rewrite overrides, reimplement ROL/ROR

example.lua

@@ -1,6 +1,6 @@
 package.path = package.path..";?/init.lua"
 local lips = require "lips"
-local err = lips('example.asm', nil, {offset=0})
+local err = lips('example.asm')
 if err then
     print(err)
 end

lips/Dumper.lua

@@ -45,7 +45,7 @@ end
 
 function Dumper:desym(t)
     if t.tt == 'REL' then
-        return self:label_delta(self:pc(), t.tok)
+        return t.tok
     elseif type(t.tok) == 'number' then
         if t.offset then
             return t.tok + t.offset

lips/init.lua

@@ -53,6 +53,7 @@ function lips.assemble(fn_or_asm, writer, options)
             options.origin = options.offset
             options.base = 0
         else
+            options.origin = options.origin or 0
             options.base = options.base or 0x80000000
         end
 

lips/overrides.lua

@@ -8,7 +8,7 @@ local overrides = {}
 
 local function tob_override(self, name)
     -- handle all the addressing modes for lw/sw-like instructions
-    local rt = self:pop('CPU')
+    local dest = self:pop('CPU')
     local offset, base
     if self:peek('DEREF') then
         offset = 0
@@ -28,12 +28,12 @@ local function tob_override(self, name)
         end
         -- attempt to use the fewest possible instructions for this offset
         if not o.portion and (o.tt == 'LABELSYM' or o.tok >= 0x80000000) then
-            local immediate = self:token(o):set('portion', 'upperoff')
+            local temp = self:token(o):set('portion', 'upperoff')
-            self:push_new('LUI', 'AT', immediate)
+            self:push_new('LUI', 'AT', temp)
             if self.s[self.i] ~= nil then
                 local reg = self:pop('DEREF'):set('tt', 'REG')
                 if reg.tok ~= 'R0' then
-                    self:push_new('ADDU', 'AT', 'AT', 'R0')
+                    self:push_new('ADDU', 'AT', 'AT', reg)
                 end
             end
             base = self:token('DEREF', 'AT')
@@ -41,7 +41,7 @@ local function tob_override(self, name)
             base = self:pop('DEREF')
         end
     end
-    self:push_new(name, rt, offset, base)
+    self:push_new(name, dest, offset, base)
 end
 
 for k, v in pairs(data.instructions) do
@@ -50,8 +50,8 @@ for k, v in pairs(data.instructions) do
     end
 end
 
-function overrides.LI(self, name)
+function overrides:LI(name)
-    local rt = self:pop('CPU')
+    local dest = self:pop('CPU')
     local im = self:pop('CONST')
 
     -- for us, this is just semantics. for a "real" assembler,
@@ -62,40 +62,38 @@ function overrides.LI(self, name)
 
     if im.portion then
         -- FIXME: use appropriate instruction based on portion?
-        self:push_new('ADDIU', rt, 'R0', im)
+        self:push_new('ADDIU', dest, 'R0', im)
         return
     end
 
     im.tok = im.tok % 0x100000000
     if im.tok >= 0x10000 and im.tok <= 0xFFFF8000 then
-        local rs = rt
+        local temp = self:token(im):set('portion', 'upper')
-        local immediate = self:token(im):set('portion', 'upper')
+        self:push_new('LUI', dest, temp)
-        self:push_new('LUI', rt, immediate)
         if im.tok % 0x10000 ~= 0 then
-            local immediate = self:token(im):set('portion', 'lower')
+            local temp = self:token(im):set('portion', 'lower')
-            self:push_new('ORI', rt, rs, immediate)
+            self:push_new('ORI', dest, dest, temp)
         end
     elseif im.tok >= 0x8000 and im.tok < 0x10000 then
-        local immediate = self:token(im):set('portion', 'lower')
+        local temp = self:token(im):set('portion', 'lower')
-        self:push_new('ORI', rt, 'R0', immediate)
+        self:push_new('ORI', dest, 'R0', temp)
     else
-        local immediate = self:token(im):set('portion', 'lower')
+        local temp = self:token(im):set('portion', 'lower')
-        self:push_new('ADDIU', rt, 'R0', immediate)
+        self:push_new('ADDIU', dest, 'R0', temp)
     end
 end
 
