[AlignmentFromAssumptions] Don't crash just because the target is 32-bit

We used to crash processing any relevant @llvm.assume on a 32-bit target
(because we'd ask SE to subtract expressions of differing types). I've copied
our 'simple.ll' test, but with the data layout from arm-linux-gnueabihf to get
some meaningful test coverage here.

llvm-svn: 217574

2 files changed, 219 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp b/llvm/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
index 7ab16f13811..06c3dfdf637 100644
--- a/llvm/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
+++ b/llvm/lib/Transforms/Scalar/AlignmentFromAssumptions.cpp
@@ -141,6 +141,10 @@ static unsigned getNewAlignment(const SCEV *AASCEV, const SCEV *AlignSCEV,
   const SCEV *PtrSCEV = SE->getSCEV(Ptr);
   const SCEV *DiffSCEV = SE->getMinusSCEV(PtrSCEV, AASCEV);
 
+  // On 32-bit platforms, DiffSCEV might now have type i32 -- we've always
+  // sign-extended OffSCEV to i64, so make sure they agree again.
+  DiffSCEV = SE->getNoopOrSignExtend(DiffSCEV, OffSCEV->getType());
+
   // What we really want to know is the overall offset to the aligned
   // address. This address is displaced by the provided offset.
   DiffSCEV = SE->getMinusSCEV(DiffSCEV, OffSCEV);
diff --git a/llvm/test/Transforms/AlignmentFromAssumptions/simple32.ll b/llvm/test/Transforms/AlignmentFromAssumptions/simple32.ll
new file mode 100644
index 00000000000..166e7ef3893
--- /dev/null
+++ b/llvm/test/Transforms/AlignmentFromAssumptions/simple32.ll
@@ -0,0 +1,215 @@
+target datalayout = "e-m:e-p:32:32-i64:64-v128:64:128-n32-S64"
+; RUN: opt < %s -alignment-from-assumptions -S | FileCheck %s
+
+define i32 @foo(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  %0 = load i32* %a, align 4
+  ret i32 %0
+
+; CHECK-LABEL: @foo
+; CHECK: load i32* {{[^,]+}}, align 32
+; CHECK: ret i32
+}
+
+define i32 @foo2(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %offsetptr = add i64 %ptrint, 24
+  %maskedptr = and i64 %offsetptr, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  %arrayidx = getelementptr inbounds i32* %a, i64 2
+  %0 = load i32* %arrayidx, align 4
+  ret i32 %0
+
+; CHECK-LABEL: @foo2
+; CHECK: load i32* {{[^,]+}}, align 16
+; CHECK: ret i32
+}
+
+define i32 @foo2a(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %offsetptr = add i64 %ptrint, 28
+  %maskedptr = and i64 %offsetptr, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  %arrayidx = getelementptr inbounds i32* %a, i64 -1
+  %0 = load i32* %arrayidx, align 4
+  ret i32 %0
+
+; CHECK-LABEL: @foo2a
+; CHECK: load i32* {{[^,]+}}, align 32
+; CHECK: ret i32
+}
+
+define i32 @goo(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  %0 = load i32* %a, align 4
+  ret i32 %0
+
+; CHECK-LABEL: @goo
+; CHECK: load i32* {{[^,]+}}, align 32
+; CHECK: ret i32
+}
+
+define i32 @hoo(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %r.06 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
+  %0 = load i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %r.06
+  %indvars.iv.next = add i64 %indvars.iv, 8
+  %1 = trunc i64 %indvars.iv.next to i32
+  %cmp = icmp slt i32 %1, 2048
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body
+  %add.lcssa = phi i32 [ %add, %for.body ]
+  ret i32 %add.lcssa
+
+; CHECK-LABEL: @hoo
+; CHECK: load i32* %arrayidx, align 32
