Revert "[memcpyopt] Teach memcpyopt to optimize across basic blocks"

This reverts r321138. It seems there are still underlying issues with
memdep. PR35519 seems to still be present if debug info is enabled. We
end up losing a memcpy. Somehow during store to memset merging, we
insert the memset after the memcpy or fail to update the memdep analysis
to account for the newly inserted memset of a pair.

Reduced test case:

  #include <assert.h>
  #include <stdio.h>
  #include <string>
  #include <utility>
  #include <vector>

  void do_push_back(
      std::vector<std::pair<std::string, std::vector<std::string>>>* crls) {
    crls->push_back(std::make_pair(std::string(), std::vector<std::string>()));
  }

  int __attribute__((optnone)) main() {
    // Put some data in the vector and then remove it so we take the push_back
    // fast path.
    std::vector<std::pair<std::string, std::vector<std::string>>> crl_set;
    crl_set.push_back({"asdf", {}});
    crl_set.pop_back();
    printf("first word in vector storage: %p\n", *(void**)crl_set.data());

    // Do the push_back which may fail to initialize the data.
    do_push_back(&crl_set);
    auto* first = &crl_set.back().first;
    printf("first word in vector storage (should be zero): %p\n",
           *(void**)crl_set.data());
    assert(first->empty());
    puts("ok");
  }

Compile with libc++, enable optimizations, and enable debug info:
$ clang++ -stdlib=libc++ -g -O2 t.cpp -o t.exe -Wl,-rpath=llvm/build/lib

This program will assert with this change.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@321510 91177308-0d34-0410-b5e6-96231b3b80d8