-function overrides.LA(self, name)
+function overrides:LA(name)
-    local rt = self:pop('CPU')
+    local dest = self:pop('CPU')
     local im = self:pop('CONST')
 
-    local rs = rt
+    local im = self:token(im):set('portion', 'upperoff')
-    local immediate = self:token(im):set('portion', 'upperoff')
+    self:push_new('LUI', dest, im)
-    self:push_new('LUI', rt, immediate)
+    local im = self:token(im):set('portion', 'lower')
-    local immediate = self:token(im):set('portion', 'lower')
+    self:push_new('ADDIU', dest, dest, im)
-    self:push_new('ADDIU', rt, rt, immediate)
 end
 
-function overrides.PUSH(self, name)
+function overrides:PUSH(name)
     local w = name == 'PUSH' and 'SW' or 'LW'
     local stack = {}
     for _, t in ipairs(self.s) do
@@ -115,8 +113,8 @@ function overrides.PUSH(self, name)
         self:error(name..' requires at least one argument')
     end
     if name == 'PUSH' then
-        local immediate = self:token(#stack*4):set('negate')
+        local im = self:token(#stack*4):set('negate')
-        self:push_new('ADDIU', 'SP', 'SP', immediate)
+        self:push_new('ADDIU', 'SP', 'SP', im)
     end
     for i, r in ipairs(stack) do
         if r ~= '' then
@@ -128,65 +126,60 @@ function overrides.PUSH(self, name)
         self:push_new('JR', 'RA')
     end
     if name == 'POP' or name == 'JPOP' then
-        local immediate = #stack * 4
+        local im = #stack * 4
-        self:push_new('ADDIU', 'SP', 'SP', immediate)
+        self:push_new('ADDIU', 'SP', 'SP', im)
     end
 end
 overrides.POP = overrides.PUSH
 overrides.JPOP = overrides.PUSH
 
-function overrides.NAND(self, name)
+function overrides:NAND(name)
-    local rd = self:pop('CPU')
+    local dest = self:pop('CPU')
-    local rs = self:pop('CPU')
+    local src = self:pop('CPU')
-    local rt = self:pop('CPU')
+    local target = self:pop('CPU')
-    self:push_new('AND', rd, rs, rt)
+    self:push_new('AND', dest, src, target)
-    local rs = rd
+    self:push_new('NOR', dest, dest, 'R0') -- NOT
-    local rt = 'R0'
-    self:push_new('NOR', rd, rs, rt)
 end
 
-function overrides.NANDI(self, name)
+function overrides:NANDI(name)
-    local rt = self:pop('CPU')
+    local dest = self:pop('CPU')
-    local rs = self:pop('CPU')
+    local src = self:pop('CPU')
-    local immediate = self:pop('CONST')
+    local im = self:pop('CONST')
-    self:push_new('ANDI', rt, rs, immediate)
+    self:push_new('ANDI', dest, src, im)
-    local rd = rt
+    self:push_new('NOR', dest, dest, 'R0') -- NOT
-    local rs = rt
-    local rt = 'R0'
-    self:push_new('NOR', rd, rs, rt)
 end
 
-function overrides.NORI(self, name)
+function overrides:NORI(name)
-    local rt = self:pop('CPU')
+    local dest = self:pop('CPU')
-    local rs = self:pop('CPU')
+    local src = self:pop('CPU')
-    local immediate = self:pop('CONST')
+    local im = self:pop('CONST')
-    self:push_new('ORI', rt, rs, immediate)
+    self:push_new('ORI', dest, src, im)
-    local rd = rt
+    self:push_new('NOR', dest, dest, 'R0') -- NOT
-    local rs = rt
-    local rt = 'R0'
-    self:push_new('NOR', rd, rs, rt)
 end
 
-function overrides.ROL(self, name)
+function overrides:ROL(name)
-    -- FIXME
+    local first = name == 'ROL' and 'SLL' or 'SRL'
-    local rd, rs, rt
+    local second = name == 'ROL' and 'SRL' or 'SLL'
-    local left = self:pop('CPU')
+    local dest = self:pop('CPU')
-    rt = self:pop('CPU')
+    local src = self:pop('CPU')
-    local immediate = self:pop('CONST')
+    local im = self:pop('CONST')
-    error('Internal Error: unimplemented')
+    if dest == 'AT' or src == 'AT' then
-end
+        self:error('registers cannot be AT in this pseudo-instruction')
+    end
 
