[SubZero] Branch optimization

tests_lit/llvm2ice_tests/branch-opt.ll

 ; Tests the branch optimizations under O2 (against a lack of
 ; optimizations under Om1).
 
 ; RUN: %if --need=target_X8632 --command %p2i --filetype=obj --disassemble \
 ; RUN:   --target x8632 -i %s --args -O2 -allow-externally-defined-symbols \
 ; RUN:   | %if --need=target_X8632 --command FileCheck --check-prefix=O2 %s
 
 ; RUN: %if --need=target_X8632 --command %p2i --filetype=obj --disassemble \
 ; RUN:   --target x8632 -i %s --args -Om1 -allow-externally-defined-symbols \
 ; RUN:   | %if --need=target_X8632 --command FileCheck --check-prefix=OM1 %s
 
 ; TODO(jvoung): Stop skipping unimplemented parts (via --skip-unimplemented)
 ; once enough infrastructure is in. Also, switch to --filetype=obj
 ; when possible.
 ; RUN: %if --need=target_ARM32 --need=allow_dump \
 ; RUN:   --command %p2i --filetype=asm --assemble \
 ; RUN:   --disassemble --target arm32 -i %s --args -O2 \
 ; RUN:   -allow-externally-defined-symbols \
 ; RUN:   | %if --need=target_ARM32 --need=allow_dump \
 ; RUN:   --command FileCheck --check-prefix ARM32O2 %s
 
 ; RUN: %if --need=target_ARM32 --need=allow_dump \
 ; RUN:   --command %p2i --filetype=asm --assemble \
 ; RUN:   --disassemble --target arm32 -i %s --args -Om1 \
 ; RUN:   -allow-externally-defined-symbols \
 ; RUN:   | %if --need=target_ARM32 --need=allow_dump \
 ; RUN:   --command FileCheck \
 ; RUN:   --check-prefix ARM32OM1 %s
 
+; TODO(jaydeep.patil): Using --skip-unimplemented for MIPS32
+; RUN: %if --need=target_MIPS32 --need=allow_dump \
+; RUN:   --command %p2i --filetype=asm --assemble \
+; RUN:   --disassemble --target mips32 -i %s --args -O2 \
+; RUN:   --skip-unimplemented \
+; RUN:   -allow-externally-defined-symbols \
+; RUN:   | %if --need=target_MIPS32 --need=allow_dump \
+; RUN:   --command FileCheck --check-prefix MIPS32O2 %s
+
+; RUN: %if --need=target_MIPS32 --need=allow_dump \
+; RUN:   --command %p2i --filetype=asm --assemble \
+; RUN:   --disassemble --target mips32 -i %s --args -Om1 \
+; RUN:   --skip-unimplemented \
+; RUN:   -allow-externally-defined-symbols \
+; RUN:   | %if --need=target_MIPS32 --need=allow_dump \
+; RUN:   --command FileCheck \
+; RUN:   --check-prefix MIPS32OM1 %s
+
 declare void @dummy()
 
 ; An unconditional branch to the next block should be removed.
 define internal void @testUncondToNextBlock() {
 entry:
   call void @dummy()
   br label %next
 next:
   call void @dummy()
   ret void
@@ skipping 12 matching lines @@
 
 ; ARM32O2-LABEL: testUncondToNextBlock
 ; ARM32O2: bl {{.*}} dummy
 ; ARM32O2-NEXT: bl {{.*}} dummy
 
 ; ARM32OM1-LABEL: testUncondToNextBlock
 ; ARM32OM1: bl {{.*}} dummy
 ; ARM32OM1-NEXT: b
 ; ARM32OM1-NEXT: bl {{.*}} dummy
 
+; MIPS32O2-LABEL: testUncondToNextBlock
+; MIPS32O2: jal {{.*}} dummy
+; MIPS32O2-NEXT: nop
+; MIPS32O2-LABEL: <.LtestUncondToNextBlock$next>:
+; MIPS32O2-NEXT: jal {{.*}} dummy
+; MIPS32O2-NEXT: nop
+
+; MIPS32OM1-LABEL: testUncondToNextBlock
+; MIPS32OM1: jal {{.*}} dummy
+; MIPS32OM1-NEXT: nop
+; MIPS32OM1-NEXT: b {{.*}} <.LtestUncondToNextBlock$next>
+; MIPS32OM1-NEXT: nop
+; MIPS32OM1-LABEL: <.LtestUncondToNextBlock$next>:
+; MIPS32OM1-NEXT: jal {{.*}} dummy
+; MIPS32OM1-NEXT: nop
+
 ; For a conditional branch with a fallthrough to the next block, the
 ; fallthrough branch should be removed.
 define internal void @testCondFallthroughToNextBlock(i32 %arg) {
 entry:
   %cmp = icmp sge i32 %arg, 123
   br i1 %cmp, label %target, label %fallthrough
 fallthrough:
   call void @dummy()
   ret void
 target:
@@ skipping 33 matching lines @@
 ; ARM32OM1: cmp {{.*}}, #123
 ; ARM32OM1: movge {{.*}}, #1
 ; ARM32OM1: tst {{.*}}, #1
 ; ARM32OM1: bne
 ; ARM32OM1: b
 ; ARM32OM1: bl
 ; ARM32OM1: bx lr
 ; ARM32OM1: bl
 ; ARM32OM1: bx lr
 
