specific version of TargetAsmInfo::getInlineAsmLength.
unsigned ARMInstrInfo::getInlineAsmLength(const char *s,
const TargetAsmInfo &TAI) const {
// Make a lowercase-folded version of s for counting purposes.
char *q, *s_copy = (char *)malloc(strlen(s) + 1);
strcpy(s_copy, s);
for (q=s_copy; *q; q++)
*q = tolower(*q);
const char *Str = s_copy;
// Count the number of bytes in the asm.
bool atInsnStart = true;
bool inTextSection = true;
unsigned Length = 0;
for (; *Str; ++Str) {
if (atInsnStart) {
// Skip whitespace
while (*Str && isspace(*Str) && *Str != '\n')
Str++;
// Skip label
for (const char* p = Str; *p && !isspace(*p); p++)
if (*p == ':') {
Str = p+1;
while (*Str && isspace(*Str) && *Str != '\n')
Str++;
break;
}
if (*Str == 0) break;
// Ignore everything from comment char(s) to EOL
if (strncmp(Str, TAI.getCommentString(),
strlen(TAI.getCommentString())) == 0)
atInsnStart = false;
// FIXME do something like the following for non-Darwin
else if (*Str == '.' && Subtarget.isTargetDarwin()) {
// Directive.
atInsnStart = false;
// Some change the section, but don't generate code.
if (strncmp(Str, ".literal4", strlen(".literal4"))==0 ||
strncmp(Str, ".literal8", strlen(".literal8"))==0 ||
strncmp(Str, ".const", strlen(".const"))==0 ||
strncmp(Str, ".constructor", strlen(".constructor"))==0 ||
strncmp(Str, ".cstring", strlen(".cstring"))==0 ||
strncmp(Str, ".data", strlen(".data"))==0 ||
strncmp(Str, ".destructor", strlen(".destructor"))==0 ||
strncmp(Str, ".fvmlib_init0", strlen(".fvmlib_init0"))==0 ||
strncmp(Str, ".fvmlib_init1", strlen(".fvmlib_init1"))==0 ||
strncmp(Str, ".mod_init_func", strlen(".mod_init_func"))==0 ||
strncmp(Str, ".mod_term_func", strlen(".mod_term_func"))==0 ||
strncmp(Str, ".picsymbol_stub", strlen(".picsymbol_stub"))==0 ||
strncmp(Str, ".symbol_stub", strlen(".symbol_stub"))==0 ||
strncmp(Str, ".static_data", strlen(".static_data"))==0 ||
strncmp(Str, ".section", strlen(".section"))==0 ||
strncmp(Str, ".lazy_symbol_pointer", strlen(".lazy_symbol_pointer"))==0 ||
strncmp(Str, ".non_lazy_symbol_pointer", strlen(".non_lazy_symbol_pointer"))==0 ||
strncmp(Str, ".dyld", strlen(".dyld"))==0 ||
strncmp(Str, ".const_data", strlen(".const_data"))==0 ||
strncmp(Str, ".objc", strlen(".objc"))==0 || //// many directives
strncmp(Str, ".static_const", strlen(".static_const"))==0)
inTextSection=false;
else if (strncmp(Str, ".text", strlen(".text"))==0)
inTextSection = true;
// Some can't really be handled without implementing significant pieces
// of an assembler. Others require dynamic adjustment of block sizes in
// AdjustBBOffsetsAfter; it's a big compile-time speed hit to check every
// instruction in there, and none of these are currently used in the kernel.
else if (strncmp(Str, ".macro", strlen(".macro"))==0 ||
strncmp(Str, ".if", strlen(".if"))==0 ||
strncmp(Str, ".align", strlen(".align"))==0 ||
strncmp(Str, ".fill", strlen(".fill"))==0 ||
strncmp(Str, ".space", strlen(".space"))==0 ||
strncmp(Str, ".zerofill", strlen(".zerofill"))==0 ||
strncmp(Str, ".p2align", strlen(".p2align"))==0 ||
strncmp(Str, ".p2alignw", strlen(".p2alignw"))==0 ||
strncmp(Str, ".p2alignl", strlen(".p2alignl"))==0 ||
strncmp(Str, ".align32", strlen(".p2align32"))==0 ||
strncmp(Str, ".include", strlen(".include"))==0)
cerr << "Directive " << Str << " in asm may lead to invalid offsets for" <<
" constant pools (the assembler will tell you if this happens).\n";
// Some generate code, but this is only interesting in the text section.
else if (inTextSection) {
if (strncmp(Str, ".long", strlen(".long"))==0)
Length += 4*countArguments(Str+strlen(".long"), TAI);
else if (strncmp(Str, ".short", strlen(".short"))==0)
Length += 2*countArguments(Str+strlen(".short"), TAI);
else if (strncmp(Str, ".byte", strlen(".byte"))==0)
Length += 1*countArguments(Str+strlen(".byte"), TAI);
else if (strncmp(Str, ".single", strlen(".single"))==0)
Length += 4*countArguments(Str+strlen(".single"), TAI);
else if (strncmp(Str, ".double", strlen(".double"))==0)
Length += 8*countArguments(Str+strlen(".double"), TAI);
else if (strncmp(Str, ".quad", strlen(".quad"))==0)
Length += 16*countArguments(Str+strlen(".quad"), TAI);
else if (strncmp(Str, ".ascii", strlen(".ascii"))==0)
Length += countString(Str+strlen(".ascii"));
else if (strncmp(Str, ".asciz", strlen(".asciz"))==0)
Length += countString(Str+strlen(".asciz"))+1;
}
} else if (inTextSection) {
// An instruction
atInsnStart = false;
if (Subtarget.isThumb()) { // FIXME thumb2
// BL and BLX <non-reg> are 4 bytes, all others 2.
if (strncmp(Str, "blx", strlen("blx"))==0) {
const char* p = Str+3;
while (*p && isspace(*p))
p++;
if (*p == 'r' || *p=='R')
Length += 2; // BLX reg
else
Length += 4; // BLX non-reg
} else if (strncmp(Str, "bl", strlen("bl"))==0)
Length += 4; // BL
else
Length += 2; // Thumb anything else
}
else
Length += 4; // ARM
}
}
if (*Str == '\n' || *Str == TAI.getSeparatorChar())
atInsnStart = true;
}
free(s_copy);
return Length;
}