-function overrides.ROR(self, name)
+    self:push_new(first, dest, src, im)
-    -- FIXME
+    local temp, err = im:compute()
-    local right = self:pop('CPU')
+    if err then
-    local rt = self:pop('CPU')
+        self:error(err, temp)
-    local immediate = self:pop('CONST')
+    end
-    error('Internal Error: unimplemented')
+    self:push_new(second, 'AT', src, 32 - temp)
+    self:push_new('OR', dest, dest, 'AT')
 end
+overrides.ROR = overrides.ROL
 
-function overrides.JR(self, name)
+function overrides:JR(name)
-    local rs = self:peek() and self:pop('CPU') or 'RA'
+    local src = self:peek() and self:pop('CPU') or 'RA'
-    self:push_new('JR', rs)
+    self:push_new('JR', src)
 end
 
 local branch_basics = {
@@ -204,17 +197,17 @@ local branch_basics = {
     BNEIL = 'BNEL',
 }
 
-function overrides.BEQI(self, name)
+function overrides:BEQI(name)
     local branch = branch_basics[name]
     local reg = self:pop('CPU')
-    local immediate = self:pop('CONST')
+    local im = self:pop('CONST')
     local offset = self:pop('REL'):set('signed')
 
     if reg == 'AT' then
         self:error('register cannot be AT in this pseudo-instruction')
     end
 
-    self:push_new('ADDIU', 'AT', 'R0', immediate)
+    self:push_new('ADDIU', 'AT', 'R0', im)
 
     self:push_new(branch, reg, 'AT', offset)
 end
@@ -222,17 +215,17 @@ overrides.BNEI = overrides.BEQI
 overrides.BEQIL = overrides.BEQI
 overrides.BNEIL = overrides.BEQI
 
-function overrides.BLTI(self, name)
+function overrides:BLTI(name)
     local branch = branch_basics[name]
     local reg = self:pop('CPU')
-    local immediate = self:pop('CONST')
+    local im = self:pop('CONST')
     local offset = self:pop('REL'):set('signed')
 
     if reg == 'AT' then
         self:error('register cannot be AT in this pseudo-instruction')
     end
 
-    self:push_new('SLTI', 'AT', reg, immediate)
+    self:push_new('SLTI', 'AT', reg, im)
 
     self:push_new(branch, 'R0', 'AT', offset)
 end
@@ -240,29 +233,31 @@ overrides.BGEI = overrides.BLTI
 overrides.BLTIL = overrides.BLTI
 overrides.BGEIL = overrides.BLTI
 
-function overrides.BLEI(self, name)
+function overrides:BLEI(name)
     -- TODO: this can probably be optimized
+    if name:sub(#name) == 'L' then
+        self:error('unimplemented pseudo-instruction', name)
+    end
     local branch = branch_basics[name]
     local reg = self:pop('CPU')
-    local immediate = self:pop('CONST')
+    local im = self:pop('CONST')
     local offset = self:pop('REL'):set('signed')
 
     if reg == 'AT' then
         self:error('register cannot be AT in this pseudo-instruction')
     end
 
-    self:push_new('ADDIU', 'AT', 'R0', immediate)
+    self:push_new('ADDIU', 'AT', 'R0', im)
 
     local beq_offset
-    if name == 'BLEI' then
+    if name == 'BLEI' or name =='BLEIL' then
         beq_offset = offset
     else
-        -- FIXME: this probably isn't correct for branch-likely instructions
         beq_offset = 2 -- branch to delay slot of the next branch
     end
-    self:push_new('BEQ', reg, 'R0', beq_offset)
+    self:push_new('BEQ', reg, 'AT', beq_offset)
 
-    self:push_new('SLTI', 'AT', reg, immediate)
+    self:push_new('SLT', 'AT', reg, 'AT')
 
     self:push_new(branch, 'AT', 'R0', offset)
 end