报告 1.0

phase4/README.md

@@ -6,11 +6,47 @@
 
 **12111611 Ruixiang Jiang**
 
-
+## How to Run and Test
+1. make splc: `make`
+2. auto test: `make test`
 
 ## Design
-
+### Language
+Use python to implement make splc with pyinstaller
 ### Procedure Call
+before the function is called:
+1. Store Active Variables in the stack
+2. jal in the target function
+3. Store ra in the stack
+
+after the function is called:
+1. get ra in the stack
+2. the result is stored in the stack 
+3. the Active Variables are restored from the stack
+
+### Translation processing
+check if the three address code has numbers:
+1. Support the return value and input as numbers
+2. Support multiplication and division containing numbers
+3. The positions of registers and numbers can be switched arbitrarily (x := y - #k or x := #y - k is OK)
+
+More efficient: 
+
+1. If there are no unknowns in addition, subtraction, multiplication, and division (that is, all numbers), the result is directly assigned to the target register
+2. For commands that use a stack Variable, the variable in the stack is moved to the register using `lw`. Similarly, the variable in the stack can be identified by `sw` to the corresponding position
+
+More secure:
+
+In mips, an addi number greater than 32767 or less than -32767 causes an arithmetic overflow, which we detected and addressed (see test15).
+
+Easier to read:
+
+At the beginning, jal directly jumps to main, obtains the return value of main function and then ends, without adjusting the position of the three-address code function
+
+### Variables
+We use specific registers `s6` for reading and writing and a portion of the stack space for storing common variables
+
+Have tried it on multiple platforms, websites, and can run on Mars and various versions of spim
 
 #### Active Variables
 
@@ -32,3 +68,5 @@ Finally, clear the set after getting a new function TAC `FUNCTION f :`
 
 
 
+
+