Add branch flag on branch instructions

[lbianc]

Summary

Some branch patterns of PPC64 was missing the branch flag, impacting on LLDB execution.
The test case is the "next" command, which should stop on the next line, but without
this change, it continue executing as the "continue" command.

[nemanjai]

I think it's fine to set the flag on the asm parser defs. They certainly are branches.

lib/Target/PowerPC/PPCInstrInfo.td

1291 ↗

(On Diff #125578)

Why is this needed? This flag is set on line 1261.

4282 ↗

(On Diff #125578)

Why not just set the isBranch flag here rather than repeating it in a number of places within this scope?

[lbianc]

lib/Target/PowerPC/PPCInstrInfo.td

1291 ↗

(On Diff #125578)

Not needed here, didn't realize that parent was setting it. Will be removed.

4282 ↗

(On Diff #125578)

Ok, moving I will move it to the parent, thanks!

[lbianc]

Moving flag set to parent

Add the branch flat in the parent list, as all children need it.

[nemanjai]

LGTM.

[lbianc]

@nemanjai, I still don't have permissions for committing, so could you commit this?
Thanks!

[nemanjai]

In D40846#950789, @lbianc wrote:

@nemanjai, I still don't have permissions for committing, so could you commit this?
Thanks!

OK. I'm just in the middle of something until the end of the day. I'll commit it first thing tomorrow morning.

[lbianc]

This comment was removed by lbianc.

llvm/trunk/lib/Target/PowerPC/PPCInstrInfo.td

def RLWIMIobm : PPCAsmPseudo<"rlwimi. $rA, $rS, $n, $b",
                             (ins g8rc:$rA, g8rc:$rS, u5imm:$n, i32imm:$b)>;
 def RLWNMbm : PPCAsmPseudo<"rlwnm $rA, $rS, $n, $b",
                           (ins g8rc:$rA, g8rc:$rS, u5imm:$n, i32imm:$b)>;
 def RLWNMobm : PPCAsmPseudo<"rlwnm. $rA, $rS, $n, $b",
                            (ins g8rc:$rA, g8rc:$rS, u5imm:$n, i32imm:$b)>;
 
 // These generic branch instruction forms are used for the assembler parser only.
 // Defs and Uses are conservative, since we don't know the BO value.
-let PPC970_Unit = 7 in {
+let PPC970_Unit = 7, isBranch = 1 in {
   let Defs = [CTR], Uses = [CTR, RM] in {
     def gBC : BForm_3<16, 0, 0, (outs),
                       (ins u5imm:$bo, crbitrc:$bi, condbrtarget:$dst),
                       "bc $bo, $bi, $dst">;
     def gBCA : BForm_3<16, 1, 0, (outs),
                        (ins u5imm:$bo, crbitrc:$bi, abscondbrtarget:$dst),
                        "bca $bo, $bi, $dst">;
     let isAsmParserOnly = 1 in {