Track the locations of local variables using EF_debug annotations.

SimplLocals:
- record locations of stack-allocated variables with annotations
  (of kind 5) at the beginning of the function;
- mark every assignment to non-stack-allocated variables with an
  annotation of kind 2.

Debugvar: (new pass!)
- perform availability analysis for debug annotations of kind 2
- insert "start of live range" and "end of live range" annotations
  (kind 3 and 4) to delimit intervals of PCs where the location
  of a local variable is known.

1 files changed, 5 insertions, 3 deletions

diff --git a/.depend b/.depend
index 4286b08c..889d6a1a 100644
--- a/.depend
+++ b/.depend
@@ -59,7 +59,7 @@ backend/ValueDomain.vo backend/ValueDomain.glob backend/ValueDomain.v.beautified
 $(ARCH)/ValueAOp.vo $(ARCH)/ValueAOp.glob $(ARCH)/ValueAOp.v.beautified: $(ARCH)/ValueAOp.v lib/Coqlib.vo driver/Compopts.vo common/AST.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/Memory.vo common/Globalenvs.vo $(ARCH)/Op.vo backend/ValueDomain.vo backend/RTL.vo
 backend/ValueAnalysis.vo backend/ValueAnalysis.glob backend/ValueAnalysis.v.beautified: backend/ValueAnalysis.v lib/Coqlib.vo lib/Maps.vo driver/Compopts.vo common/AST.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/Memory.vo common/Globalenvs.vo common/Events.vo lib/Lattice.vo backend/Kildall.vo backend/Registers.vo $(ARCH)/Op.vo backend/RTL.vo backend/ValueDomain.vo $(ARCH)/ValueAOp.vo backend/Liveness.vo lib/Axioms.vo
 $(ARCH)/ConstpropOp.vo $(ARCH)/ConstpropOp.glob $(ARCH)/ConstpropOp.v.beautified: $(ARCH)/ConstpropOp.v lib/Coqlib.vo driver/Compopts.vo common/AST.vo lib/Integers.vo lib/Floats.vo $(ARCH)/Op.vo backend/Registers.vo backend/ValueDomain.vo
-backend/Constprop.vo backend/Constprop.glob backend/Constprop.v.beautified: backend/Constprop.v lib/Coqlib.vo lib/Maps.vo common/AST.vo lib/Integers.vo lib/Floats.vo $(ARCH)/Op.vo $(ARCH)/Machregs.vo backend/Registers.vo backend/RTL.vo lib/Lattice.vo backend/Kildall.vo backend/Liveness.vo $(ARCH)/SelectOp.vo backend/ValueDomain.vo $(ARCH)/ValueAOp.vo backend/ValueAnalysis.vo $(ARCH)/ConstpropOp.vo
+backend/Constprop.vo backend/Constprop.glob backend/Constprop.v.beautified: backend/Constprop.v lib/Coqlib.vo lib/Maps.vo common/AST.vo lib/Integers.vo lib/Floats.vo $(ARCH)/Op.vo $(ARCH)/Machregs.vo backend/Registers.vo backend/RTL.vo lib/Lattice.vo backend/Kildall.vo backend/Liveness.vo backend/ValueDomain.vo $(ARCH)/ValueAOp.vo backend/ValueAnalysis.vo $(ARCH)/ConstpropOp.vo
 $(ARCH)/ConstpropOpproof.vo $(ARCH)/ConstpropOpproof.glob $(ARCH)/ConstpropOpproof.v.beautified: $(ARCH)/ConstpropOpproof.v lib/Coqlib.vo driver/Compopts.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/Memory.vo common/Globalenvs.vo common/Events.vo $(ARCH)/Op.vo backend/Registers.vo backend/RTL.vo backend/ValueDomain.vo $(ARCH)/ConstpropOp.vo