+; MIPS32O2-LABEL: testCondFallthroughToNextBlock
+; MIPS32O2: li {{.*}},123
+; MIPS32O2: slt {{.*}},{{.*}},{{.*}}
+; MIPS32O2: beqz
+; MIPS32O2: nop
+; MIPS32O2: .LtestCondFallthroughToNextBlock$fallthrough
+; MIPS32O2: jal {{.*}} dummy
+; MIPS32O2: nop
+; MIPS32O2: jr
+; MIPS32O2: nop
+; MIPS32O2: .LtestCondFallthroughToNextBlock$target
+; MIPS32O2: jal {{.*}} dummy
+; MIPS32O2: nop
+; MIPS32O2: jr
+; MIPS32O2: nop
+
+; MIPS32OM1-LABEL: testCondFallthroughToNextBlock
+; MIPS32OM1: li {{.*}},123
+; MIPS32OM1: slt {{.*}},{{.*}},{{.*}}
+; MIPS32OM1: xori {{.*}},{{.*}},{{.*}}
+; MIPS32OM1: beqz
+; MIPS32OM1: nop
+; MIPS32OM1: b
+; MIPS32OM1: nop
+; MIPS32OM1: .LtestCondFallthroughToNextBlock$fallthrough
+; MIPS32OM1: jal {{.*}} dummy
+; MIPS32OM1: nop
+; MIPS32OM1: jr
+; MIPS32OM1: nop
+; MIPS32OM1: .LtestCondFallthroughToNextBlock$target
+; MIPS32OM1: jal {{.*}} dummy
+; MIPS32OM1: nop
+; MIPS32OM1: jr
+; MIPS32OM1: nop
+
 ; For a conditional branch with the next block as the target and a
 ; different block as the fallthrough, the branch condition should be
 ; inverted, the fallthrough block changed to the target, and the
 ; branch to the next block removed.
 define internal void @testCondTargetNextBlock(i32 %arg) {
 entry:
   %cmp = icmp sge i32 %arg, 123
   br i1 %cmp, label %fallthrough, label %target
 fallthrough:
   call void @dummy()
@@ skipping 36 matching lines @@
 ; ARM32OM1: cmp {{.*}}, #123
 ; ARM32OM1: movge {{.*}}, #1
 ; ARM32OM1: tst {{.*}}, #1
 ; ARM32OM1: bne
 ; ARM32OM1: b
 ; ARM32OM1: bl
 ; ARM32OM1: bx lr
 ; ARM32OM1: bl
 ; ARM32OM1: bx lr
 
+; MIPS32O2-LABEL: testCondTargetNextBlock
+; MIPS32O2: li {{.*}},123
+; MIPS32O2: slt {{.*}},{{.*}},{{.*}}
+; MIPS32O2: bnez
+; MIPS32O2: nop
+; MIPS32O2: .LtestCondTargetNextBlock$fallthrough
+; MIPS32O2: jal {{.*}} dummy
+; MIPS32O2: nop
+; MIPS32O2: jr
+; MIPS32O2: nop
+; MIPS32O2: .LtestCondTargetNextBlock$target
+; MIPS32O2: jal {{.*}} dummy
+; MIPS32O2: nop
+; MIPS32O2: jr
+; MIPS32O2: nop
+
+; MIPS32OM1-LABEL: testCondTargetNextBlock
+; MIPS32OM1: li {{.*}},123
+; MIPS32OM1: slt {{.*}},{{.*}},{{.*}}
+; MIPS32OM1: xori {{.*}},{{.*}},{{.*}}
+; MIPS32OM1: beqz
+; MIPS32OM1: nop
+; MIPS32OM1: b
+; MIPS32OM1: nop
+; MIPS32OM1: .LtestCondTargetNextBlock$fallthrough
+; MIPS32OM1: jal {{.*}} dummy
+; MIPS32OM1: nop
+; MIPS32OM1: jr
+; MIPS32OM1: nop
+; MIPS32OM1: .LtestCondTargetNextBlock$target
+; MIPS32OM1: jal {{.*}} dummy
+; MIPS32OM1: nop
+; MIPS32OM1: jr
+; MIPS32OM1: nop
+
 ; Unconditional branches to the block after a contracted block should be
 ; removed.
 define internal void @testUncondToBlockAfterContract() {
 entry:
   call void @dummy()
   br label %target
 contract:
   br label %target
 target:
   call void @dummy()
@@ skipping 13 matching lines @@
 ; OM1: call
 
 ; ARM32O2-LABEL: testUncondToBlockAfterContract
 ; ARM32O2: bl {{.*}} dummy
 ; ARM32O2-NEXT: bl {{.*}} dummy
 
 ; ARM32OM1-LABEL: testUncondToBlockAfterContract
 ; ARM32OM1: bl {{.*}} dummy
 ; ARM32OM1-NEXT: b
 ; ARM32OM1-NEXT: bl {{.*}} dummy
+
+; MIPS32O2-LABEL: testUncondToBlockAfterContract
+; MIPS32O2: jal {{.*}} dummy
+; MIPS32O2: .LtestUncondToBlockAfterContract$target
+
+; MIPS32OM1-LABEL: testUncondToBlockAfterContract
+; MIPS32OM1: jal {{.*}} dummy
+; MIPS32OM1: b
+; MIPS32OM1: .LtestUncondToBlockAfterContract$target