wine/gecko
0
0
Fork 0
mirror of https://gitlab.winehq.org/wine/wine-gecko.git synced 2024-09-13 09:24:08 -07:00
Code Issues Packages Projects Releases Wiki Activity

Bug 1025011: Comment the difference between use* and use*AtStart during Lowering; (comments only: DONTBUILD) r=jandem

Browse Source
This commit is contained in:
Benjamin Bouvier 2014-06-16 14:57:26 +02:00
parent 4f9278d073
commit d13acbdb85
1 changed files with 19 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

24
js/src/jit/shared/Lowering-shared.h
View File

@ -66,6 +66,20 @@ class LIRGeneratorShared : public MInstructionVisitorWithDefaults
// These all create a use of a virtual register, with an optional
// allocation policy.
//
// Some of these use functions have atStart variants.
// - non-atStart variants will tell the register allocator that the input
// allocation must be different from any Temp or Definition also needed for
// this LInstruction.
// - atStart variants relax that restriction and allow the input to be in
// the same register as any Temp or output Definition used by the
// LInstruction. Note that it doesn't *imply* this will actually happen,
// but gives a hint to the register allocator that it can do it.
//
// TL;DR: Use non-atStart variants only if you need the input value after
// writing to any temp or definitions, during code generation of this
// LInstruction. Otherwise, use atStart variants, which will lower register
// pressure.
inline LUse use(MDefinition *mir, LUse policy);
inline LUse use(MDefinition *mir);
inline LUse useAtStart(MDefinition *mir);
@ -77,13 +91,13 @@ class LIRGeneratorShared : public MInstructionVisitorWithDefaults
inline LUse useFixedAtStart(MDefinition *mir, Register reg);
inline LAllocation useOrConstant(MDefinition *mir);
inline LAllocation useOrConstantAtStart(MDefinition *mir);
// "Any" is architecture dependent, and will include registers and stack slots on X86,
// and only registers on ARM.
// "Any" is architecture dependent, and will include registers and stack
// slots on X86, and only registers on ARM.
inline LAllocation useAny(MDefinition *mir);
inline LAllocation useAnyOrConstant(MDefinition *mir);
// "Storable" is architecture dependend, and will include registers and constants on X86
// and only registers on ARM.
// this is a generic "things we can expect to write into memory in 1 instruction"
// "Storable" is architecture dependend, and will include registers and
// constants on X86 and only registers on ARM. This is a generic "things
// we can expect to write into memory in 1 instruction".
inline LAllocation useStorable(MDefinition *mir);
inline LAllocation useStorableAtStart(MDefinition *mir);
inline LAllocation useKeepaliveOrConstant(MDefinition *mir);