 backend/Constpropproof.vo backend/Constpropproof.glob backend/Constpropproof.v.beautified: backend/Constpropproof.v lib/Coqlib.vo lib/Maps.vo driver/Compopts.vo common/AST.vo lib/Integers.vo common/Values.vo common/Events.vo common/Memory.vo common/Globalenvs.vo common/Smallstep.vo $(ARCH)/Op.vo backend/Registers.vo backend/RTL.vo lib/Lattice.vo backend/Kildall.vo backend/ValueDomain.vo $(ARCH)/ValueAOp.vo backend/ValueAnalysis.vo $(ARCH)/ConstpropOp.vo backend/Constprop.vo $(ARCH)/ConstpropOpproof.vo
 backend/CSEdomain.vo backend/CSEdomain.glob backend/CSEdomain.v.beautified: backend/CSEdomain.v lib/Coqlib.vo lib/Maps.vo common/AST.vo common/Values.vo common/Memory.vo $(ARCH)/Op.vo backend/Registers.vo backend/RTL.vo
@@ -88,6 +88,8 @@ backend/Linearize.vo backend/Linearize.glob backend/Linearize.v.beautified: back
 backend/Linearizeproof.vo backend/Linearizeproof.glob backend/Linearizeproof.v.beautified: backend/Linearizeproof.v lib/Coqlib.vo lib/Maps.vo lib/Ordered.vo lib/Lattice.vo common/AST.vo lib/Integers.vo common/Values.vo common/Memory.vo common/Events.vo common/Globalenvs.vo common/Errors.vo common/Smallstep.vo $(ARCH)/Op.vo backend/Locations.vo backend/LTL.vo backend/Linear.vo backend/Linearize.vo
 backend/CleanupLabels.vo backend/CleanupLabels.glob backend/CleanupLabels.v.beautified: backend/CleanupLabels.v lib/Coqlib.vo lib/Ordered.vo backend/Linear.vo
 backend/CleanupLabelsproof.vo backend/CleanupLabelsproof.glob backend/CleanupLabelsproof.v.beautified: backend/CleanupLabelsproof.v lib/Coqlib.vo lib/Ordered.vo common/AST.vo lib/Integers.vo common/Values.vo common/Memory.vo common/Events.vo common/Globalenvs.vo common/Smallstep.vo $(ARCH)/Op.vo backend/Locations.vo backend/Linear.vo backend/CleanupLabels.vo
+backend/Debugvar.vo backend/Debugvar.glob backend/Debugvar.v.beautified: backend/Debugvar.v lib/Coqlib.vo lib/Axioms.vo lib/Maps.vo lib/Iteration.vo common/AST.vo lib/Integers.vo lib/Floats.vo common/Errors.vo $(ARCH)/Machregs.vo backend/Locations.vo backend/Conventions.vo backend/Linear.vo
+backend/Debugvarproof.vo backend/Debugvarproof.glob backend/Debugvarproof.v.beautified: backend/Debugvarproof.v lib/Coqlib.vo lib/Axioms.vo lib/Maps.vo lib/Iteration.vo common/AST.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/Memory.vo common/Events.vo common/Globalenvs.vo common/Smallstep.vo $(ARCH)/Op.vo common/Errors.vo $(ARCH)/Machregs.vo backend/Locations.vo backend/Conventions.vo backend/Linear.vo backend/Debugvar.vo
 backend/Mach.vo backend/Mach.glob backend/Mach.v.beautified: backend/Mach.v lib/Coqlib.vo lib/Maps.vo common/AST.vo lib/Integers.vo common/Values.vo common/Memory.vo common/Globalenvs.vo common/Events.vo common/Smallstep.vo $(ARCH)/Op.vo backend/Locations.vo backend/Conventions.vo $(ARCH)/Stacklayout.vo
 backend/Bounds.vo backend/Bounds.glob backend/Bounds.v.beautified: backend/Bounds.v lib/Coqlib.vo common/AST.vo $(ARCH)/Op.vo backend/Locations.vo backend/Linear.vo backend/Conventions.vo
 $(ARCH)/Stacklayout.vo $(ARCH)/Stacklayout.glob $(ARCH)/Stacklayout.v.beautified: $(ARCH)/Stacklayout.v lib/Coqlib.vo backend/Bounds.vo
@@ -112,7 +114,7 @@ cfrontend/SimplExprspec.vo cfrontend/SimplExprspec.glob cfrontend/SimplExprspec.
