diff options
| -rw-r--r-- | llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp | 3 | ||||
| -rw-r--r-- | llvm/test/CodeGen/AMDGPU/amdgpu-unroll-threshold.ll | 52 |
2 files changed, 54 insertions, 1 deletions
diff --git a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp index a5066a0f669..c51ccf27713 100644 --- a/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp +++ b/llvm/lib/Target/AMDGPU/AMDGPUTargetTransformInfo.cpp @@ -90,7 +90,8 @@ static bool dependsOnLocalPhi(const Loop *L, const Value *Cond, void AMDGPUTTIImpl::getUnrollingPreferences(Loop *L, ScalarEvolution &SE, TTI::UnrollingPreferences &UP) { - UP.Threshold = 300; // Twice the default. + const Function &F = *L->getHeader()->getParent(); + UP.Threshold = AMDGPU::getIntegerAttribute(F, "amdgpu-unroll-threshold", 300); UP.MaxCount = std::numeric_limits<unsigned>::max(); UP.Partial = true; diff --git a/llvm/test/CodeGen/AMDGPU/amdgpu-unroll-threshold.ll b/llvm/test/CodeGen/AMDGPU/amdgpu-unroll-threshold.ll new file mode 100644 index 00000000000..4da11ca7795 --- /dev/null +++ b/llvm/test/CodeGen/AMDGPU/amdgpu-unroll-threshold.ll @@ -0,0 +1,52 @@ +; RUN: opt < %s -S -mtriple=amdgcn-- -basicaa -loop-unroll | FileCheck %s + +; Check that the loop in unroll_default is not fully unrolled using the default +; unroll threshold +; CHECK-LABEL: @unroll_default +; CHECK: entry: +; CHECK: br i1 %cmp +; CHECK: ret void + +; Check that the same loop in unroll_full is fully unrolled when the default +; unroll threshold is increased by use of the amdgpu-unroll-threshold attribute +; CHECK-LABEL: @unroll_full +; CHECK: entry: +; CHECK-NOT: br i1 %cmp +; CHECK: ret void + +@in = internal unnamed_addr global i32* null, align 8 +@out = internal unnamed_addr global i32* null, align 8 + +define void @unroll_default() { +entry: + br label %do.body + +do.body: ; preds = %entry + %i.0 = phi i32 [ 0, %entry ], [ %inc, %do.body ] + %v1 = load i64, i64* bitcast (i32** @in to i64*), align 8 + store i64 %v1, i64* bitcast (i32** @out to i64*), align 8 + %inc = add nsw i32 %i.0, 1 + %cmp = icmp slt i32 %inc, 100 + br i1 %cmp, label %do.body, label %do.end + +do.end: ; preds = %do.body + ret void +} + +define void @unroll_full() #0 { +entry: + br label %do.body + +do.body: ; preds = %entry + %i.0 = phi i32 [ 0, %entry ], [ %inc, %do.body ] + %v1 = load i64, i64* bitcast (i32** @in to i64*), align 8 + store i64 %v1, i64* bitcast (i32** @out to i64*), align 8 + %inc = add nsw i32 %i.0, 1 + %cmp = icmp slt i32 %inc, 100 + br i1 %cmp, label %do.body, label %do.end + +do.end: ; preds = %do.body + ret void +} + +attributes #0 = { "amdgpu-unroll-threshold"="1000" } |
