Handle more than 64 registers - Part 4 #102921
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This reverts commit d53b620. By not passing `regMaskTP` using constant reference, there is a small cost we have to pay: Without constant reference: Overall: 1.80% MinOpts: 2.05% FullOpts: 1.62% With constant reference: Overall: 1.74% MinOpts: 1.94% FullOpts: 1.6%
Moved the *= operators as instance of `regMaskTP` so the `.low` private field can directly be manipulated instead of converting the `64-bit` value in `regMaskTP` before doing any operation. Overall: 0.74% MinOpts: 0.82% FullOpts: 0.68%
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@dotnet/jit-contrib @jakobbotsch PTAL |
| #endif // TARGET_XARCH | ||
| } | ||
| #ifdef TARGET_ARM | ||
| if (call->IsVirtualStub()) | ||
| { | ||
| killMask |= compiler->virtualStubParamInfo->GetRegMask(); | ||
| killMask.AddGprRegs(compiler->virtualStubParamInfo->GetRegMask()); |
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Why is this using AddGprRegs? Isn't virtualStubParamInfo->GetRegMask() returning a regMaskTP?
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The GetRegMask() returns _regMask_enum which is uint64_t. So this was the simplest thing to do ATM
| @@ -911,15 +919,15 @@ regMaskTP LinearScan::getKillSetForBlockStore(GenTreeBlk* blkNode) | |||
| if (isCopyBlk) | |||
| { | |||
| // rep movs kills RCX, RDI and RSI | |||
| killMask = RBM_RCX | RBM_RDI | RBM_RSI; | |||
| killMask.AddGprRegs(RBM_RCX | RBM_RDI | RBM_RSI); | |||
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Aren't RBM_* regMaskTP already? I don't really understand changes here (in multiple places it seems like we shouldn't need to switch to SingleRegTypeMask overloads)
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yes, all the RBM_* are still uint64_t except for allAvailableRegs. Here is what I am planning to do after this PR:
- Send a PR that convert the
killMask's registerAssignment toregMaskTP(by unioning existing field or equivalent) - I am still deciding if we should convert all or just subset of
RBM_*, but most likely I will convert just someRBM_*toregMaskTPthat contains mask. All the remaining can continue to beuint64_t. In future, if we feel a need for TP improvement reason, we can convert them all toregMaskTP(once predicate register work is complete).
| SingleTypeRegSet value = genSingleTypeRegMask(reg); | ||
| #ifdef HAS_MORE_THAN_64_REGISTERS | ||
| if (reg < 64) | ||
| { | ||
| low |= value; | ||
| } | ||
| else | ||
| { | ||
| high |= value; | ||
| } |
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Would it be more efficient to inline the computation of value in the "else" case as reg - 64?
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The mask value for registers > 63, will anyway start from 0x0, so it should be fine, the way we are doing currently.
| @@ -305,56 +364,69 @@ struct regMaskTP | |||
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| SingleTypeRegSet GetPredicateRegSet() const | |||
| { | |||
| #ifdef HAS_MORE_THAN_64_REGISTERS | |||
| return getHigh(); | |||
| #else | |||
| return getLow(); | |||
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Shouldn't it be getLow() >> REG_P0 or something like that?
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For x64, when we create the RBM_ALLMASK, we already have bits set to 0 except the ones that represent mask registers, hence should be safe to just return getLow().
| }; | ||
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| static regMaskTP operator^(regMaskTP first, regMaskTP second) | ||
| static regMaskTP operator^(const regMaskTP& first, const regMaskTP& second) |
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Does this make a difference?
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don't think so. I just wanted to make it consistent like other methods.
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Do you know what's up with the linux-x64 TP diffs? We don't define Can you post the detailed TP diff after your latest changes? |
yes, that's a good question. Let me see the numbers with latest round and debug from there.