 cfrontend/SimplExprproof.vo cfrontend/SimplExprproof.glob cfrontend/SimplExprproof.v.beautified: cfrontend/SimplExprproof.v lib/Coqlib.vo lib/Maps.vo common/AST.vo common/Errors.vo lib/Integers.vo common/Values.vo common/Memory.vo common/Events.vo common/Smallstep.vo common/Globalenvs.vo cfrontend/Ctypes.vo cfrontend/Cop.vo cfrontend/Csyntax.vo cfrontend/Csem.vo cfrontend/Cstrategy.vo cfrontend/Clight.vo cfrontend/SimplExpr.vo cfrontend/SimplExprspec.vo
 cfrontend/Clight.vo cfrontend/Clight.glob cfrontend/Clight.v.beautified: cfrontend/Clight.v lib/Coqlib.vo common/Errors.vo lib/Maps.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/AST.vo common/Memory.vo common/Events.vo common/Globalenvs.vo common/Smallstep.vo cfrontend/Ctypes.vo cfrontend/Cop.vo
 cfrontend/ClightBigstep.vo cfrontend/ClightBigstep.glob cfrontend/ClightBigstep.v.beautified: cfrontend/ClightBigstep.v lib/Coqlib.vo lib/Maps.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/AST.vo common/Memory.vo common/Events.vo common/Globalenvs.vo common/Smallstep.vo cfrontend/Ctypes.vo cfrontend/Cop.vo cfrontend/Clight.vo
-cfrontend/SimplLocals.vo cfrontend/SimplLocals.glob cfrontend/SimplLocals.v.beautified: cfrontend/SimplLocals.v lib/Coqlib.vo lib/Ordered.vo common/Errors.vo common/AST.vo cfrontend/Ctypes.vo cfrontend/Cop.vo cfrontend/Clight.vo
+cfrontend/SimplLocals.vo cfrontend/SimplLocals.glob cfrontend/SimplLocals.v.beautified: cfrontend/SimplLocals.v lib/Coqlib.vo lib/Ordered.vo common/Errors.vo common/AST.vo cfrontend/Ctypes.vo cfrontend/Cop.vo cfrontend/Clight.vo driver/Compopts.vo
 cfrontend/SimplLocalsproof.vo cfrontend/SimplLocalsproof.glob cfrontend/SimplLocalsproof.v.beautified: cfrontend/SimplLocalsproof.v lib/Coqlib.vo common/Errors.vo lib/Ordered.vo common/AST.vo lib/Maps.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/Memory.vo common/Globalenvs.vo common/Events.vo common/Smallstep.vo cfrontend/Ctypes.vo cfrontend/Cop.vo cfrontend/Clight.vo cfrontend/SimplLocals.vo
 cfrontend/Cshmgen.vo cfrontend/Cshmgen.glob cfrontend/Cshmgen.v.beautified: cfrontend/Cshmgen.v lib/Coqlib.vo lib/Maps.vo common/Errors.vo lib/Integers.vo lib/Floats.vo common/AST.vo cfrontend/Ctypes.vo cfrontend/Cop.vo cfrontend/Clight.vo backend/Cminor.vo cfrontend/Csharpminor.vo
 cfrontend/Cshmgenproof.vo cfrontend/Cshmgenproof.glob cfrontend/Cshmgenproof.v.beautified: cfrontend/Cshmgenproof.v lib/Coqlib.vo common/Errors.vo lib/Maps.vo lib/Integers.vo lib/Floats.vo common/AST.vo common/Values.vo common/Events.vo common/Memory.vo common/Globalenvs.vo common/Smallstep.vo cfrontend/Ctypes.vo cfrontend/Cop.vo cfrontend/Clight.vo backend/Cminor.vo cfrontend/Csharpminor.vo cfrontend/Cshmgen.vo
@@ -120,7 +122,7 @@ cfrontend/Csharpminor.vo cfrontend/Csharpminor.glob cfrontend/Csharpminor.v.beau
 cfrontend/Cminorgen.vo cfrontend/Cminorgen.glob cfrontend/Cminorgen.v.beautified: cfrontend/Cminorgen.v lib/Coqlib.vo common/Errors.vo lib/Maps.vo lib/Ordered.vo common/AST.vo lib/Integers.vo lib/Floats.vo cfrontend/Csharpminor.vo backend/Cminor.vo
 cfrontend/Cminorgenproof.vo cfrontend/Cminorgenproof.glob cfrontend/Cminorgenproof.v.beautified: cfrontend/Cminorgenproof.v lib/Coqlib.vo lib/Intv.vo common/Errors.vo lib/Maps.vo common/AST.vo lib/Integers.vo lib/Floats.vo common/Values.vo common/Memory.vo common/Events.vo common/Globalenvs.vo common/Smallstep.vo common/Switch.vo cfrontend/Csharpminor.vo backend/Cminor.vo cfrontend/Cminorgen.vo
