Dynamically-scoped variables

3 files changed, 89 insertions, 0 deletions

diff --git a/compiler/elymasGlobalSys.ey b/compiler/elymasGlobalSys.ey
index 912d5c0..68a30c9 100644
--- a/compiler/elymasGlobalSys.ey
+++ b/compiler/elymasGlobalSys.ey
@@ -120,6 +120,7 @@
 
   "elymasGlobalSysAsm.ey" include
   "elymasGlobalSysOpt.ey" include
+  "elymasGlobalSysDyn.ey" include
   "elymasGlobalSysTyped.ey" include
 
   leaveSubScope
diff --git a/compiler/elymasGlobalSysDyn.ey b/compiler/elymasGlobalSysDyn.ey
new file mode 100644
index 0000000..0f1c542
--- /dev/null
+++ b/compiler/elymasGlobalSysDyn.ey
@@ -0,0 +1,83 @@
+# dynamic variables with stack
+<
+  "dyn" enterSubScope
+
+  5 ==DYNAMICVARIABLEMARKER
+
+  <
+    # get dynamic variable value
+    # 0 -> dynamic variable object
+    # 0 <- non-zero if a value is defined, zero otherwise
+    # 1 <- current value (if it exists)
+    [[
+      /rbx :popqReg
+
+      /rdx :popqReg
+      DYNAMICVARIABLEMARKER /rax :movqImmReg
+      :STACKBOTTOMMARKER /rcx :movqImmReg
+      /r15 /rsi :movqRegReg
+      8 /rsi :subqImm8Reg
+
+      @scanStack
+      8 /rsi :addqImm8Reg
+
+      /rsi /rax :cmpqMemReg
+      /dynamicVariableMarker :jzLbl8
+      /rsi /rcx :cmpqMemReg
+      /scanStack :jnzLbl8
+
+      # no value was found
+      /rax /rax :xorqRegReg
+      63 /rax :btsqImm8Reg
+      /rax :pushqReg
+
+      /rbx :pushqReg
+      :retn
+
+      @dynamicVariableMarker
+      8 /rsi /rdx :cmpqMemDisp8Reg
+      /scanStack :jnzLbl8 # wrong variable
+
+      16 /rsi :pushqMemDisp8
+      /rax /rax :xorqRegReg
+      /rax :incqReg
+      63 /rax :btsqImm8Reg
+      /rax :pushqReg
+
+      /rbx :pushqReg
+      :retn
+    ]] /eyget defv
+
+    # set dynamic variable and execute function
+    # 0 -> dynamic variable object
+    # 1 -> value to set
+    # 2 -> object to execute
+    [[
+      8 /r15 :subqImm8Reg
+      /r15 :popqMem
+
+      24 /r15 :subqImm8Reg
+      8 /r15 :popqMemDisp8
+      16 /r15 :popqMemDisp8
+      DYNAMICVARIABLEMARKER /rax :movqImmReg
+      /rax /r15 :movqRegMem
+
+      |ey* /rax :movqImmReg
+      /rax :callqReg
+
+      24 /r15 :addqImm8Reg
+      /r15 :pushqMem
+      8 /r15 :addqImm8Reg
+      :retn
+    ]] /eywith defv
+  > _ ==globalFunctions { defv }' ::allocateOffsetStruct
+
+  [
+    globalFunctions keys eydeff { | }' createScopeEntries
+    createScopeExtensionEntries
+  ] :execute
+
+  leaveSubScope
+> --
+
+# vim: syn=elymas
diff --git a/notes b/notes
index 1d0c2a6..f151b04 100644
--- a/notes
+++ b/notes
@@ -131,6 +131,11 @@ bottom of stack marker
 0000000000000000000000000000000000000000000000000000000000000100
 error data marker (only for external debugging)
 
+0000000000000000000000000000000000000000000000000000000000000101
+dynamic variable binding marker (call stack only)
+next two cells (upwards into the stack)
+* reference to dynamic variable object
+* reference to current value
 
 = Memory Management =