Will do. |
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It's similar to what I posted in #102921 (comment). This is for overall collection, but for MinOpts, the |
as we saw offline, this is the fact that our linux builds are not link time optimization enabled and hence give the difference because of new methods like |
allocateRegistersMinimalbulk of difference is coming from the fact that we are updating
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If I remove
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#103058 should fix that. Let me know if you have more comments or is this good to go. |
| #if defined(TARGET_XARCH) | ||
| killMask &= ~(RBM_FLT_CALLEE_TRASH | RBM_MSK_CALLEE_TRASH); | ||
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| #ifdef TARGET_AMD64 | ||
| killMask.RemoveRegsetForType(RBM_FLT_CALLEE_TRASH.getLow(), FloatRegisterType); | ||
| killMask.RemoveRegsetForType(RBM_MSK_CALLEE_TRASH.getLow(), MaskRegisterType); | ||
| #else | ||
| killMask &= ~RBM_FLT_CALLEE_TRASH; | ||
| killMask.RemoveRegsetForType(RBM_FLT_CALLEE_TRASH, FloatRegisterType); | ||
| killMask &= ~RBM_MSK_CALLEE_TRASH; | ||
| #endif // TARGET_AMD64 | ||
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| #else | ||
| killMask.RemoveRegsetForType(RBM_FLT_CALLEE_TRASH, FloatRegisterType); |
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I guess this will change back to what it was before once we change RBM_* to be regMaskTP?
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I don't want to block on it, but I guess it would be nice to make the RBM_* change first, since it seems a lot of the changes of this PR end up having to deal with the fact that RBM_* aren't regMaskTP.
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Sure, there are few places that we have to do, but at this point I think I will go ahead and merge this PR as-is and probably start working on RBM_ change next.
Opened #103079 |
This adds
highfield inregMaskTPunderHAS_MORE_THAN_64_REGISTERSand update various code paths to should take into account querying or updating this field.I have made commits that are isolated, so putting here for reference for ease review.
[ 6f07fc3 ] (HEAD -> part4, kp/part4) jit format
[ 95ca449 ] genRegNumFromMask() to take SingleTypeRegSet
[ 7de39e7 ] Add assert in genFindLowestBit() and genMaxOneBit() to be only applicable for gpr/float
[ fb0c4ca ] bug fix
[ c72147f ] Initialize regMaskTP in genRegMask()
[ edccae2 ] Change some more methods to return SingleTypeRegMask
[ cedb079 ] Add various variants of genRegNumFromMask() and use them
[ 8b7084a ] Move registerType in Referencable, add getRegisterType()
[ 3741ac6 ] Move mapTypeToRegTypeIndex() and mapRegNumtoRegTypeIndex() in compiler.hpp
[ 687ed43 ] Add operator[]
[ b2d9b1c ] jit format
[ e56dc9b ] fix some other build failures
[ 5f63e60 ] misc cleanup
[ 7542417 ] operators() that operate on regNum
[ 2d1d2bb ] GetRegSetForType() defintion
[ d14f56a ] RemoveRegsetForType()
[ 147a88b ] AddRegsetForType()
[ 535c2e1 ] AddGprRegs()
[ 1d0f492 ] IsRegNumInMask() and IsRegNumPresent()
[ f370cf1 ] Use IsEmpty() and IsNonEmpty()
[ fd18c7f ] RemoveRegNumFromMask() and RemoveRegNum() and consume them
[ ed203f3 ] Use AddRegNumInMask() and AddRegNum()
[ c192d95 ] AddRegNumInMask/AddRegNum
[ a38460a ] change the structure of regMaskTP for performance
[ 4fe1caa ] Add regTypeTag in register*.h files
[ 27b8170 ] Use HAS_MORE_THAN_64_REGISTERS macro
[ 6ffccb3 ] Make high only to arm64
[ fed5c2a ] use genSingleTypeRegMask()
[ b4b08fa ] Add high to all platforms
[ 53c29d1 ] jit fornat
[ ccddf1c ] Furture reduce the TP cost
[ b3218e1 ] Revert "Do not use
const regMaskTP&as parameter"[ 78b34fa ] Do not use
const regMaskTP&as parameter[ e895528 ] Add high field