On Thu, Dec 17, 2015 at 10:42 AM, <commits@source.squeak.org> wrote:

Eliot Miranda uploaded a new version of VMMaker to project VM Maker:
http://source.squeak.org/VMMaker/VMMaker.oscog-eem.1609.mcz

==================== Summary ====================

Name: VMMaker.oscog-eem.1609
Author: eem
Time: 17 December 2015, 10:41:49.192 am
UUID: 771cdc25-5d27-4818-8943-2ba5c0e31791
Ancestors: VMMaker.oscog-eem.1608

Cogit: Fix the (arguably bogus) register save/restore code for safe trampolines, including the ceScheduleScavenge call.

=============== Diff against VMMaker.oscog-eem.1608 ===============

Item was added:
+ ----- Method: CogARMCompiler>>genSaveRegForCCall (in category 'abi') -----
+ genSaveRegForCCall
+�� "Save the general purpose registers for a call into the C run-time from a trampoline."
+�� "Save none, because the ARM ABI only defines callee saved registers, no caller-saved regs."
+�� "cogit gen: STMFD operand: 16r7F"!

Item was removed:
- ----- Method: CogARMCompiler>>genSaveRegisters (in category 'abi') -----
- genSaveRegisters
-�� "Save the general purpose registers for a trampoline call."
-�� "Save none, because the ARM ABI only defines callee saved registers, no caller-saved regs."
-�� "cogit gen: STMFD operand: 16r7F"!

Item was added:
+ ----- Method: CogARMCompiler>>genSaveRegsForCCall (in category 'abi') -----
+ genSaveRegsForCCall
+�� "Save the general purpose registers for a trampoline call."
+�� "Save none, because the ARM ABI only defines callee saved registers, no caller-saved regs."
+�� "cogit gen: STMFD operand: 16r7F"
+�� self flag: 'this will change with Sista when we hope to be able to allocate arbitrary registers'!

Item was removed:
- ----- Method: CogAbstractInstruction>>genSaveRegisters (in category 'abi') -----
- genSaveRegisters
-�� "Save the general purpose registers for a trampoline call."
-�� self subclassResponsibility!

Item was changed:
�� ----- Method: CogIA32Compiler>>genRestoreRegsExcept: (in category 'abi') -----
�� genRestoreRegsExcept: abstractReg
�� | realReg |
�� realReg := self concreteRegister: abstractReg.
�� self assert: (EDI > EAX and: [EDI - EAX + 1 = 6]).
�� EAX to: EDI do:
�� [:reg|
+�� (reg between: ESP and: EBP) ifFalse:
+�� [realReg = reg
+�� ifTrue: [cogit AddCq: 4 R: ESP]
+�� ifFalse: [cogit PopR: reg]]].
-�� realReg = reg ifTrue: [cogit AddCq: 4 R: ESP] ifFalse: [cogit PopR: reg]].
�� ^0!

Item was removed:
- ----- Method: CogIA32Compiler>>genSaveRegisters (in category 'abi') -----
- genSaveRegisters
-�� "Save the general purpose registers for a trampoline call."
-
-�� self assert: (EDI > EAX and: [EDI - EAX + 1 = 8]).
-�� EDI to: EAX by: -1 do:
-�� [:reg|
-�� (reg between: ESP and: EBP) ifFalse:
-�� [cogit PushR: reg]].
-�� ^0!

Item was added:
+ ----- Method: CogIA32Compiler>>genSaveRegsForCCall (in category 'abi') -----
+ genSaveRegsForCCall
+�� "Save the general purpose registers for a call into the C run-time from a trampoline."
+
+�� self assert: (EDI > EAX and: [EDI - EAX + 1 = 8]).
+�� EDI to: EAX by: -1 do:
+�� [:reg|
+�� (reg between: ESP and: EBP) ifFalse:
+�� [cogit PushR: reg]].
+�� ^0!

Item was removed:
- ----- Method: CogMIPSELCompiler>>genSaveRegisters (in category 'abi') -----
- genSaveRegisters
-�� "This method is poorly named. Is this for a Smalltalk -> C call or C -> Smalltalk call?
-�� If the former we don't need to do anything because all of the abstract registers are
-�� allocated to C preserved registers."
-�� self flag: #bogus.!

Item was added:
+ ----- Method: CogMIPSELCompiler>>genSaveRegsForCCall (in category 'abi') -----
+ genSaveRegsForCCall
+�� "Save the general purpose registers for a call into the C run-time from a trampoline.
+�� We don't need to do anything because all of the abstract registers are
+�� allocated to C preserved registers."
+�� self flag: 'this will change with Sista when we hope to be able to allocate arbitrary registers'!