 driver/Compopts.vo driver/Compopts.glob driver/Compopts.v.beautified: driver/Compopts.v
-driver/Compiler.vo driver/Compiler.glob driver/Compiler.v.beautified: driver/Compiler.v lib/Coqlib.vo common/Errors.vo common/AST.vo common/Smallstep.vo cfrontend/Csyntax.vo cfrontend/Csem.vo cfrontend/Cstrategy.vo cfrontend/Cexec.vo cfrontend/Clight.vo cfrontend/Csharpminor.vo backend/Cminor.vo backend/CminorSel.vo backend/RTL.vo backend/LTL.vo backend/Linear.vo backend/Mach.vo $(ARCH)/Asm.vo cfrontend/Initializers.vo cfrontend/SimplExpr.vo cfrontend/SimplLocals.vo cfrontend/Cshmgen.vo cfrontend/Cminorgen.vo backend/Selection.vo backend/RTLgen.vo backend/Tailcall.vo backend/Inlining.vo backend/Renumber.vo backend/Constprop.vo backend/CSE.vo backend/Deadcode.vo backend/Unusedglob.vo backend/Allocation.vo backend/Tunneling.vo backend/Linearize.vo backend/CleanupLabels.vo backend/Stacking.vo $(ARCH)/Asmgen.vo cfrontend/SimplExprproof.vo cfrontend/SimplLocalsproof.vo cfrontend/Cshmgenproof.vo cfrontend/Cminorgenproof.vo backend/Selectionproof.vo backend/RTLgenproof.vo backend/Tailcallproof.vo backend/Inliningproof.vo backend/Renumberproof.vo backend/Constpropproof.vo backend/CSEproof.vo backend/Deadcodeproof.vo backend/Unusedglobproof.vo backend/Allocproof.vo backend/Tunnelingproof.vo backend/Linearizeproof.vo backend/CleanupLabelsproof.vo backend/Stackingproof.vo $(ARCH)/Asmgenproof.vo driver/Compopts.vo
+driver/Compiler.vo driver/Compiler.glob driver/Compiler.v.beautified: driver/Compiler.v lib/Coqlib.vo common/Errors.vo common/AST.vo common/Smallstep.vo cfrontend/Csyntax.vo cfrontend/Csem.vo cfrontend/Cstrategy.vo cfrontend/Cexec.vo cfrontend/Clight.vo cfrontend/Csharpminor.vo backend/Cminor.vo backend/CminorSel.vo backend/RTL.vo backend/LTL.vo backend/Linear.vo backend/Mach.vo $(ARCH)/Asm.vo cfrontend/Initializers.vo cfrontend/SimplExpr.vo cfrontend/SimplLocals.vo cfrontend/Cshmgen.vo cfrontend/Cminorgen.vo backend/Selection.vo backend/RTLgen.vo backend/Tailcall.vo backend/Inlining.vo backend/Renumber.vo backend/Constprop.vo backend/CSE.vo backend/Deadcode.vo backend/Unusedglob.vo backend/Allocation.vo backend/Tunneling.vo backend/Linearize.vo backend/CleanupLabels.vo backend/Debugvar.vo backend/Stacking.vo $(ARCH)/Asmgen.vo cfrontend/SimplExprproof.vo cfrontend/SimplLocalsproof.vo cfrontend/Cshmgenproof.vo cfrontend/Cminorgenproof.vo backend/Selectionproof.vo backend/RTLgenproof.vo backend/Tailcallproof.vo backend/Inliningproof.vo backend/Renumberproof.vo backend/Constpropproof.vo backend/CSEproof.vo backend/Deadcodeproof.vo backend/Unusedglobproof.vo backend/Allocproof.vo backend/Tunnelingproof.vo backend/Linearizeproof.vo backend/CleanupLabelsproof.vo backend/Debugvarproof.vo backend/Stackingproof.vo $(ARCH)/Asmgenproof.vo driver/Compopts.vo
 driver/Complements.vo driver/Complements.glob driver/Complements.v.beautified: driver/Complements.v lib/Coqlib.vo common/AST.vo lib/Integers.vo common/Values.vo common/Events.vo common/Globalenvs.vo common/Smallstep.vo common/Behaviors.vo cfrontend/Csyntax.vo cfrontend/Csem.vo cfrontend/Cstrategy.vo cfrontend/Clight.vo backend/Cminor.vo backend/RTL.vo $(ARCH)/Asm.vo driver/Compiler.vo common/Errors.vo
 flocq/Core/Fcore_Raux.vo flocq/Core/Fcore_Raux.glob flocq/Core/Fcore_Raux.v.beautified: flocq/Core/Fcore_Raux.v flocq/Core/Fcore_Zaux.vo
 flocq/Core/Fcore_Zaux.vo flocq/Core/Fcore_Zaux.glob flocq/Core/Fcore_Zaux.v.beautified: flocq/Core/Fcore_Zaux.v