#include "AArch64Subtarget.h"
#include "AArch64TargetMachine.h"
#include "MCTargetDesc/AArch64AddressingModes.h"
+#include "llvm/Analysis/BranchProbabilityInfo.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/FastISel.h"
#include "llvm/CodeGen/FunctionLoweringInfo.h"
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(AArch64::Bcc))
.addImm(CC)
.addMBB(TBB);
- FuncInfo.MBB->addSuccessor(TBB);
+
+ // Obtain the branch weight and add the TrueBB to the successor list.
+ uint32_t BranchWeight = 0;
+ if (FuncInfo.BPI)
+ BranchWeight = FuncInfo.BPI->getEdgeWeight(BI->getParent(),
+ TBB->getBasicBlock());
+ FuncInfo.MBB->addSuccessor(TBB, BranchWeight);
FastEmitBranch(FBB, DbgLoc);
return true;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(AArch64::Bcc))
.addImm(CC)
.addMBB(TBB);
- FuncInfo.MBB->addSuccessor(TBB);
+
+ // Obtain the branch weight and add the TrueBB to the successor list.
+ uint32_t BranchWeight = 0;
+ if (FuncInfo.BPI)
+ BranchWeight = FuncInfo.BPI->getEdgeWeight(BI->getParent(),
+ TBB->getBasicBlock());
+ FuncInfo.MBB->addSuccessor(TBB, BranchWeight);
+
FastEmitBranch(FBB, DbgLoc);
return true;
}
MachineBasicBlock *Target = (Imm == 0) ? FBB : TBB;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(AArch64::B))
.addMBB(Target);
- FuncInfo.MBB->addSuccessor(Target);
+
+ // Obtain the branch weight and add the target to the successor list.
+ uint32_t BranchWeight = 0;
+ if (FuncInfo.BPI)
+ BranchWeight = FuncInfo.BPI->getEdgeWeight(BI->getParent(),
+ Target->getBasicBlock());
+ FuncInfo.MBB->addSuccessor(Target, BranchWeight);
return true;
} else if (foldXALUIntrinsic(CC, I, BI->getCondition())) {
// Fake request the condition, otherwise the intrinsic might be completely
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(AArch64::Bcc))
.addImm(CC)
.addMBB(TBB);
- FuncInfo.MBB->addSuccessor(TBB);
+
+ // Obtain the branch weight and add the TrueBB to the successor list.
+ uint32_t BranchWeight = 0;
+ if (FuncInfo.BPI)
+ BranchWeight = FuncInfo.BPI->getEdgeWeight(BI->getParent(),
+ TBB->getBasicBlock());
+ FuncInfo.MBB->addSuccessor(TBB, BranchWeight);
FastEmitBranch(FBB, DbgLoc);
return true;
BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(AArch64::Bcc))
.addImm(CC)
.addMBB(TBB);
- FuncInfo.MBB->addSuccessor(TBB);
+
+ // Obtain the branch weight and add the TrueBB to the successor list.
+ uint32_t BranchWeight = 0;
+ if (FuncInfo.BPI)
+ BranchWeight = FuncInfo.BPI->getEdgeWeight(BI->getParent(),
+ TBB->getBasicBlock());
+ FuncInfo.MBB->addSuccessor(TBB, BranchWeight);
+
FastEmitBranch(FBB, DbgLoc);
return true;
}
--- /dev/null
+; RUN: llc -mtriple=arm64-apple-darwin -aarch64-atomic-cfg-tidy=0 < %s | FileCheck %s
+; RUN: llc -mtriple=arm64-apple-darwin -aarch64-atomic-cfg-tidy=0 -fast-isel -fast-isel-abort < %s | FileCheck %s
+
+; Test if the BBs are reordred according to their branch weights.
+define i64 @branch_weights_test(i64 %a, i64 %b) {
+; CHECK-LABEL: branch_weights_test
+; CHECK-LABEL: success
+; CHECK-LABEL: fail
+ %1 = icmp ult i64 %a, %b
+ br i1 %1, label %fail, label %success, !prof !0
+
+fail:
+ ret i64 -1
+
+success:
+ ret i64 0
+}
+
+!0 = metadata !{metadata !"branch_weights", i32 0, i32 2147483647}