Implement unconditional branching support
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@4498 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/InstSelectSimple.cpp b/lib/Target/X86/InstSelectSimple.cpp
index 144dc22..253f3dd 100644
--- a/lib/Target/X86/InstSelectSimple.cpp
+++ b/lib/Target/X86/InstSelectSimple.cpp
@@ -55,6 +55,7 @@
// fixed X86 code for each instruction.
//
void visitReturnInst(ReturnInst &RI);
+ void visitBranchInst(BranchInst &BI);
void visitAdd(BinaryOperator &B);
void visitShiftInst(ShiftInst &I);
@@ -162,6 +163,14 @@
BuildMI(BB, X86::RET, 0);
}
+void ISel::visitBranchInst(BranchInst &BI) {
+ if (BI.isConditional()) // Only handles unconditional branches so far...
+ visitInstruction(BI);
+
+ BuildMI(BB, X86::JMP, 1).addPCDisp(BI.getSuccessor(0));
+}
+
+
/// Shift instructions: 'shl', 'sar', 'shr' - Some special cases here
/// for constant immediate shift values, and for constant immediate
/// shift values equal to 1. Even the general case is sort of special,
diff --git a/lib/Target/X86/X86ISelSimple.cpp b/lib/Target/X86/X86ISelSimple.cpp
index 144dc22..253f3dd 100644
--- a/lib/Target/X86/X86ISelSimple.cpp
+++ b/lib/Target/X86/X86ISelSimple.cpp
@@ -55,6 +55,7 @@
// fixed X86 code for each instruction.
//
void visitReturnInst(ReturnInst &RI);
+ void visitBranchInst(BranchInst &BI);
void visitAdd(BinaryOperator &B);
void visitShiftInst(ShiftInst &I);
@@ -162,6 +163,14 @@
BuildMI(BB, X86::RET, 0);
}
+void ISel::visitBranchInst(BranchInst &BI) {
+ if (BI.isConditional()) // Only handles unconditional branches so far...
+ visitInstruction(BI);
+
+ BuildMI(BB, X86::JMP, 1).addPCDisp(BI.getSuccessor(0));
+}
+
+
/// Shift instructions: 'shl', 'sar', 'shr' - Some special cases here
/// for constant immediate shift values, and for constant immediate
/// shift values equal to 1. Even the general case is sort of special,
diff --git a/lib/Target/X86/X86InstrInfo.def b/lib/Target/X86/X86InstrInfo.def
index 519e768..327c4e6 100644
--- a/lib/Target/X86/X86InstrInfo.def
+++ b/lib/Target/X86/X86InstrInfo.def
@@ -33,8 +33,9 @@
// The second instruction must always be the noop instruction: (FIXME, not yet)
I(NOOP , "nop", 0, X86II::Void) // nop 90
-// Miscellaneous instructions
+// Flow control instructions
I(RET , "ret", M_RET_FLAG, X86II::Void) // ret CB
+I(JMP , "jmp", M_BRANCH_FLAG, X86II::Void) // jmp foo EB|E9 cb|w
// Move instructions
I(MOVrr8 , "movb", 0, 0) // R8 = R8 88/r