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authorGabe Black <gblack@eecs.umich.edu>2010-06-02 12:58:17 -0500
committerGabe Black <gblack@eecs.umich.edu>2010-06-02 12:58:17 -0500
commitba7a7b0394d90dd369c65f1ac0869e0ae3f4b644 (patch)
tree070e97f024535f3b03a5d217440be0115e0dfbc6 /src/arch/arm/predecoder.hh
parent358fdc2a40e8a455f508532b47e55f3252053805 (diff)
downloadgem5-ba7a7b0394d90dd369c65f1ac0869e0ae3f4b644.tar.xz
ARM: Move some predecoder stuff into a .cc file.
--HG-- rename : src/arch/arm/predecoder.hh => src/arch/arm/predecoder.cc
Diffstat (limited to 'src/arch/arm/predecoder.hh')
-rw-r--r--src/arch/arm/predecoder.hh113
1 files changed, 6 insertions, 107 deletions
diff --git a/src/arch/arm/predecoder.hh b/src/arch/arm/predecoder.hh
index f146c30f4..2db550024 100644
--- a/src/arch/arm/predecoder.hh
+++ b/src/arch/arm/predecoder.hh
@@ -46,7 +46,7 @@
#define __ARCH_ARM_PREDECODER_HH__
#include "arch/arm/types.hh"
-#include "base/misc.hh"
+#include "arch/arm/miscregs.hh"
#include "base/types.hh"
class ThreadContext;
@@ -83,119 +83,18 @@ namespace ArmISA
return tc;
}
- void setTC(ThreadContext * _tc)
+ void
+ setTC(ThreadContext * _tc)
{
tc = _tc;
}
- void advanceThumbCond()
- {
- uint8_t condMask = itstate.mask;
- uint8_t thumbCond = itstate.cond;
- DPRINTF(Predecoder, "Advancing ITSTATE from %#x, %#x.\n",
- thumbCond, condMask);
- condMask = condMask << 1;
- uint8_t newBit = bits(condMask, 4);
- condMask &= mask(4);
- if (condMask == 0) {
- thumbCond = 0;
- } else {
- replaceBits(thumbCond, 0, newBit);
- }
- DPRINTF(Predecoder, "Advancing ITSTATE to %#x, %#x.\n",
- thumbCond, condMask);
- itstate.mask = condMask;
- itstate.cond = thumbCond;
- }
-
- void process()
- {
- if (!emi.thumb) {
- emi.instBits = data;
- emi.sevenAndFour = bits(data, 7) && bits(data, 4);
- emi.isMisc = (bits(data, 24, 23) == 0x2 &&
- bits(data, 20) == 0);
- DPRINTF(Predecoder, "Arm inst: %#x.\n", (uint64_t)emi);
- } else {
- uint16_t word = (data >> (offset * 8));
- if (bigThumb) {
- // A 32 bit thumb inst is half collected.
- emi.instBits = emi.instBits | word;
- bigThumb = false;
- offset += 2;
- DPRINTF(Predecoder, "Second half of 32 bit Thumb: %#x.\n",
- emi.instBits);
- if (itstate.mask) {
- emi.itstate = itstate;
- advanceThumbCond();
- emi.newItstate = itstate;
- }
- } else {
- uint16_t highBits = word & 0xF800;
- if (highBits == 0xE800 || highBits == 0xF000 ||
- highBits == 0xF800) {
- // The start of a 32 bit thumb inst.
- emi.bigThumb = 1;
- if (offset == 0) {
- // We've got the whole thing.
- emi.instBits = (data >> 16) | (data << 16);
- DPRINTF(Predecoder, "All of 32 bit Thumb: %#x.\n",
- emi.instBits);
- offset += 4;
- if (itstate.mask) {
- emi.itstate = itstate;
- advanceThumbCond();
- emi.newItstate = itstate;
- }
- } else {
- // We only have the first half word.
- DPRINTF(Predecoder,
- "First half of 32 bit Thumb.\n");
- emi.instBits = (uint32_t)word << 16;
- bigThumb = true;
- offset += 2;
- }
- } else {
- // A 16 bit thumb inst.
- offset += 2;
- emi.instBits = word;
- // Set the condition code field artificially.
- emi.condCode = COND_UC;
- DPRINTF(Predecoder, "16 bit Thumb: %#x.\n",
- emi.instBits);
- if (bits(word, 15, 8) == 0xbf &&
- bits(word, 3, 0) != 0x0) {
- emi.itstate = itstate;
- itstate = bits(word, 7, 0);
- emi.newItstate = itstate;
- DPRINTF(Predecoder,
- "IT detected, cond = %#x, mask = %#x\n",
- itstate.cond, itstate.mask);
- } else if (itstate.mask) {
- emi.itstate = itstate;
- advanceThumbCond();
- emi.newItstate = itstate;
- }
- }
- }
- }
- }
+ void advanceThumbCond();
+ void process();
//Use this to give data to the predecoder. This should be used
//when there is control flow.
- void moreBytes(Addr pc, Addr fetchPC, MachInst inst)
- {
- data = inst;
- offset = (fetchPC >= pc) ? 0 : pc - fetchPC;
- emi.thumb = (pc & (ULL(1) << PcTBitShift)) ? 1 : 0;
- FPSCR fpscr = tc->readMiscReg(MISCREG_FPSCR);
- emi.fpscrLen = fpscr.len;
- emi.fpscrStride = fpscr.stride;
- CPSR cpsr = tc->readMiscReg(MISCREG_CPSR);
- itstate.top6 = cpsr.it2;
- itstate.bottom2 = cpsr.it1;
- process();
- }
+ void moreBytes(Addr pc, Addr fetchPC, MachInst inst);
//Use this to give data to the predecoder. This should be used
//when instructions are executed in order.