Remove the word "thumb" from comments. Remove also an incorrect

command regarding the porting from the ARM version (was an old comment).

llvm-svn: 194066
This commit is contained in:
Reed Kotler 2013-11-05 12:04:37 +00:00
parent 09f34ca4b9
commit d0caa24ad9

@ -9,9 +9,7 @@
//
//
// This pass is used to make Pc relative loads of constants.
// For now, only Mips16 will use this. While it has the same name and
// uses many ideas from the LLVM ARM Constant Island Pass, it's not intended
// to reuse any of the code from the ARM version.
// For now, only Mips16 will use this.
//
// Loading constants inline is expensive on Mips16 and it's in general better
// to place the constant nearby in code space and then it can be loaded with a
@ -783,10 +781,6 @@ unsigned MipsConstantIslands::getUserOffset(CPUser &U) const {
// Make sure U.getMaxDisp() returns a constrained range.
U.KnownAlignment = (KnownBits >= 2);
// On Thumb, offsets==2 mod 4 are rounded down by the hardware for
// purposes of the displacement computation; compensate for that here.
// For unknown alignments, getMaxDisp() constrains the range instead.
return UserOffset;
}
@ -1115,8 +1109,8 @@ static inline unsigned getUnconditionalBrDisp(int Opc) {
/// findAvailableWater - Look for an existing entry in the WaterList in which
/// we can place the CPE referenced from U so it's within range of U's MI.
/// Returns true if found, false if not. If it returns true, WaterIter
/// is set to the WaterList entry. For Thumb, prefer water that will not
/// introduce padding to water that will. To ensure that this pass
/// is set to the WaterList entry.
/// To ensure that this pass
/// terminates, the CPE location for a particular CPUser is only allowed to
/// move to a lower address, so search backward from the end of the list and
/// prefer the first water that is in range.
@ -1175,9 +1169,7 @@ void MipsConstantIslands::createNewWater(unsigned CPUserIndex,
const BasicBlockInfo &UserBBI = BBInfo[UserMBB->getNumber()];
// If the block does not end in an unconditional branch already, and if the
// end of the block is within range, make new water there. (The addition
// below is for the unconditional branch we will be adding: 4 bytes on ARM +
// Thumb2, 2 on Thumb1.
// end of the block is within range, make new water there.
if (BBHasFallthrough(UserMBB)) {
// Size of branch to insert.
unsigned Delta = 2;
@ -1204,17 +1196,7 @@ void MipsConstantIslands::createNewWater(unsigned CPUserIndex,
}
}
// What a big block. Find a place within the block to split it. This is a
// little tricky on Thumb1 since instructions are 2 bytes and constant pool
// entries are 4 bytes: if instruction I references island CPE, and
// instruction I+1 references CPE', it will not work well to put CPE as far
// forward as possible, since then CPE' cannot immediately follow it (that
// location is 2 bytes farther away from I+1 than CPE was from I) and we'd
// need to create a new island. So, we make a first guess, then walk through
// the instructions between the one currently being looked at and the
// possible insertion point, and make sure any other instructions that
// reference CPEs will be able to use the same island area; if not, we back
// up the insertion point.
// What a big block. Find a place within the block to split it.
// Try to split the block so it's fully aligned. Compute the latest split
// point where we can add a 4-byte branch instruction, and then align to
@ -1228,7 +1210,7 @@ void MipsConstantIslands::createNewWater(unsigned CPUserIndex,
BaseInsertOffset));
// The 4 in the following is for the unconditional branch we'll be inserting
// (allows for long branch on Thumb1). Alignment of the island is handled
// Alignment of the island is handled
// inside isOffsetInRange.
BaseInsertOffset -= 4;