[llvm] 5f2b787 - NFC. Add tests exposing missing analysis invalidation in LoopPredication.

[Daniil Suchkov via llvm-commits]

Author: Daniil Suchkov
Date: 2021-09-16T22:49:55Z
New Revision: 5f2b7879f16ad5023f0684febeb0a20f7d53e4a8

URL: https://github.com/llvm/llvm-project/commit/5f2b7879f16ad5023f0684febeb0a20f7d53e4a8
DIFF: https://github.com/llvm/llvm-project/commit/5f2b7879f16ad5023f0684febeb0a20f7d53e4a8.diff

LOG: NFC. Add tests exposing missing analysis invalidation in LoopPredication.

Added: 
    llvm/test/Transforms/LoopPredication/invalidate-analyses.ll

Modified: 
    

Removed: 
    


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diff  --git a/llvm/test/Transforms/LoopPredication/invalidate-analyses.ll b/llvm/test/Transforms/LoopPredication/invalidate-analyses.ll
new file mode 100644
index 0000000000000..9c1812a9ae9d6
--- /dev/null
+++ b/llvm/test/Transforms/LoopPredication/invalidate-analyses.ll
@@ -0,0 +1,166 @@
+; RUN: opt -S -passes='require<scalar-evolution>,loop-mssa(loop-predication)' -debug-pass-manager < %s 2>&1 | FileCheck %s
+
+; FIXME: We should invalidate PreservedCFGCheckerAnalysis after LoopPredicationPass!
+; NOTE: PreservedCFGCheckerAnalysis is an arbitrary analysis that just happens
+;       to be calculated before this pass and isn't preserved by it. If after
+;       your change this analysis is preserved by the pass, please update this
+;       test some other analysis that isn't preserved.
+
+; CHECK: Running analysis: PreservedCFGCheckerAnalysis on drop_a_wc_and_leave_early
+; CHECK: Running pass: LoopPredicationPass on Loop at depth 1 containing: %loop<header><exiting>,%guarded<exiting>,%guarded2<latch><exiting>
+; CHECK-NEXT: Running analysis: PreservedCFGCheckerAnalysis on drop_a_wc_and_leave
+; CHECK: Running pass: LoopPredicationPass on Loop at depth 1 containing: %loop<header><exiting>,%guarded<exiting>,%guarded2<latch><exiting>
+; CHECK-NEXT: Running pass: VerifierPass
+
+
+; This test makes the pass drop its attempts to optimize the exit condition in
+; `%loop` BB by using unanalyzable `%cond_0` as an exit condition.
+define i64 @drop_a_wc_and_leave_early(i64 %length, i64 %n, i1 %cond_0, i1 %cond_1) {
+; Make sure the pass has only replaced `%wc2` with `true` in the definition of `%wb_cond`.
+; CHECK-LABEL: define i64 @drop_a_wc_and_leave_early(i64 %length, i64 %n, i1 %cond_0, i1 %cond_1) {
+; CHECK-NEXT: entry:
+; CHECK-NEXT:   %wc1 = call i1 @llvm.experimental.widenable.condition()
+; CHECK-NEXT:   %wc2 = call i1 @llvm.experimental.widenable.condition()
+; CHECK-NEXT:   %exiplicit_guard_cond = and i1 %cond_0, %wc1
+; CHECK-NEXT:   br i1 %exiplicit_guard_cond, label %loop.preheader, label %deopt, !prof !0
+; CHECK:      deopt:
+; CHECK-NEXT:   %deoptret = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+; CHECK-NEXT:   ret i64 %deoptret
+; CHECK:      loop.preheader:
+; CHECK-NEXT:   br label %loop
+; CHECK:      loop:
+; CHECK-NEXT:   %i = phi i64 [ %i.next, %guarded2 ], [ 0, %loop.preheader ]
+; CHECK-NEXT:   br i1 %cond_0, label %guarded, label %deopt2, !prof !0
+; CHECK:      deopt2:
+; CHECK-NEXT:   %deoptret2 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+; CHECK-NEXT:   ret i64 %deoptret2
+; CHECK:      guarded:
+; CHECK-NEXT:   %wb_cond = and i1 %cond_1, true
+; CHECK-NEXT:   br i1 %wb_cond, label %guarded2, label %deopt3, !prof !0
+; CHECK:      deopt3:
+; CHECK-NEXT:   %deoptret3 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+; CHECK-NEXT:   ret i64 %deoptret3
+; CHECK:      guarded2:
+; CHECK-NEXT:   %i.next = add nuw i64 %i, 1
+; CHECK-NEXT:   %continue = icmp ult i64 %i.next, %n
+; CHECK-NEXT:   br i1 %continue, label %loop, label %exit
+; CHECK:      exit:
+; CHECK-NEXT:   ret i64 0
+; CHECK-NEXT: }
+
+entry:
+  %wc1 = call i1 @llvm.experimental.widenable.condition()
