{clang,llvm}_host: adds clang v3.8.1 and llvm v3.8.1 (via Redfoxmoon.)

1 files changed, 99 insertions, 0 deletions

diff --git a/patches/llvm_host/llvm-0004-Fix-ScalarEvolutionExpander-step-scaling-bug.patch b/patches/llvm_host/llvm-0004-Fix-ScalarEvolutionExpander-step-scaling-bug.patch
new file mode 100644
index 00000000..9945bf35
--- /dev/null
+++ b/patches/llvm_host/llvm-0004-Fix-ScalarEvolutionExpander-step-scaling-bug.patch
@@ -0,0 +1,99 @@
+From c8ce9e59a883f452bc538b5f16fb83649472dc3e Mon Sep 17 00:00:00 2001
+From: Keno Fischer <kfischer@college.harvard.edu>
+Date: Wed, 13 Jul 2016 01:28:12 +0000
+Subject: [PATCH] Fix ScalarEvolutionExpander step scaling bug
+
+The expandAddRecExprLiterally function incorrectly transforms
+`[Start + Step * X]` into `Step * [Start + X]` instead of the correct
+transform of `[Step * X] + Start`.
+
+This caused https://github.com/JuliaLang/julia/issues/14704#issuecomment-174126219
+due to what appeared to be sufficiently complicated loop interactions.
+
+Patch by Jameson Nash (jameson@juliacomputing.com).
+
+Reviewers: sanjoy
+Differential Revision: http://reviews.llvm.org/D16505
+
+git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@275239 91177308-0d34-0410-b5e6-96231b3b80d8
+
+Alpine maintainer notes:
+This patch replaces deps/patches/llvm-3.7.1_3.patch from Julia.
+---
+ lib/Analysis/ScalarEvolutionExpander.cpp           |  7 ++++
+ .../ScalarEvolution/incorrect-offset-scaling.ll    | 48 ++++++++++++++++++++++
+ 2 files changed, 55 insertions(+)
+ create mode 100644 test/Analysis/ScalarEvolution/incorrect-offset-scaling.ll
+
+diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp
+index 7716435..77e4ec7 100644
+--- a/lib/Analysis/ScalarEvolutionExpander.cpp
++++ b/lib/Analysis/ScalarEvolutionExpander.cpp
+@@ -1288,6 +1288,13 @@ Value *SCEVExpander::expandAddRecExprLiterally(const SCEVAddRecExpr *S) {
+   if (!SE.dominates(Step, L->getHeader())) {
+     PostLoopScale = Step;
+     Step = SE.getConstant(Normalized->getType(), 1);
++    if (!Start->isZero()) {
++        // The normalization below assumes that Start is constant zero, so if
++        // it isn't re-associate Start to PostLoopOffset.
++        assert(!PostLoopOffset && "Start not-null but PostLoopOffset set?");
++        PostLoopOffset = Start;
++        Start = SE.getConstant(Normalized->getType(), 0);
++    }
+     Normalized =
+       cast<SCEVAddRecExpr>(SE.getAddRecExpr(
+                              Start, Step, Normalized->getLoop(),
+diff --git a/test/Analysis/ScalarEvolution/incorrect-offset-scaling.ll b/test/Analysis/ScalarEvolution/incorrect-offset-scaling.ll
+new file mode 100644
+index 0000000..7ffb093
+--- /dev/null
++++ b/test/Analysis/ScalarEvolution/incorrect-offset-scaling.ll
+@@ -0,0 +1,48 @@
++; RUN: opt -S -loop-reduce < %s | FileCheck %s
++
++target triple = "x86_64-unknown-unknown"
++target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
++
++define void @incorrect_offset_scaling(i64, i64*) {
++top:
++  br label %L
++
++L:                                                ; preds = %idxend.10, %idxend, %L2, %top
++  br i1 undef, label %L, label %L1
++
++L1:                                               ; preds = %L1.preheader, %L2
++  %r13 = phi i64 [ %r1, %L2 ], [ 1, %L ]
++; CHECK:  %lsr.iv = phi i64 [ 0, %L{{[^ ]+}} ], [ %lsr.iv.next, %L2 ]
++; CHECK-NOT:  %lsr.iv = phi i64 [ -1, %L{{[^ ]+}} ], [ %lsr.iv.next, %L2 ]
++; CHECK:  br
++  %r0 = add i64 %r13, -1
++  br label %idxend.8
++
++L2:                                               ; preds = %idxend.8
++  %r1 = add i64 %r13, 1
++  br i1 undef, label %L, label %L1
++
++if6:                                              ; preds = %idxend.8
++  %r2 = add i64 %0, -1
++  %r3 = load i64, i64* %1, align 8
++; CHECK-NOT:  %r2
++; CHECK:  %r3 = load i64
++  br label %ib
++
++idxend.8:                                         ; preds = %L1
++  br i1 undef, label %if6, label %L2
++
++ib:                                               ; preds = %if6
++  %r4 = mul i64 %r3, %r0
++  %r5 = add i64 %r2, %r4
++  %r6 = icmp ult i64 %r5, undef
++; CHECK  %2 = mul i64 %lsr.iv, %r3
++; CHECK  %3 = add i64 %1, -1
++; CHECK  %4 = add i64 %0, %r3
++; CHECK  %r6
++  %r7 = getelementptr i64, i64* undef, i64 %r5
++  store i64 1, i64* %r7, align 8
++; CHECK  %5 = mul i64 %lsr.iv, %r3
++; CHECK  %6 = add i64 %5, -1
++  br label %L
++}