Item was changed:
�� ----- Method: CogX64Compiler>>genRestoreRegs (in category 'abi') -----
�� genRestoreRegs
�� "Restore the general purpose registers for a trampoline call.
�� c.f. genSaveRegisters"
+�� RAX to: R15 do:
+�� [:reg|
+�� (reg between: RSP and: RBP) ifFalse:
+�� [cogit PopR: reg]].
-�� cogit
-�� PopR: RAX;
-�� PopR: RBX;
-�� PopR: RCX;
-�� PopR: RDX;
-�� PopR: RSI;
-�� PopR: RDI;
-�� PopR: R8;
-�� PopR: R9;
-�� PopR: R10;
-�� PopR: R11;
-�� PopR: R12;
-�� PopR: R13;
-�� PopR: R14;
-�� PopR: R15.
�� ^0!

Item was changed:
�� ----- Method: CogX64Compiler>>genRestoreRegsExcept: (in category 'abi') -----
�� genRestoreRegsExcept: abstractReg
�� | realReg |
�� realReg := self concreteRegister: abstractReg.
�� self assert: (R15 > RAX and: [R15 - RAX + 1 = 16]).
�� RAX to: R15 do:
�� [:reg|
+�� (reg between: RSP and: RBP) ifFalse:
+�� [realReg = reg
+�� ifTrue: [cogit AddCq: 8 R: RSP]
+�� ifFalse: [cogit PopR: reg]]].
-�� realReg = reg ifTrue: [cogit AddCq: 4 R: RSP] ifFalse: [cogit PopR: reg]].
�� ^0!

Item was removed:
- ----- Method: CogX64Compiler>>genSaveRegisters (in category 'abi') -----
- genSaveRegisters
-�� "Save the general purpose registers for a trampoline call."
-
-�� self assert: (R15 > RAX and: [R15 - RAX + 1 = 16]).
-�� R15 to: RAX by: -1 do: [:reg| cogit PushR: reg].
-�� ^0!

Item was added:
+ ----- Method: CogX64Compiler>>genSaveRegsForCCall (in category 'abi') -----
+ genSaveRegsForCCall
+�� "Save the general purpose registers for a trampoline call."
+
+�� self assert: (R15 > RAX and: [R15 - RAX + 1 = 16]).
+�� R15 to: RAX by: -1 do:
+�� [:reg|
+�� (reg between: RSP and: RBP) ifFalse:
+�� [cogit PushR: reg]].
+�� ^0!

Item was changed:
�� ----- Method: Cogit>>compileCallFor:numArgs:arg:arg:arg:arg:resultReg:saveRegs: (in category 'initialization') -----
�� compileCallFor: aRoutine numArgs: numArgs arg: regOrConst0 arg: regOrConst1 arg: regOrConst2 arg: regOrConst3 resultReg: resultRegOrNone saveRegs: saveRegs
�� "Generate a call to aRoutine with up to 4 arguments.�� If resultRegOrNone is not
�� NoReg assign the C result to resultRegOrNone.�� If saveRegs, save all registers.
�� Hack: a negative arg value indicates an abstract register, a non-negative value
�� indicates a constant."
�� <var: #aRoutine type: #'void *'>
�� <inline: false>
�� cStackAlignment > objectMemory wordSize ifTrue:
�� [backEnd
�� genAlignCStackSavingRegisters: saveRegs
�� numArgs: numArgs
�� wordAlignment: cStackAlignment / objectMemory wordSize].
�� saveRegs ifTrue:
+�� [backEnd genSaveRegsForCCall].
-�� [backEnd genSaveRegisters].
�� backEnd genMarshallNArgs: numArgs arg: regOrConst0 arg: regOrConst1 arg: regOrConst2 arg: regOrConst3.
�� self CallFullRT: (self cCode: [aRoutine asUnsignedInteger]
�� inSmalltalk: [self simulatedTrampolineFor: aRoutine]).
�� resultRegOrNone ~= NoReg ifTrue:
�� [backEnd genWriteCResultIntoReg: resultRegOrNone].
�� saveRegs ifTrue:
�� [numArgs > 0 ifTrue:
�� [backEnd genRemoveNArgsFromStack: numArgs].
�� resultRegOrNone ~= NoReg
�� ifTrue: [backEnd genRestoreRegsExcept: resultRegOrNone]
�� ifFalse: [backEnd genRestoreRegs]]!

_,,,^..^,,,_

best,��Eliot