4 files changed, 0 insertions, 243 deletions

diff --git a/test/Transforms/MemCpyOpt/memcpy-invoke-memcpy.ll b/test/Transforms/MemCpyOpt/memcpy-invoke-memcpy.ll
deleted file mode 100644
index e3d1f6dd2b1..00000000000
--- a/test/Transforms/MemCpyOpt/memcpy-invoke-memcpy.ll
+++ /dev/null
@@ -1,48 +0,0 @@
-; RUN: opt < %s -memcpyopt -S | FileCheck %s
-; Test memcpy-memcpy dependencies across invoke edges.
-
-; Test that memcpyopt works across the non-unwind edge of an invoke.
-
-define hidden void @test_normal(i8* noalias %dst, i8* %src) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
-entry:
-  %temp = alloca i8, i32 64
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %temp, i8* nonnull %src, i64 64, i32 8, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %temp, i8* nonnull %src, i64 64, i32 8, i1 false)
-  invoke void @invoke_me()
-          to label %try.cont unwind label %lpad
-
-lpad:
-  landingpad { i8*, i32 }
-          catch i8* null
-  ret void
-
-try.cont:
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %temp, i64 64, i32 8, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %src, i64 64, i32 8, i1 false)
-  ret void
-}
-
-; Test that memcpyopt works across the unwind edge of an invoke.
-
-define hidden void @test_unwind(i8* noalias %dst, i8* %src) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
-entry:
-  %temp = alloca i8, i32 64
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %temp, i8* nonnull %src, i64 64, i32 8, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %temp, i8* nonnull %src, i64 64, i32 8, i1 false)
-  invoke void @invoke_me()
-          to label %try.cont unwind label %lpad
-
-lpad:
-  landingpad { i8*, i32 }
-          catch i8* null
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %temp, i64 64, i32 8, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %src, i64 64, i32 8, i1 false)
-  ret void
-
-try.cont:
-  ret void
-}
-
-declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i32, i1)
-declare i32 @__gxx_personality_v0(...)
-declare void @invoke_me() readnone
diff --git a/test/Transforms/MemCpyOpt/merge-into-memset.ll b/test/Transforms/MemCpyOpt/merge-into-memset.ll
deleted file mode 100644
index fc31038a4e6..00000000000
--- a/test/Transforms/MemCpyOpt/merge-into-memset.ll
+++ /dev/null
@@ -1,45 +0,0 @@
-; RUN: opt < %s -memcpyopt -S | FileCheck %s
-; Update cached non-local dependence information when merging stores into memset.
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-
-; Don't delete the memcpy in %if.then, even though it depends on an instruction
-; which will be deleted.
-
-; CHECK-LABEL: @foo
-define void @foo(i1 %c, i8* %d, i8* %e, i8* %f) {
-entry:
-  %tmp = alloca [50 x i8], align 8
-  %tmp4 = bitcast [50 x i8]* %tmp to i8*
-  %tmp1 = getelementptr inbounds i8, i8* %tmp4, i64 1
-  call void @llvm.memset.p0i8.i64(i8* nonnull %d, i8 0, i64 10, i32 1, i1 false), !dbg !5
-  store i8 0, i8* %tmp4, align 8, !dbg !5
-; CHECK: call void @llvm.memset.p0i8.i64(i8* nonnull %d, i8 0, i64 10, i32 1, i1 false), !dbg !5
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* nonnull %tmp1, i8* nonnull %d, i64 10, i32 1, i1 false)
-  br i1 %c, label %if.then, label %exit
-
-if.then:
-; CHECK: if.then:
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %f, i8* nonnull %tmp4, i64 30, i32 8, i1 false)
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %f, i8* nonnull %tmp4, i64 30, i32 8, i1 false)
-  br label %exit
-
-exit:
-  ret void
-}
-
-declare void @llvm.memcpy.p0i8.p0i8.i64(i8*, i8*, i64, i32, i1)
-declare void @llvm.memset.p0i8.i64(i8*, i8, i64, i32, i1)
-
-!llvm.dbg.cu = !{!0}
-!llvm.module.flags = !{!3, !4}
-
-!0 = distinct !DICompileUnit(language: DW_LANG_Rust, file: !1, isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
-!1 = !DIFile(filename: "t.rs", directory: "/tmp")
-!2 = !{}
-!3 = !{i32 2, !"Dwarf Version", i32 4}
-!4 = !{i32 2, !"Debug Info Version", i32 3}
-!5 = !DILocation(line: 8, column: 5, scope: !6)
-!6 = distinct !DISubprogram(name: "bar", scope: !1, file: !1, line: 5, type: !7, isLocal: false, isDefinition: true, scopeLine: 5, flags: DIFlagPrototyped, isOptimized: false, unit: !0, variables: !2)
-!7 = !DISubroutineType(types: !8)
-!8 = !{null}
diff --git a/test/Transforms/MemCpyOpt/mixed-sizes.ll b/test/Transforms/MemCpyOpt/mixed-sizes.ll
deleted file mode 100644
index 9091fe7f56c..00000000000
--- a/test/Transforms/MemCpyOpt/mixed-sizes.ll
+++ /dev/null
@@ -1,36 +0,0 @@
-; RUN: opt < %s -memcpyopt -S | FileCheck %s
-; Handle memcpy-memcpy dependencies of differing sizes correctly.
-
-target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-
-; Don't delete the second memcpy, even though there's an earlier
-; memcpy with a larger size from the same address.
-
-; CHECK-LABEL: @foo
-define i32 @foo(i1 %z) {
-entry:
-  %a = alloca [10 x i32]
-  %s = alloca [10 x i32]
-  %0 = bitcast [10 x i32]* %a to i8*
-  %1 = bitcast [10 x i32]* %s to i8*
-  call void @llvm.memset.p0i8.i64(i8* nonnull %1, i8 0, i64 40, i32 16, i1 false)
-  %arrayidx = getelementptr inbounds [10 x i32], [10 x i32]* %a, i64 0, i64 0
-  store i32 1, i32* %arrayidx
-  %scevgep = getelementptr [10 x i32], [10 x i32]* %s, i64 0, i64 1
-  %scevgep7 = bitcast i32* %scevgep to i8*
-  br i1 %z, label %for.body3.lr.ph, label %for.inc7.1
-
-for.body3.lr.ph:                                  ; preds = %entry
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %0, i8* %scevgep7, i64 17179869180, i32 4, i1 false)
