Enable post regalloc machine licm by default.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101023 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 141 insertions, 5 deletions

diff --git a/lib/CodeGen/LLVMTargetMachine.cpp b/lib/CodeGen/LLVMTargetMachine.cpp
index ced6664..a62f0f6 100644
--- a/lib/CodeGen/LLVMTargetMachine.cpp
+++ b/lib/CodeGen/LLVMTargetMachine.cpp
@@ -66,9 +66,6 @@ static cl::opt<bool> VerifyMachineCode("verify-machineinstrs", cl::Hidden,
     cl::desc("Verify generated machine code"),
     cl::init(getenv("LLVM_VERIFY_MACHINEINSTRS")!=NULL));
 
-static cl::opt<bool> PostRAMachineLICM("postra-machine-licm", cl::Hidden,
-    cl::desc("Enable post-regalloc Machine LICM"));
-
 static cl::opt<cl::boolOrDefault>
 AsmVerbose("asm-verbose", cl::desc("Add comments to directives."),
            cl::init(cl::BOU_UNSET));
@@ -348,8 +345,7 @@ bool LLVMTargetMachine::addCommonCodeGenPasses(PassManagerBase &PM,
     printAndVerify(PM, "After StackSlotColoring");
 
     // Run post-ra machine LICM to hoist reloads / remats.
-    if (PostRAMachineLICM)
-      PM.add(createMachineLICMPass(false));
+    PM.add(createMachineLICMPass(false));
   }
 
