70 lines
2.0 KiB
LLVM
70 lines
2.0 KiB
LLVM
; REQUIRES: asserts
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; RUN: opt -S -passes=loop-fusion -loop-fusion-dependence-analysis=da -debug-only=loop-fusion -disable-output < %s 2>&1 | FileCheck %s --check-prefix=CHECK-DA
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; RUN: opt -S -passes=loop-fusion -loop-fusion-dependence-analysis=scev -debug-only=loop-fusion -disable-output < %s 2>&1 | FileCheck %s --check-prefix=CHECK-SCEV
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define void @loop_invariant(i32 %N) {
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; CHECK-DA: Performing Loop Fusion on function loop_invariant
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; CHECK-DA: Safe to fuse due to a loop-invariant non-anti dependency
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; CHECK-SCEV: Performing Loop Fusion on function loop_invariant
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; CHECK-SCEV: Fusion done
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;
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pre1:
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%ptr = alloca i32, align 4
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br label %body1
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body1: ; preds = %pre1, %body1
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%i = phi i32 [%i_next, %body1], [0, %pre1]
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%i_next = add i32 1, %i
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%cond = icmp ne i32 %i, %N
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store i32 3, ptr %ptr
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br i1 %cond, label %body1, label %pre2
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pre2:
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br label %body2
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body2: ; preds = %pre2, %body2
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%i2 = phi i32 [%i_next2, %body2], [0, %pre2]
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%i_next2 = add i32 1, %i2
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%cond2 = icmp ne i32 %i2, %N
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store i32 3, ptr %ptr
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br i1 %cond2, label %body2, label %exit
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exit:
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ret void
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}
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; TODO: improve SCEV check to detect the loop-invariant anti dependence with
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; scalar access and prevent fusion.
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define void @anti_loop_invariant(i32 %N) {
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; CHECK-DA: Performing Loop Fusion on function anti_loop_invariant
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; CHECK-DA: Memory dependencies do not allow fusion!
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; CHECK-SCEV: Performing Loop Fusion on function anti_loop_invariant
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; XFAIL-CHECK-SCEV: Memory dependencies do not allow fusion!
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;
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pre1:
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%ptr = alloca i32, align 4
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store i32 1, ptr %ptr
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br label %body1
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body1: ; preds = %pre1, %body1
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%i = phi i32 [%i_next, %body1], [0, %pre1]
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%i_next = add i32 1, %i
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%cond = icmp ne i32 %i, %N
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%v = load i32, ptr %ptr
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br i1 %cond, label %body1, label %pre2
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pre2:
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br label %body2
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body2: ; preds = %pre2, %body2
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%i2 = phi i32 [%i_next2, %body2], [0, %pre2]
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%i_next2 = add i32 1, %i2
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%cond2 = icmp ne i32 %i2, %N
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store i32 3, ptr %ptr
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br i1 %cond2, label %body2, label %exit
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exit:
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ret void
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}
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