-  br label %for.inc7.1
-
-for.inc7.1:
-; CHECK: for.inc7.1:
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %0, i8* %scevgep7, i64 4, i32 4, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %0, i8* %scevgep7, i64 4, i32 4, i1 false)
-  %2 = load i32, i32* %arrayidx
-  ret i32 %2
-}
-
-declare void @llvm.memcpy.p0i8.p0i8.i64(i8*, i8*, i64, i32, i1)
-declare void @llvm.memset.p0i8.i64(i8*, i8, i64, i32, i1)
diff --git a/test/Transforms/MemCpyOpt/nonlocal-memcpy-memcpy.ll b/test/Transforms/MemCpyOpt/nonlocal-memcpy-memcpy.ll
deleted file mode 100644
index 5b0510211d9..00000000000
--- a/test/Transforms/MemCpyOpt/nonlocal-memcpy-memcpy.ll
+++ /dev/null
@@ -1,114 +0,0 @@
-; RUN: opt < %s -memcpyopt -S | FileCheck %s
-; Make sure memcpy-memcpy dependence is optimized across
-; basic blocks (conditional branches and invokes).
-
-%struct.s = type { i32, i32 }
-
-@s_foo = private unnamed_addr constant %struct.s { i32 1, i32 2 }, align 4
-@s_baz = private unnamed_addr constant %struct.s { i32 1, i32 2 }, align 4
-@i = external constant i8*
-
-declare void @qux()
-declare void @llvm.memcpy.p0i8.p0i8.i64(i8* nocapture writeonly, i8* nocapture readonly, i64, i32, i1)
-declare void @__cxa_throw(i8*, i8*, i8*)
-declare i32 @__gxx_personality_v0(...)
-declare i8* @__cxa_begin_catch(i8*)
-
-; A simple partial redundancy. Test that the second memcpy is optimized
-; to copy directly from the original source rather than from the temporary.
-
-; CHECK-LABEL: @wobble
-define void @wobble(i8* noalias %dst, i8* %src, i1 %some_condition) {
-bb:
-  %temp = alloca i8, i32 64
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %temp, i8* nonnull %src, i64 64, i32 8, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %temp, i8* nonnull %src, i64 64, i32 8, i1 false)
-  br i1 %some_condition, label %more, label %out
-
-out:
-  call void @qux()
-  unreachable
-
-more:
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %temp, i64 64, i32 8, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %dst, i8* %src, i64 64, i32 8, i1 false)
-  ret void
-}
-
-; A CFG triangle with a partial redundancy targeting an alloca. Test that the
-; memcpy inside the triangle is optimized to copy directly from the original
-; source rather than from the temporary.
-
-; CHECK-LABEL: @foo
-define i32 @foo(i1 %t3) {
-bb:
-  %s = alloca %struct.s, align 4
-  %t = alloca %struct.s, align 4
-  %s1 = bitcast %struct.s* %s to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %s1, i8* bitcast (%struct.s* @s_foo to i8*), i64 8, i32 4, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %s1, i8* bitcast (%struct.s* @s_foo to i8*), i64 8, i32 4, i1 false)
-  br i1 %t3, label %bb4, label %bb7
-
-bb4:                                              ; preds = %bb
-  %t5 = bitcast %struct.s* %t to i8*
-  %s6 = bitcast %struct.s* %s to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %t5, i8* %s6, i64 8, i32 4, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %t5, i8* bitcast (%struct.s* @s_foo to i8*), i64 8, i32 4, i1 false)
-  br label %bb7
-
-bb7:                                              ; preds = %bb4, %bb
-  %t8 = getelementptr %struct.s, %struct.s* %t, i32 0, i32 0
-  %t9 = load i32, i32* %t8, align 4
-  %t10 = getelementptr %struct.s, %struct.s* %t, i32 0, i32 1
-  %t11 = load i32, i32* %t10, align 4
-  %t12 = add i32 %t9, %t11
-  ret i32 %t12
-}
-
-; A CFG diamond with an invoke on one side, and a partially redundant memcpy
-; into an alloca on the other. Test that the memcpy inside the diamond is
-; optimized to copy ; directly from the original source rather than from the
-; temporary. This more complex test represents a relatively common usage
-; pattern.
-
-; CHECK-LABEL: @baz
-define i32 @baz(i1 %t5) personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*) {
-bb:
-  %s = alloca %struct.s, align 4
-  %t = alloca %struct.s, align 4
-  %s3 = bitcast %struct.s* %s to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %s3, i8* bitcast (%struct.s* @s_baz to i8*), i64 8, i32 4, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %s3, i8* bitcast (%struct.s* @s_baz to i8*), i64 8, i32 4, i1 false)
-  br i1 %t5, label %bb6, label %bb22
-
-bb6:                                              ; preds = %bb
-  invoke void @__cxa_throw(i8* null, i8* bitcast (i8** @i to i8*), i8* null)
-          to label %bb25 unwind label %bb9
-
-bb9:                                              ; preds = %bb6
-  %t10 = landingpad { i8*, i32 }
-          catch i8* null
-  br label %bb13
-
-bb13:                                             ; preds = %bb9
-  %t15 = call i8* @__cxa_begin_catch(i8* null)
-  br label %bb23
-
-bb22:                                             ; preds = %bb
-  %t23 = bitcast %struct.s* %t to i8*
-  %s24 = bitcast %struct.s* %s to i8*
-  call void @llvm.memcpy.p0i8.p0i8.i64(i8* %t23, i8* %s24, i64 8, i32 4, i1 false)
-; CHECK: call void @llvm.memcpy.p0i8.p0i8.i64(i8* %t23, i8* bitcast (%struct.s* @s_baz to i8*), i64 8, i32 4, i1 false)
-  br label %bb23
-
-bb23:                                             ; preds = %bb22, %bb13
-  %t17 = getelementptr inbounds %struct.s, %struct.s* %t, i32 0, i32 0
-  %t18 = load i32, i32* %t17, align 4
-  %t19 = getelementptr inbounds %struct.s, %struct.s* %t, i32 0, i32 1
-  %t20 = load i32, i32* %t19, align 4
-  %t21 = add nsw i32 %t18, %t20
-  ret i32 %t21
-
-bb25:                                             ; preds = %bb6
-  unreachable
-}