In particular, this preserves the kill flag, which allows the Thumb2 cbn?z
optimization to be applied in cases where a branch has been re-created after
the live variables analysis pass, e.g. by the machine block placement pass.
This appears to be low risk; a number of other targets seem to already be
doing something similar, e.g. AArch64, PowerPC.
Differential Revision: http://reviews.llvm.org/D9184
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235639
91177308-0d34-0410-b5e6-
96231b3b80d8
assert((Cond.size() == 2 || Cond.size() == 0) &&
"ARM branch conditions have two components!");
assert((Cond.size() == 2 || Cond.size() == 0) &&
"ARM branch conditions have two components!");
+ // For conditional branches, we use addOperand to preserve CPSR flags.
+
if (!FBB) {
if (Cond.empty()) { // Unconditional branch?
if (isThumb)
if (!FBB) {
if (Cond.empty()) { // Unconditional branch?
if (isThumb)
BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB);
} else
BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
BuildMI(&MBB, DL, get(BOpc)).addMBB(TBB);
} else
BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
- .addImm(Cond[0].getImm()).addReg(Cond[1].getReg());
+ .addImm(Cond[0].getImm()).addOperand(Cond[1]);
return 1;
}
// Two-way conditional branch.
BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
return 1;
}
// Two-way conditional branch.
BuildMI(&MBB, DL, get(BccOpc)).addMBB(TBB)
- .addImm(Cond[0].getImm()).addReg(Cond[1].getReg());
+ .addImm(Cond[0].getImm()).addOperand(Cond[1]);
if (isThumb)
BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0);
else
if (isThumb)
BuildMI(&MBB, DL, get(BOpc)).addMBB(FBB).addImm(ARMCC::AL).addReg(0);
else
; CHECK: str r0, [sp, [[OFFSET:#[0-9]+]]]
; CHECK: ldr [[R0:r[0-9]+]], [sp, [[OFFSET]]]
; CHECK: {{.*}}@ %do.body.i.i.i
; CHECK: str r0, [sp, [[OFFSET:#[0-9]+]]]
; CHECK: ldr [[R0:r[0-9]+]], [sp, [[OFFSET]]]
; CHECK: {{.*}}@ %do.body.i.i.i
%"class.std::__1::basic_string" = type { %"class.std::__1::__compressed_pair" }
%"class.std::__1::__compressed_pair" = type { %"class.std::__1::__libcpp_compressed_pair_imp" }
%"class.std::__1::basic_string" = type { %"class.std::__1::__compressed_pair" }
%"class.std::__1::__compressed_pair" = type { %"class.std::__1::__libcpp_compressed_pair_imp" }
; CHECK: it ne
; CHECK-NEXT: cmpne
; CHECK-NEXT: bne [[JUMPTARGET:.LBB[0-9]+_[0-9]+]]
; CHECK: it ne
; CHECK-NEXT: cmpne
; CHECK-NEXT: bne [[JUMPTARGET:.LBB[0-9]+_[0-9]+]]
-; CHECK: cmp
-; CHECK-NEXT: beq
; CHECK-NEXT: %if.else163
; CHECK-NEXT: mov.w
; CHECK-NEXT: b
; CHECK-NEXT: %if.else163
; CHECK-NEXT: mov.w
; CHECK-NEXT: b