From b9e93a983209e6ea5d4ebba13c670818dfdf7e6c Mon Sep 17 00:00:00 2001
From: inglorion <voodoo@inglorion.net>
Date: Sat, 8 Jan 2011 10:59:55 +0100
Subject: [PATCH] Implemented shift actions for i386 and AMD64

---
 lib/voodoo/generators/common_code_generator.rb |  4 ++++
 lib/voodoo/generators/nasm_generator.rb        | 30 +++++++++++++++++++++-----
 2 files changed, 29 insertions(+), 5 deletions(-)

diff --git a/lib/voodoo/generators/common_code_generator.rb b/lib/voodoo/generators/common_code_generator.rb
index 65e2116..627c934 100644
--- a/lib/voodoo/generators/common_code_generator.rb
+++ b/lib/voodoo/generators/common_code_generator.rb
@@ -55,6 +55,8 @@ module Voodoo
     # of the following methods, which must be implemented by subclasses:
     #
     # - #align
+    # - #asr
+    # - #bsr
     # - #byte
     # - #call
     # - #end_if
@@ -75,6 +77,8 @@ module Voodoo
     # - #set
     # - #set_byte
     # - #set_word
+    # - #shl
+    # - #shr
     # - #string
     # - #word
     #
diff --git a/lib/voodoo/generators/nasm_generator.rb b/lib/voodoo/generators/nasm_generator.rb
index c157b56..5b45a9e 100644
--- a/lib/voodoo/generators/nasm_generator.rb
+++ b/lib/voodoo/generators/nasm_generator.rb
@@ -224,7 +224,8 @@ module Voodoo
 
     # Test if op is a binary operation
     def binop? op
-      [:div, :mod, :sub].member?(op) || symmetric_operation?(op)
+      [:asr, :bsr, :div, :mod, :shl, :shr, :sub].member?(op) ||
+        symmetric_operation?(op)
     end
 
     # Test if a value is an integer
@@ -452,14 +453,15 @@ module Voodoo
         x_ref = load_value x, @DX
         y_ref = load_value y, @BX
 
+        mnemonic = action_to_mnemonic op
         if memory_operand?(target_ref)
           if memory_operand?(x_ref) || memory_operand?(y_ref)
             emit "mov #{@CX}, #{x_ref}\n"
-            emit "#{op} #{@CX}, #{y_ref}\n"
+            emit "#{mnemonic} #{@CX}, #{y_ref}\n"
             emit "mov #{target_ref}, #{@CX}\n"
           else
             emit "mov #{@WORD_NAME} #{target_ref}, #{x_ref}\n"
-            emit "#{op} #{@WORD_NAME} #{target_ref}, #{y_ref}\n"
+            emit "#{mnemonic} #{@WORD_NAME} #{target_ref}, #{y_ref}\n"
           end
         else
           raise "Can't happen: target_ref is #{target_ref.inspect}"
@@ -477,11 +479,12 @@ module Voodoo
 
       target_ref = load_value target, @BX
       y_ref = load_value y, @DX
+      mnemonic = action_to_mnemonic op
       if memory_operand?(target_ref) && memory_operand?(y_ref)
         emit "mov #{@AX}, #{y_ref}\n"
-        emit "#{op} #{target_ref}, #{@AX}\n"
+        emit "#{mnemonic} #{target_ref}, #{@AX}\n"
       else
-        emit "#{op} #{@WORD_NAME} #{target_ref}, #{y_ref}\n"
+        emit "#{mnemonic} #{@WORD_NAME} #{target_ref}, #{y_ref}\n"
       end
     end
 
@@ -542,6 +545,7 @@ module Voodoo
 
     # Evaluate an expression.
     # The result is stored in _register_ (@RETURN_REG by default).
+    # The following registers may be clobbered: @AX, @BX, @CX, @DX
     def eval_expr words, register = @RETURN_REG
       if words.length == 1
         if words[0] == 0
@@ -552,6 +556,10 @@ module Voodoo
       else
         op = words[0]
         case op
+        when :asr, :bsr, :shl, :shr
+          load_value_into_register words[2], @CX
+          load_value_into_register words[1], register
+          emit "#{action_to_mnemonic op} #{register}, cl\n"
         when :call
           call *words[1..-1]
         when :div
@@ -698,6 +706,18 @@ module Voodoo
     # == Miscellaneous
     #
 
+    # Translates a Voodoo action name to an x86 mnemonic
+    def action_to_mnemonic action
+      case action
+      when :asr
+        :sar
+      when :bsr
+        :shr
+      else
+        action
+      end
+    end
+
     # Emit a comment
     def comment text
       emit ";#{text}\n"
-- 
2.11.4.GIT