Files
clang-p2996/llvm/test/Analysis/DivergenceAnalysis/AMDGPU/propagate-loop-live-out.ll
Sameer Sahasrabuddhe 11bf7da64a [NewPM] Introduce (GPU)DivergenceAnalysis in the new pass manager
The GPUDivergenceAnalysis is now renamed to just "DivergenceAnalysis"
since there is no conflict with LegacyDivergenceAnalysis. In the
legacy PM, this analysis can only be used through the legacy DA
serving as a wrapper. It is now made available as a pass in the new
PM, and has no relation with the legacy DA.

The new DA currently cannot handle irreducible control flow; its
presence can cause the analysis to run indefinitely. The analysis is
now modified to detect this and report all instructions in the
function as divergent. This is super conservative, but allows the
analysis to be used without hanging the compiler.

Reviewed By: aeubanks

Differential Revision: https://reviews.llvm.org/D96615
2021-02-16 10:26:45 +05:30

50 lines
1.8 KiB
LLVM

; RUN: opt -mtriple amdgcn-unknown-amdhsa -enable-new-pm=0 -analyze -divergence -use-gpu-divergence-analysis %s | FileCheck %s
; RUN: opt -mtriple amdgcn-unknown-amdhsa -passes='print<divergence>' -disable-output %s 2>&1 | FileCheck %s
; CHECK: bb6:
; CHECK: DIVERGENT: %.126.i355.i = phi i1 [ false, %bb5 ], [ true, %bb4 ]
; CHECK: DIVERGENT: br i1 %.126.i355.i, label %bb7, label %bb8
; Function Attrs: nounwind readnone speculatable
declare i32 @llvm.amdgcn.workitem.id.x() #0
define protected amdgpu_kernel void @_Z23krnl_GPUITSFitterKerneli() {
bb0:
%i4 = call i32 @llvm.amdgcn.workitem.id.x()
%i5 = icmp eq i32 %i4, -1
br label %bb1
bb1: ; preds = %bb3, %bb0
%lsr.iv = phi i32 [ %i1, %bb3 ], [ 7, %bb0 ]
br i1 %i5, label %bb2, label %bb3
bb2: ; preds = %bb1
%lsr.iv.next = add nsw i32 %lsr.iv, -1
%i14 = icmp eq i32 %lsr.iv.next, 0
br label %bb3
bb3: ; preds = %bb2, %bb1
%i1 = phi i32 [ %lsr.iv.next, %bb2 ], [ 0, %bb1 ]
%i2 = phi i1 [ false, %bb2 ], [ true, %bb1 ]
%i3 = phi i1 [ %i14, %bb2 ], [ true, %bb1 ]
br i1 %i3, label %bb4, label %bb1
bb4: ; preds = %bb3
br i1 %i2, label %bb5, label %bb6
bb5: ; preds = %bb4
br label %bb6
bb6: ; preds = %bb5, %bb4
%.126.i355.i = phi i1 [ false, %bb5 ], [ true, %bb4 ]
br i1 %.126.i355.i, label %bb7, label %bb8
bb7: ; preds = %bb6
br label %bb8
bb8: ; preds = %bb7, %bb6
ret void
}
attributes #0 = { nounwind readnone speculatable }