From d10aa6f8b2b0ea0464c9ee066d8b69e582f171dd Mon Sep 17 00:00:00 2001 From: Mark Heffernan Date: Thu, 24 Jul 2014 22:36:40 +0000 Subject: [PATCH] After unrolling a loop with llvm.loop.unroll.count metadata (unroll factor hint) the loop unroller replaces the llvm.loop.unroll.count metadata with llvm.loop.unroll.disable metadata to prevent any subsequent unrolling passes from unrolling more than the hint indicates. This patch fixes an issue where loop unrolling could be disabled for other loops as well which share the same llvm.loop metadata. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@213900 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/LoopUnrollPass.cpp | 1 - .../LoopUnroll/unroll-pragmas-disabled.ll | 60 +++++++++++++++++-- 2 files changed, 54 insertions(+), 7 deletions(-) diff --git a/lib/Transforms/Scalar/LoopUnrollPass.cpp b/lib/Transforms/Scalar/LoopUnrollPass.cpp index 2e94a44cad7..3f12209e144 100644 --- a/lib/Transforms/Scalar/LoopUnrollPass.cpp +++ b/lib/Transforms/Scalar/LoopUnrollPass.cpp @@ -302,7 +302,6 @@ static void SetLoopAlreadyUnrolled(Loop *L) { // Set operand 0 to refer to the loop id itself. NewLoopID->replaceOperandWith(0, NewLoopID); L->setLoopID(NewLoopID); - LoopID->replaceAllUsesWith(NewLoopID); } unsigned LoopUnroll::selectUnrollCount( diff --git a/test/Transforms/LoopUnroll/unroll-pragmas-disabled.ll b/test/Transforms/LoopUnroll/unroll-pragmas-disabled.ll index 04f8f483af0..db18f25c73e 100644 --- a/test/Transforms/LoopUnroll/unroll-pragmas-disabled.ll +++ b/test/Transforms/LoopUnroll/unroll-pragmas-disabled.ll @@ -11,9 +11,9 @@ target triple = "x86_64-unknown-linux-gnu" ; Unroll count metadata should be replaced with unroll(disable). Vectorize ; metadata should be untouched. ; -; CHECK-LABEL: @loop1( +; CHECK-LABEL: @unroll_count_4( ; CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[LOOP_1:.*]] -define void @loop1(i32* nocapture %a) { +define void @unroll_count_4(i32* nocapture %a) { entry: br label %for.body @@ -42,9 +42,9 @@ for.end: ; preds = %for.body ; because the trip count is dynamic. The full unroll metadata should remain ; after unrolling. ; -; CHECK-LABEL: @loop2( +; CHECK-LABEL: @unroll_full( ; CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[LOOP_2:.*]] -define void @loop2(i32* nocapture %a, i32 %b) { +define void @unroll_full(i32* nocapture %a, i32 %b) { entry: %cmp3 = icmp sgt i32 %b, 0 br i1 %cmp3, label %for.body, label %for.end, !llvm.loop !5 @@ -70,9 +70,9 @@ for.end: ; preds = %for.body, %entry ; ; Unroll metadata should not change. ; -; CHECK-LABEL: @loop3( +; CHECK-LABEL: @unroll_disable( ; CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[LOOP_3:.*]] -define void @loop3(i32* nocapture %a) { +define void @unroll_disable(i32* nocapture %a) { entry: br label %for.body @@ -92,6 +92,52 @@ for.end: ; preds = %for.body !7 = metadata !{metadata !7, metadata !8} !8 = metadata !{metadata !"llvm.loop.unroll.disable"} +; This function contains two loops which share the same llvm.loop metadata node +; with an llvm.loop.unroll.count 2 hint. Both loops should be unrolled. This +; verifies that adding disable metadata to a loop after unrolling doesn't affect +; other loops which previously shared the same llvm.loop metadata. +; +; CHECK-LABEL: @shared_metadata( +; CHECK: store i32 +; CHECK: store i32 +; CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[LOOP_4:.*]] +; CHECK: store i32 +; CHECK: store i32 +; CHECK: br i1 {{.*}}, label {{.*}}, label {{.*}}, !llvm.loop ![[LOOP_5:.*]] +define void @shared_metadata(i32* nocapture %List) #0 { +entry: + br label %for.body3 + +for.body3: ; preds = %for.body3, %entry + %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body3 ] + %arrayidx = getelementptr inbounds i32* %List, i64 %indvars.iv + %0 = load i32* %arrayidx, align 4 + %add4 = add nsw i32 %0, 10 + store i32 %add4, i32* %arrayidx, align 4 + %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 + %exitcond = icmp eq i64 %indvars.iv.next, 4 + br i1 %exitcond, label %for.body3.1.preheader, label %for.body3, !llvm.loop !9 + +for.body3.1.preheader: ; preds = %for.body3 + br label %for.body3.1 + +for.body3.1: ; preds = %for.body3.1.preheader, %for.body3.1 + %indvars.iv.1 = phi i64 [ %1, %for.body3.1 ], [ 0, %for.body3.1.preheader ] + %1 = add nsw i64 %indvars.iv.1, 1 + %arrayidx.1 = getelementptr inbounds i32* %List, i64 %1 + %2 = load i32* %arrayidx.1, align 4 + %add4.1 = add nsw i32 %2, 10 + store i32 %add4.1, i32* %arrayidx.1, align 4 + %exitcond.1 = icmp eq i64 %1, 4 + br i1 %exitcond.1, label %for.inc5.1, label %for.body3.1, !llvm.loop !9 + +for.inc5.1: ; preds = %for.body3.1 + ret void +} +!9 = metadata !{metadata !9, metadata !10} +!10 = metadata !{metadata !"llvm.loop.unroll.count", i32 2} + + ; CHECK: ![[LOOP_1]] = metadata !{metadata ![[LOOP_1]], metadata ![[VEC_ENABLE:.*]], metadata ![[WIDTH_8:.*]], metadata ![[UNROLL_DISABLE:.*]]} ; CHECK: ![[VEC_ENABLE]] = metadata !{metadata !"llvm.loop.vectorize.enable", i1 true} ; CHECK: ![[WIDTH_8]] = metadata !{metadata !"llvm.loop.vectorize.width", i32 8} @@ -99,3 +145,5 @@ for.end: ; preds = %for.body ; CHECK: ![[LOOP_2]] = metadata !{metadata ![[LOOP_2]], metadata ![[UNROLL_FULL:.*]]} ; CHECK: ![[UNROLL_FULL]] = metadata !{metadata !"llvm.loop.unroll.full"} ; CHECK: ![[LOOP_3]] = metadata !{metadata ![[LOOP_3]], metadata ![[UNROLL_DISABLE:.*]]} +; CHECK: ![[LOOP_4]] = metadata !{metadata ![[LOOP_4]], metadata ![[UNROLL_DISABLE:.*]]} +; CHECK: ![[LOOP_5]] = metadata !{metadata ![[LOOP_5]], metadata ![[UNROLL_DISABLE:.*]]} -- 2.34.1