   // Run post-ra passes.
diff --git a/test/CodeGen/X86/postra-licm.ll b/test/CodeGen/X86/postra-licm.ll
new file mode 100644
index 0000000..1c04155
--- /dev/null
+++ b/test/CodeGen/X86/postra-licm.ll
@@ -0,0 +1,140 @@
+; RUN: llc < %s -mtriple=i386-apple-darwin -relocation-model=pic -disable-fp-elim | FileCheck %s
+
+; MachineLICM should be able to hoist loop invariant reload out of the loop.
+; rdar://7233099
+
+%struct.FILE = type { i8*, i32, i32, i16, i16, %struct.__sbuf, i32, i8*, i32 (i8*)*, i32 (i8*, i8*, i32)*, i64 (i8*, i64, i32)*, i32 (i8*, i8*, i32)*, %struct.__sbuf, %struct.__sFILEX*, i32, [3 x i8], [1 x i8], %struct.__sbuf, i32, i64 }
+%struct.__sFILEX = type opaque
+%struct.__sbuf = type { i8*, i32 }
+%struct.epoch_t = type { %struct.trans_t*, %struct.trans_t*, i32, i32, i32, i32, i32 }
+%struct.trans_t = type { i32, i32, i32, i8* }
+
+@.str12 = external constant [2 x i8], align 1     ; <[2 x i8]*> [#uses=1]
+@.str19 = external constant [7 x i8], align 1     ; <[7 x i8]*> [#uses=1]
+@.str24 = external constant [4 x i8], align 1     ; <[4 x i8]*> [#uses=1]
+
+define i32 @main(i32 %c, i8** nocapture %v) nounwind ssp {
+; CHECK: main:
+entry:
+  br i1 undef, label %bb, label %bb3
+
+bb:                                               ; preds = %entry
+  unreachable
+
+bb3:                                              ; preds = %entry
+  br i1 undef, label %bb.i, label %bb.nph41
+
+bb.i:                                             ; preds = %bb3
+  unreachable
+
+bb.nph41:                                         ; preds = %bb3
+  %0 = call %struct.FILE* @"\01_fopen$UNIX2003"(i8* undef, i8* getelementptr inbounds ([2 x i8]* @.str12, i32 0, i32 0)) nounwind ; <%struct.FILE*> [#uses=3]
+  br i1 undef, label %bb4, label %bb5.preheader
+
+bb5.preheader:                                    ; preds = %bb.nph41
+  br label %bb5
+
+bb4:                                              ; preds = %bb.nph41
+  unreachable
+
+bb5:                                              ; preds = %bb5, %bb5.preheader
+  br i1 undef, label %bb7, label %bb5
+
+bb7:                                              ; preds = %bb5
+  br i1 undef, label %bb9, label %bb12
+
+bb9:                                              ; preds = %bb7
+  unreachable
+
+bb12:                                             ; preds = %bb7
+  br i1 undef, label %bb16, label %bb22
+
+bb16:                                             ; preds = %bb12
+  unreachable
+
+bb22:                                             ; preds = %bb12
+  br label %bb.i1
+
+bb.i1:                                            ; preds = %bb.i1, %bb22
+  %1 = icmp eq i8 undef, 69                       ; <i1> [#uses=1]
+  br i1 %1, label %imix_test.exit, label %bb.i1
+
+imix_test.exit:                                   ; preds = %bb.i1
+  br i1 undef, label %bb23, label %bb26.preheader
+
+bb26.preheader:                                   ; preds = %imix_test.exit
+  br i1 undef, label %bb28, label %bb30
+
+bb23:                                             ; preds = %imix_test.exit
+  unreachable
+; CHECK: %bb26.preheader.bb28_crit_edge
+; CHECK: movl -16(%ebp),
+; CHECK-NEXT: .align 4
+; CHECK-NEXT: %bb28
+
+bb28:                                             ; preds = %bb28, %bb26.preheader
+  %counter.035 = phi i32 [ %3, %bb28 ], [ 0, %bb26.preheader ] ; <i32> [#uses=2]
+  %tmp56 = shl i32 %counter.035, 2                ; <i32> [#uses=0]
+  %2 = call i8* @fgets(i8* undef, i32 50, %struct.FILE* %0) nounwind ; <i8*> [#uses=0]
+  %3 = add nsw i32 %counter.035, 1                ; <i32> [#uses=1]
+  %4 = call i32 @feof(%struct.FILE* %0) nounwind  ; <i32> [#uses=0]
+  br label %bb28
+
+bb30:                                             ; preds = %bb26.preheader
+  %5 = call i32 @strcmp(i8* undef, i8* getelementptr inbounds ([7 x i8]* @.str19, i32 0, i32 0)) nounwind readonly ; <i32> [#uses=0]
+  br i1 undef, label %bb34, label %bb70
+
+bb32.loopexit:                                    ; preds = %bb45
+  %6 = icmp eq i32 undef, 0                       ; <i1> [#uses=1]
+  %indvar.next55 = add i32 %indvar54, 1           ; <i32> [#uses=1]
+  br i1 %6, label %bb34, label %bb70
+
+bb34:                                             ; preds = %bb32.loopexit, %bb30
+  %indvar54 = phi i32 [ %indvar.next55, %bb32.loopexit ], [ 0, %bb30 ] ; <i32> [#uses=3]
+  br i1 false, label %bb35, label %bb39.preheader
+
+bb35:                                             ; preds = %bb34
+  unreachable
+
+bb39.preheader:                                   ; preds = %bb34
+  %7 = getelementptr inbounds %struct.epoch_t* undef, i32 %indvar54, i32 3 ; <i32*> [#uses=1]
+  %8 = getelementptr inbounds %struct.epoch_t* undef, i32 %indvar54, i32 2 ; <i32*> [#uses=0]
+  br i1 false, label %bb42, label %bb45
+
+bb42:                                             ; preds = %bb39.preheader
+  unreachable
+
+bb45:                                             ; preds = %bb39.preheader
+  %9 = call i32 @strcmp(i8* undef, i8* getelementptr inbounds ([4 x i8]* @.str24, i32 0, i32 0)) nounwind readonly ; <i32> [#uses=0]
+  br i1 false, label %bb47, label %bb32.loopexit
+
+bb47:                                             ; preds = %bb45
+  %10 = load i32* %7, align 4                     ; <i32> [#uses=0]
+  unreachable
+
+bb70:                                             ; preds = %bb32.loopexit, %bb30
+  br i1 undef, label %bb78, label %bb76
+
+bb76:                                             ; preds = %bb70
+  unreachable
+
+bb78:                                             ; preds = %bb70
+  br i1 undef, label %bb83, label %bb79
+
+bb79:                                             ; preds = %bb78
+  unreachable
+
+bb83:                                             ; preds = %bb78
+  call void @rewind(%struct.FILE* %0) nounwind
+  unreachable
+}
+
+declare %struct.FILE* @"\01_fopen$UNIX2003"(i8*, i8*)
+
+declare i8* @fgets(i8*, i32, %struct.FILE* nocapture) nounwind
+
+declare void @rewind(%struct.FILE* nocapture) nounwind
+
+declare i32 @feof(%struct.FILE* nocapture) nounwind
+
+declare i32 @strcmp(i8* nocapture, i8* nocapture) nounwind readonly