+  %wc2 = call i1 @llvm.experimental.widenable.condition()
+  %exiplicit_guard_cond = and i1 %cond_0, %wc1
+  br i1 %exiplicit_guard_cond, label %loop.preheader, label %deopt, !prof !0
+
+deopt:
+  %deoptret = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+  ret i64 %deoptret
+
+loop.preheader:
+  br label %loop
+
+loop:
+  %i = phi i64 [ %i.next, %guarded2 ], [ 0, %loop.preheader ]
+  br i1 %cond_0, label %guarded, label %deopt2, !prof !0
+
+deopt2:
+  %deoptret2 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+  ret i64 %deoptret2
+
+guarded:
+  %wb_cond = and i1 %cond_1, %wc2
+  br i1 %wb_cond, label %guarded2, label %deopt3, !prof !0
+
+deopt3:
+  %deoptret3 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+  ret i64 %deoptret3
+
+guarded2:
+  %i.next = add nuw i64 %i, 1
+  %continue = icmp ult i64 %i.next, %n
+  br i1 %continue, label %loop, label %exit
+
+exit:
+  ret i64 0
+}
+
+; This test makes the pass drop its attempts to optimize the exit condition in
+; `%loop` BB by using trivial `false` as an exit condition.
+define i64 @drop_a_wc_and_leave(i64 %n, i1 %cond_0, i1 %cond_1) {
+; Make sure the pass has only replaced `%wc2` with `true` in the definition of `%wb_cond`.
+; CHECK-LABEL: define i64 @drop_a_wc_and_leave(i64 %n, i1 %cond_0, i1 %cond_1) {
+; CHECK-NEXT: entry:
+; CHECK-NEXT:   %wc1 = call i1 @llvm.experimental.widenable.condition()
+; CHECK-NEXT:   %wc2 = call i1 @llvm.experimental.widenable.condition()
+; CHECK-NEXT:   %exiplicit_guard_cond = and i1 %cond_0, %wc1
+; CHECK-NEXT:   br i1 %exiplicit_guard_cond, label %loop.preheader, label %deopt, !prof !0
+; CHECK:      deopt:
+; CHECK-NEXT:   %deoptret = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+; CHECK-NEXT:   ret i64 %deoptret
+; CHECK:      loop.preheader:
+; CHECK-NEXT:   br label %loop
+; CHECK:      loop:
+; CHECK-NEXT:   %i = phi i64 [ %i.next, %guarded2 ], [ 0, %loop.preheader ]
+; CHECK-NEXT:   br i1 false, label %guarded, label %deopt2, !prof !0
+; CHECK:      deopt2:
+; CHECK-NEXT:   %deoptret2 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+; CHECK-NEXT:   ret i64 %deoptret2
+; CHECK:      guarded:
+; CHECK-NEXT:   %wb_cond = and i1 %cond_1, true
+; CHECK-NEXT:   br i1 %wb_cond, label %guarded2, label %deopt3, !prof !0
+; CHECK:      deopt3:
+; CHECK-NEXT:   %deoptret3 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+; CHECK-NEXT:   ret i64 %deoptret3
+; CHECK:      guarded2:
+; CHECK-NEXT:   %i.next = add nuw i64 %i, 1
+; CHECK-NEXT:   %continue = icmp ult i64 %i.next, %n
+; CHECK-NEXT:   br i1 %continue, label %loop, label %exit
+; CHECK:      exit:
+; CHECK-NEXT:   ret i64 0
+; CHECK-NEXT: }
+
+entry:
+  %wc1 = call i1 @llvm.experimental.widenable.condition()
+  %wc2 = call i1 @llvm.experimental.widenable.condition()
+  %exiplicit_guard_cond = and i1 %cond_0, %wc1
+  br i1 %exiplicit_guard_cond, label %loop.preheader, label %deopt, !prof !0
+
+deopt:
+  %deoptret = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+  ret i64 %deoptret
+
+loop.preheader:
+  br label %loop
+
+loop:
+  %i = phi i64 [ %i.next, %guarded2 ], [ 0, %loop.preheader ]
+  br i1 false, label %guarded, label %deopt2, !prof !0
+
+deopt2:
+  %deoptret2 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+  ret i64 %deoptret2
+
+guarded:
+  %wb_cond = and i1 %cond_1, %wc2
+  br i1 %wb_cond, label %guarded2, label %deopt3, !prof !0
+
+deopt3:
+  %deoptret3 = call i64 (...) @llvm.experimental.deoptimize.i64() [ "deopt"() ]
+  ret i64 %deoptret3
+
+guarded2:
+  %i.next = add nuw i64 %i, 1
+  %continue = icmp ult i64 %i.next, %n
+  br i1 %continue, label %loop, label %exit
+
+exit:
+  ret i64 0
+}
+
+
+declare i1 @llvm.experimental.widenable.condition()
+declare i64 @llvm.experimental.deoptimize.i64(...)
+
+!0 = !{!"branch_weights", i64 1048576, i64 1}