Revert r314886 "[X86] Improvement in CodeGen instruction selection for LEAs (re-applying post required revision changes.)"

It broke the Chromium / SQLite build; see PR34830.

> Summary:
>    1/  Operand folding during complex pattern matching for LEAs has been
>        extended, such that it promotes Scale to accommodate similar operand
>        appearing in the DAG.
>        e.g.
>          T1 = A + B
>          T2 = T1 + 10
>          T3 = T2 + A
>        For above DAG rooted at T3, X86AddressMode will no look like
>          Base = B , Index = A , Scale = 2 , Disp = 10
>
>    2/  During OptimizeLEAPass down the pipeline factorization is now performed over LEAs
>        so that if there is an opportunity then complex LEAs (having 3 operands)
>        could be factored out.
>        e.g.
>          leal 1(%rax,%rcx,1), %rdx
>          leal 1(%rax,%rcx,2), %rcx
>        will be factored as following
>          leal 1(%rax,%rcx,1), %rdx
>          leal (%rdx,%rcx)   , %edx
>
>    3/ Aggressive operand folding for AM based selection for LEAs is sensitive to loops,
>       thus avoiding creation of any complex LEAs within a loop.
>
> Reviewers: lsaba, RKSimon, craig.topper, qcolombet, jmolloy
>
> Reviewed By: lsaba
>
> Subscribers: jmolloy, spatel, igorb, llvm-commits
>
>     Differential Revision: https://reviews.llvm.org/D35014

llvm-svn: 314919

1 files changed, 11 insertions, 3 deletions

diff --git a/llvm/test/CodeGen/X86/lea-opt-cse1.ll b/llvm/test/CodeGen/X86/lea-opt-cse1.ll
index 857a23f0f8f..86218a67d84 100644
--- a/llvm/test/CodeGen/X86/lea-opt-cse1.ll
+++ b/llvm/test/CodeGen/X86/lea-opt-cse1.ll
@@ -9,21 +9,29 @@ define void @test_func(%struct.SA* nocapture %ctx, i32 %n) local_unnamed_addr {
 ; X64:       # BB#0: # %entry
 ; X64-NEXT:    movl (%rdi), %eax
 ; X64-NEXT:    movl 16(%rdi), %ecx
+; X64-NEXT:    leal (%rax,%rcx), %edx
 ; X64-NEXT:    leal 1(%rax,%rcx), %eax
 ; X64-NEXT:    movl %eax, 12(%rdi)
-; X64-NEXT:    addq %rcx, %eax
+; X64-NEXT:    leal 1(%rcx,%rdx), %eax
 ; X64-NEXT:    movl %eax, 16(%rdi)
 ; X64-NEXT:    retq
 ;
 ; X86-LABEL: test_func:
 ; X86:       # BB#0: # %entry
+; X86-NEXT:    pushl %esi
+; X86-NEXT:  .Lcfi0:
+; X86-NEXT:    .cfi_def_cfa_offset 8
+; X86-NEXT:  .Lcfi1:
+; X86-NEXT:    .cfi_offset %esi, -8
 ; X86-NEXT:    movl {{[0-9]+}}(%esp), %eax
 ; X86-NEXT:    movl (%eax), %ecx
 ; X86-NEXT:    movl 16(%eax), %edx
-; X86-NEXT:    leal 1(%ecx,%edx), %ecx
-; X86-NEXT:    movl %ecx, 12(%eax)
+; X86-NEXT:    leal 1(%ecx,%edx), %esi
 ; X86-NEXT:    addl %edx, %ecx
+; X86-NEXT:    movl %esi, 12(%eax)
+; X86-NEXT:    leal 1(%edx,%ecx), %ecx
 ; X86-NEXT:    movl %ecx, 16(%eax)
+; X86-NEXT:    popl %esi
 ; X86-NEXT:    retl
  entry:
    %h0 = getelementptr inbounds %struct.SA, %struct.SA* %ctx, i64 0, i32 0