[Docs][CodeGenerator] Don't specify the number of operands in BuildMI
Patch by Visoiu Mistrih Francis.
Differential Revision: http://reviews.llvm.org/D21819
llvm-svn: 274128
diff --git a/llvm/docs/CodeGenerator.rst b/llvm/docs/CodeGenerator.rst
index fc537a7..6a54343 100644
--- a/llvm/docs/CodeGenerator.rst
+++ b/llvm/docs/CodeGenerator.rst
@@ -386,32 +386,27 @@
.. code-block:: c++
// Create a 'DestReg = mov 42' (rendered in X86 assembly as 'mov DestReg, 42')
- // instruction. The '1' specifies how many operands will be added.
- MachineInstr *MI = BuildMI(X86::MOV32ri, 1, DestReg).addImm(42);
-
- // Create the same instr, but insert it at the end of a basic block.
+ // instruction and insert it at the end of the given MachineBasicBlock.
+ const TargetInstrInfo &TII = ...
MachineBasicBlock &MBB = ...
- BuildMI(MBB, X86::MOV32ri, 1, DestReg).addImm(42);
+ DebugLoc DL;
+ MachineInstr *MI = BuildMI(MBB, DL, TII.get(X86::MOV32ri), DestReg).addImm(42);
// Create the same instr, but insert it before a specified iterator point.
MachineBasicBlock::iterator MBBI = ...
- BuildMI(MBB, MBBI, X86::MOV32ri, 1, DestReg).addImm(42);
+ BuildMI(MBB, MBBI, DL, TII.get(X86::MOV32ri), DestReg).addImm(42);
// Create a 'cmp Reg, 0' instruction, no destination reg.
- MI = BuildMI(X86::CMP32ri, 2).addReg(Reg).addImm(0);
+ MI = BuildMI(MBB, DL, TII.get(X86::CMP32ri8)).addReg(Reg).addImm(42);
// Create an 'sahf' instruction which takes no operands and stores nothing.
- MI = BuildMI(X86::SAHF, 0);
+ MI = BuildMI(MBB, DL, TII.get(X86::SAHF));
// Create a self looping branch instruction.
- BuildMI(MBB, X86::JNE, 1).addMBB(&MBB);
+ BuildMI(MBB, DL, TII.get(X86::JNE)).addMBB(&MBB);
-The key thing to remember with the ``BuildMI`` functions is that you have to
-specify the number of operands that the machine instruction will take. This
-allows for efficient memory allocation. You also need to specify if operands
-default to be uses of values, not definitions. If you need to add a definition
-operand (other than the optional destination register), you must explicitly mark
-it as such:
+If you need to add a definition operand (other than the optional destination
+register), you must explicitly mark it as such:
.. code-block:: c++