[llvm-commits] CVS: llvm-gcc/gcc/llvm-representation.h llvm-representation.c

[Chris Lattner]

Changes in directory llvm-gcc/gcc:

llvm-representation.h updated: 1.5 -> 1.6
llvm-representation.c updated: 1.6 -> 1.7

---
Log message:

Improve compile times with llvm-gcc by folding conditional branches into 
unconditional branches when the condition is obviously a constant.


---
Diffs of the changes:  (+12 -1)

Index: llvm-gcc/gcc/llvm-representation.h
diff -u llvm-gcc/gcc/llvm-representation.h:1.5 llvm-gcc/gcc/llvm-representation.h:1.6
--- llvm-gcc/gcc/llvm-representation.h:1.5	Fri May  7 11:22:58 2004
+++ llvm-gcc/gcc/llvm-representation.h	Fri May  7 11:55:49 2004
@@ -200,6 +200,11 @@
 llvm_instruction *create_binary_inst(const char *Name, enum InstOpcode Opc,
                                      llvm_value *Op1, llvm_value *Op2);
 llvm_instruction *create_uncond_branch(struct llvm_basicblock *Dest);
+
+/* create_cond_branch - Create a conditional branch on Val to the two blocks.
+ * Be aware that if Val is a constant, this will actually return an
+ * unconditional branch.
+ */
 llvm_instruction *create_cond_branch(llvm_value *Val,
                                      struct llvm_basicblock *TrueBlock,
                                      struct llvm_basicblock *FalseBlock);


Index: llvm-gcc/gcc/llvm-representation.c
diff -u llvm-gcc/gcc/llvm-representation.c:1.6 llvm-gcc/gcc/llvm-representation.c:1.7
--- llvm-gcc/gcc/llvm-representation.c:1.6	Fri May  7 11:22:57 2004
+++ llvm-gcc/gcc/llvm-representation.c	Fri May  7 11:55:49 2004
@@ -572,7 +572,13 @@
 llvm_instruction *create_cond_branch(llvm_value *Cond,
                                      llvm_basicblock *TrueBlock,
                                      llvm_basicblock *FalseBlock) {
-  llvm_instruction *New = llvm_instruction_new(VoidTy, "", O_Br, 3);
+  llvm_instruction *New;
+  if (Cond == llvm_constant_bool_true)
+    return create_uncond_branch(TrueBlock);
+  else if (Cond == llvm_constant_bool_false)
+    return create_uncond_branch(FalseBlock);
+
+  New = llvm_instruction_new(VoidTy, "", O_Br, 3);
   New->Operands[0] = Cond;
   New->Operands[1] = D2V(TrueBlock);
   New->Operands[2] = D2V(FalseBlock);