INTERMEDIATE CODE GENERATION

Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.





Addresses and Instructions
Three-address code is built from two concepts: addresses and instructions. An address can be one of the following
• A name: In an implementation, a source name is replaced by a pointer to its symbol-table entry, where all information about the name is kept.
• A constant: In practice, a compiler must deal with many different types of constants and variables.
• A compiler-generated temporary: It is useful, especially in optimizing compilers, to create a distinct name each time a temporary is needed.
We now consider the common three-address instructions and below is a list of this instructions forms:
1. Assignment instructions of the form x = y op z, where op is a binary arithmetic or logical operation, and x, y, and z are addresses.
2. Assignments of the form x = op y, where op is a unary operation.
3. Copy instructions of the form x = y, where x is assigned the value of y.
4. An unconditional jump goto L. The three-address instruction with label L is the next to be executed.
5. Conditional jumps of the form if x goto L and if False x goto L. These instructions execute the instruction with label L next if x is true and false, respectively.
6. Conditional jumps such as if x relop y goto L, which apply a relational operator (<, ==, >=, etc.) to x and y, and execute the instruction with label L next if x stands in relation relop to y. If not, the three-address instruction following i f x relop y goto L is executed next, in sequence.
7. Procedure calls and returns are implemented using the following instructions:
Func begin
Func end
Param T
…
Call P,n
Return p
Param p (place value parameter p on the stack)
Refparam p ( place refrence parameter p on the stack)
8. Indexed copy instructions of the form x = y[i] and x[i] = y. The instruction x = y[i] sets x to the value in the location i memory units beyond location y .
9. Address and pointer assignments of the form x = & y, x = * y, and * x = y. The instruction x = & y sets the r-value of x to be the location (l-value) of y.