From c94b63ba840d77d79e0eec476b09ea146c4f4fab Mon Sep 17 00:00:00 2001 From: Hans Wennborg Date: Fri, 22 Jul 2016 14:08:45 +0000 Subject: [PATCH] Merging r276181: ------------------------------------------------------------------------ r276181 | majnemer | 2016-07-20 14:05:01 -0700 (Wed, 20 Jul 2016) | 6 lines [GVNHoist] Don't hoist PHI nodes We hoisted PHIs without respecting their special insertion point in the block, leading to verfier errors. This fixes PR28626. ------------------------------------------------------------------------ git-svn-id: https://llvm.org/svn/llvm-project/llvm/branches/release_39@276418 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/GVNHoist.cpp | 12 ++++++--- test/Transforms/GVN/pr28626.ll | 42 ++++++++++++++++++++++++++++++ 2 files changed, 50 insertions(+), 4 deletions(-) create mode 100644 test/Transforms/GVN/pr28626.ll diff --git a/lib/Transforms/Scalar/GVNHoist.cpp b/lib/Transforms/Scalar/GVNHoist.cpp index c53263ac194..809d1ed6142 100644 --- a/lib/Transforms/Scalar/GVNHoist.cpp +++ b/lib/Transforms/Scalar/GVNHoist.cpp @@ -589,16 +589,20 @@ public: bool makeOperandsAvailable(Instruction *Repl, BasicBlock *HoistPt) const { // Check whether the GEP of a ld/st can be synthesized at HoistPt. - Instruction *Gep = nullptr; + GetElementPtrInst *Gep = nullptr; Instruction *Val = nullptr; if (auto *Ld = dyn_cast(Repl)) - Gep = dyn_cast(Ld->getPointerOperand()); + Gep = dyn_cast(Ld->getPointerOperand()); if (auto *St = dyn_cast(Repl)) { - Gep = dyn_cast(St->getPointerOperand()); + Gep = dyn_cast(St->getPointerOperand()); Val = dyn_cast(St->getValueOperand()); } - if (!Gep || !isa(Gep)) + if (!Gep) + return false; + + // PHIs may only be inserted at the start of a block. + if (Val && isa(Val)) return false; // Check whether we can compute the Gep at HoistPt. diff --git a/test/Transforms/GVN/pr28626.ll b/test/Transforms/GVN/pr28626.ll new file mode 100644 index 00000000000..742d968be36 --- /dev/null +++ b/test/Transforms/GVN/pr28626.ll @@ -0,0 +1,42 @@ +; RUN: opt -S -gvn-hoist < %s | FileCheck %s +target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128" +target triple = "x86_64-unknown-linux-gnu" + +define void @test1(i1 %a, i1** %d) { +entry: + %0 = load i1*, i1** %d, align 8 + br i1 %a, label %if.then, label %if.else + +if.then: ; preds = %entry + br label %if.end + +if.else: ; preds = %entry + br label %if.end + +if.end: ; preds = %if.else, %if.then + %c.0 = phi i1 [ 1, %if.then ], [ 0, %if.else ] + br i1 %c.0, label %if.then2, label %if.else3 + +if.then2: ; preds = %if.end + %rc = getelementptr inbounds i1, i1* %0, i64 0 + store i1 %c.0, i1* %rc, align 4 + br label %if.end6 + +if.else3: ; preds = %if.end + %rc5 = getelementptr inbounds i1, i1* %0, i64 0 + store i1 %c.0, i1* %rc5, align 4 + br label %if.end6 + +if.end6: ; preds = %if.else3, %if.then2 + ret void +} + +; CHECK-LABEL: define void @test1( +; CHECK: %[[load:.*]] = load i1*, i1** %d, align 8 +; CHECK: %[[phi:.*]] = phi i1 [ true, {{.*}} ], [ false, {{.*}} ] + +; CHECK: %[[gep0:.*]] = getelementptr inbounds i1, i1* %[[load]], i64 0 +; CHECK: store i1 %[[phi]], i1* %[[gep0]], align 4 + +; CHECK: %[[gep1:.*]] = getelementptr inbounds i1, i1* %[[load]], i64 0 +; CHECK: store i1 %[[phi]], i1* %[[gep1]], align 4 -- 2.49.0