Index: llvm/trunk/lib/Target/X86/X86FlagsCopyLowering.cpp =================================================================== --- llvm/trunk/lib/Target/X86/X86FlagsCopyLowering.cpp +++ llvm/trunk/lib/Target/X86/X86FlagsCopyLowering.cpp @@ -555,7 +555,7 @@ // If the flags were killed, we're done with this block. if (FlagsKilled) - break; + continue; // Otherwise we need to scan successors for ones where the flags live-in // and queue those up for processing. Index: llvm/trunk/test/CodeGen/X86/flags-copy-lowering.mir =================================================================== --- llvm/trunk/test/CodeGen/X86/flags-copy-lowering.mir +++ llvm/trunk/test/CodeGen/X86/flags-copy-lowering.mir @@ -72,6 +72,12 @@ call void @foo() ret void } + + define i64 @test_branch_with_livein_and_kill(i64 %a, i64 %b) { + entry: + call void @foo() + ret i64 0 + } ... --- name: test_branch @@ -553,3 +559,76 @@ RET 0 ... +--- +name: test_branch_with_livein_and_kill +# CHECK-LABEL: name: test_branch_with_livein_and_kill +liveins: + - { reg: '$rdi', virtual-reg: '%0' } + - { reg: '$rsi', virtual-reg: '%1' } +body: | + bb.0: + successors: %bb.1, %bb.2, %bb.3 + liveins: $rdi, $rsi + + %0:gr64 = COPY $rdi + %1:gr64 = COPY $rsi + CMP64rr %0, %1, implicit-def $eflags + %2:gr64 = COPY $eflags + ; CHECK-NOT: COPY{{( killed)?}} $eflags + ; CHECK: %[[S_REG:[^:]*]]:gr8 = SETSr implicit $eflags + ; CHECK-NEXT: %[[NE_REG:[^:]*]]:gr8 = SETNEr implicit $eflags + ; CHECK-NEXT: %[[A_REG:[^:]*]]:gr8 = SETAr implicit $eflags + ; CHECK-NEXT: %[[B_REG:[^:]*]]:gr8 = SETBr implicit $eflags + ; CHECK-NOT: COPY{{( killed)?}} $eflags + + ADJCALLSTACKDOWN64 0, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp + CALL64pcrel32 @foo, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax + ADJCALLSTACKUP64 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp + + $eflags = COPY %2 + JA_1 %bb.1, implicit $eflags + JB_1 %bb.2, implicit $eflags + JMP_1 %bb.3 + ; CHECK-NOT: $eflags = + ; + ; CHECK: TEST8rr %[[A_REG]], %[[A_REG]], implicit-def $eflags + ; CHECK-NEXT: JNE_1 %bb.1, implicit killed $eflags + ; CHECK-SAME: {{$[[:space:]]}} + ; CHECK-NEXT: bb.4: + ; CHECK-NEXT: successors: {{.*$}} + ; CHECK-SAME: {{$[[:space:]]}} + ; CHECK-NEXT: TEST8rr %[[B_REG]], %[[B_REG]], implicit-def $eflags + ; CHECK-NEXT: JNE_1 %bb.2, implicit killed $eflags + ; CHECK-NEXT: JMP_1 %bb.3 + + bb.1: + liveins: $eflags + + %3:gr64 = CMOVE64rr %0, %1, implicit killed $eflags + ; CHECK-NOT: $eflags = + ; CHECK: TEST8rr %[[NE_REG]], %[[NE_REG]], implicit-def $eflags + ; CHECK-NEXT: %3:gr64 = CMOVE64rr %0, %1, implicit killed $eflags + $rax = COPY %3 + RET 0, $rax + + bb.2: + liveins: $eflags + + %4:gr64 = CMOVNE64rr %0, %1, implicit killed $eflags + ; CHECK-NOT: $eflags = + ; CHECK: TEST8rr %[[NE_REG]], %[[NE_REG]], implicit-def $eflags + ; CHECK-NEXT: %4:gr64 = CMOVNE64rr %0, %1, implicit killed $eflags + $rax = COPY %4 + RET 0, $rax + + bb.3: + liveins: $eflags + + %5:gr64 = CMOVS64rr %0, %1, implicit killed $eflags + ; CHECK-NOT: $eflags = + ; CHECK: TEST8rr %[[S_REG]], %[[S_REG]], implicit-def $eflags + ; CHECK-NEXT: %5:gr64 = CMOVNE64rr %0, %1, implicit killed $eflags + $rax = COPY %5 + RET 0, $rax + +...