+; CHECK: ret i32 %add.lcssa
+}
+
+define i32 @joo(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %indvars.iv = phi i64 [ 4, %entry ], [ %indvars.iv.next, %for.body ]
+  %r.06 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
+  %0 = load i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %r.06
+  %indvars.iv.next = add i64 %indvars.iv, 8
+  %1 = trunc i64 %indvars.iv.next to i32
+  %cmp = icmp slt i32 %1, 2048
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body
+  %add.lcssa = phi i32 [ %add, %for.body ]
+  ret i32 %add.lcssa
+
+; CHECK-LABEL: @joo
+; CHECK: load i32* %arrayidx, align 16
+; CHECK: ret i32 %add.lcssa
+}
+
+define i32 @koo(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
+  %r.06 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
+  %0 = load i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %r.06
+  %indvars.iv.next = add i64 %indvars.iv, 4
+  %1 = trunc i64 %indvars.iv.next to i32
+  %cmp = icmp slt i32 %1, 2048
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body
+  %add.lcssa = phi i32 [ %add, %for.body ]
+  ret i32 %add.lcssa
+
+; CHECK-LABEL: @koo
+; CHECK: load i32* %arrayidx, align 16
+; CHECK: ret i32 %add.lcssa
+}
+
+define i32 @koo2(i32* nocapture %a) nounwind uwtable readonly {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  br label %for.body
+
+for.body:                                         ; preds = %entry, %for.body
+  %indvars.iv = phi i64 [ -4, %entry ], [ %indvars.iv.next, %for.body ]
+  %r.06 = phi i32 [ 0, %entry ], [ %add, %for.body ]
+  %arrayidx = getelementptr inbounds i32* %a, i64 %indvars.iv
+  %0 = load i32* %arrayidx, align 4
+  %add = add nsw i32 %0, %r.06
+  %indvars.iv.next = add i64 %indvars.iv, 4
+  %1 = trunc i64 %indvars.iv.next to i32
+  %cmp = icmp slt i32 %1, 2048
+  br i1 %cmp, label %for.body, label %for.end
+
+for.end:                                          ; preds = %for.body
+  %add.lcssa = phi i32 [ %add, %for.body ]
+  ret i32 %add.lcssa
+
+; CHECK-LABEL: @koo2
+; CHECK: load i32* %arrayidx, align 16
+; CHECK: ret i32 %add.lcssa
+}
+
+define i32 @moo(i32* nocapture %a) nounwind uwtable {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  %0 = bitcast i32* %a to i8*
+  tail call void @llvm.memset.p0i8.i64(i8* %0, i8 0, i64 64, i32 4, i1 false)
+  ret i32 undef
+
+; CHECK-LABEL: @moo
+; CHECK: @llvm.memset.p0i8.i64(i8* %0, i8 0, i64 64, i32 32, i1 false)
+; CHECK: ret i32 undef
+}
+
+define i32 @moo2(i32* nocapture %a, i32* nocapture %b) nounwind uwtable {
+entry:
+  %ptrint = ptrtoint i32* %a to i64
+  %maskedptr = and i64 %ptrint, 31
+  %maskcond = icmp eq i64 %maskedptr, 0
+  tail call void @llvm.assume(i1 %maskcond)
+  %ptrint1 = ptrtoint i32* %b to i64
+  %maskedptr3 = and i64 %ptrint1, 127
+  %maskcond4 = icmp eq i64 %maskedptr3, 0
+  tail call void @llvm.assume(i1 %maskcond4)
+  %0 = bitcast i32* %a to i8*
+  %1 = bitcast i32* %b to i8*
+  tail call void @llvm.memcpy.p0i8.p0i8.i64(i8* %0, i8* %1, i64 64, i32 4, i1 false)
+  ret i32 undef
+
+; CHECK-LABEL: @moo2
+; CHECK: @llvm.memcpy.p0i8.p0i8.i64(i8* %0, i8* %1, i64 64, i32 32, i1 false)
+; CHECK: ret i32 undef
+}
+
+declare void @llvm.assume(i1) nounwind
+
+declare void @llvm.memset.p0i8.i64(i8* nocapture, i8, i64, i32, i1) nounwind
+declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture, i8* nocapture, i64, i32, i1) nounwind
+