[llvm] r314857 - [AArch64] Use LateSimplifyCFG after expanding atomic operations.
Balaram Makam via llvm-commits
llvm-commits at lists.llvm.org
Tue Oct 3 15:39:24 PDT 2017
Author: bmakam
Date: Tue Oct 3 15:39:24 2017
New Revision: 314857
URL: http://llvm.org/viewvc/llvm-project?rev=314857&view=rev
Log:
[AArch64] Use LateSimplifyCFG after expanding atomic operations.
Summary:
After r308422 we defer optimizations that can destroy loop canonical forms to
LateSimplifyCFG. Running LateSimplifyCFG after expanding atomic operations
can exploit more control-flow opportunities.
Reviewers: mcrosier, t.p.northover, efriedma
Reviewed By: efriedma
Subscribers: aemerson, rengolin, javed.absar, llvm-commits, kristof.beyls
Differential Revision: https://reviews.llvm.org/D38262
Modified:
llvm/trunk/lib/Target/AArch64/AArch64TargetMachine.cpp
llvm/trunk/test/CodeGen/AArch64/aarch64-loop-gep-opt.ll
llvm/trunk/test/CodeGen/AArch64/cmpxchg-idioms.ll
Modified: llvm/trunk/lib/Target/AArch64/AArch64TargetMachine.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/AArch64/AArch64TargetMachine.cpp?rev=314857&r1=314856&r2=314857&view=diff
==============================================================================
--- llvm/trunk/lib/Target/AArch64/AArch64TargetMachine.cpp (original)
+++ llvm/trunk/lib/Target/AArch64/AArch64TargetMachine.cpp Tue Oct 3 15:39:24 2017
@@ -365,7 +365,7 @@ void AArch64PassConfig::addIRPasses() {
// determine whether it succeeded. We can exploit existing control-flow in
// ldrex/strex loops to simplify this, but it needs tidying up.
if (TM->getOptLevel() != CodeGenOpt::None && EnableAtomicTidy)
- addPass(createCFGSimplificationPass());
+ addPass(createLateCFGSimplificationPass());
// Run LoopDataPrefetch
//
Modified: llvm/trunk/test/CodeGen/AArch64/aarch64-loop-gep-opt.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AArch64/aarch64-loop-gep-opt.ll?rev=314857&r1=314856&r2=314857&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AArch64/aarch64-loop-gep-opt.ll (original)
+++ llvm/trunk/test/CodeGen/AArch64/aarch64-loop-gep-opt.ll Tue Oct 3 15:39:24 2017
@@ -19,9 +19,9 @@ entry:
do.body.i:
; CHECK-LABEL: do.body.i:
-; CHECK: %uglygep1 = getelementptr i8, i8* %uglygep, i64 %3
-; CHECK-NEXT: %4 = bitcast i8* %uglygep1 to i32*
-; CHECK-NOT: %uglygep1 = getelementptr i8, i8* %uglygep, i64 1032
+; CHECK: %uglygep2 = getelementptr i8, i8* %uglygep, i64 %3
+; CHECK-NEXT: %4 = bitcast i8* %uglygep2 to i32*
+; CHECK-NOT: %uglygep2 = getelementptr i8, i8* %uglygep, i64 1032
%0 = phi i32 [ 256, %entry ], [ %.be, %do.body.i.backedge ]
Modified: llvm/trunk/test/CodeGen/AArch64/cmpxchg-idioms.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/AArch64/cmpxchg-idioms.ll?rev=314857&r1=314856&r2=314857&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/AArch64/cmpxchg-idioms.ll (original)
+++ llvm/trunk/test/CodeGen/AArch64/cmpxchg-idioms.ll Tue Oct 3 15:39:24 2017
@@ -91,3 +91,63 @@ end:
declare void @bar()
declare void @baz()
+
+define i1 @test_conditional2(i32 %a, i32 %b, i32* %c) {
+; CHECK-LABEL: test_conditional2:
+; CHECK: [[LOOP:LBB[0-9]+_[0-9]+]]:
+; CHECK: ldaxr [[LOADED:w[0-9]+]], [x19]
+; CHECK: cmp [[LOADED]], w21
+; CHECK: b.ne [[FAILED:LBB[0-9]+_[0-9]+]]
+
+; CHECK: stlxr [[STATUS:w[0-9]+]], w20, [x19]
+; CHECK: cbnz [[STATUS]], [[LOOP]]
+; CHECK: orr [[STATUS]], wzr, #0x1
+; CHECK: b [[PH:LBB[0-9]+_[0-9]+]]
+
+; CHECK: [[FAILED]]:
+; CHECK-NOT: cmp {{w[0-9]+}}, {{w[0-9]+}}
+
+; verify the preheader is simplified by latesimplifycfg.
+; CHECK: [[PH]]:
+; CHECK: orr w22, wzr, #0x2
+; CHECK-NOT: orr w22, wzr, #0x4
+; CHECK-NOT: cmn w22, #4
+; CHECK: b [[LOOP2:LBB[0-9]+_[0-9]+]]
+; CHECK-NOT: b.ne [[LOOP2]]
+; CHECK-NOT: b {{LBB[0-9]+_[0-9]+}}
+; CHECK: bl _foo
+entry:
+ %pair = cmpxchg i32* %c, i32 %a, i32 %b seq_cst seq_cst
+ %success = extractvalue { i32, i1 } %pair, 1
+ br label %for.cond
+
+for.cond: ; preds = %if.end, %entry
+ %i.0 = phi i32 [ 2, %entry ], [ %dec, %if.end ]
+ %changed.0.off0 = phi i1 [ %success, %entry ], [ %changed.1.off0, %if.end ]
+ %dec = add nsw i32 %i.0, -1
+ %tobool = icmp eq i32 %i.0, 0
+ br i1 %tobool, label %for.cond.cleanup, label %for.body
+
+for.cond.cleanup: ; preds = %for.cond
+ %changed.0.off0.lcssa = phi i1 [ %changed.0.off0, %for.cond ]
+ ret i1 %changed.0.off0.lcssa
+
+for.body: ; preds = %for.cond
+ %or = or i32 %a, %b
+ %idxprom = sext i32 %dec to i64
+ %arrayidx = getelementptr inbounds i32, i32* %c, i64 %idxprom
+ %0 = load i32, i32* %arrayidx, align 4
+ %cmp = icmp eq i32 %or, %0
+ br i1 %cmp, label %if.end, label %if.then
+
+if.then: ; preds = %for.body
+ store i32 %or, i32* %arrayidx, align 4
+ tail call void @foo()
+ br label %if.end
+
+if.end: ; preds = %for.body, %if.then
+ %changed.1.off0 = phi i1 [ false, %if.then ], [ %changed.0.off0, %for.body ]
+ br label %for.cond
+}
+
+declare void @foo()
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