[X86] Special-case 2x CMOV when custom-inserting.

This lets us avoid a few copies that are otherwise hard to get rid of.
The way this is done is, the custom-inserter looks at the following
instruction for another CMOV, and replaces both at the same time.
A previous version used a new CMOV2 opcode, but the custom inserter
is expected to be able to return a different basic block anyway, which
means it's OK - though far from ideal - to alter that block's contents.
Explicitly document that, in case it ever makes a difference.
Alternatives welcome!

Follow-up to r231045.

rdar://19767934
Closes http://reviews.llvm.org/D8019

llvm-svn: 231046

1 files changed, 71 insertions, 109 deletions

diff --git a/llvm/test/CodeGen/X86/cmovcmov.ll b/llvm/test/CodeGen/X86/cmovcmov.ll
index e9ac86f4108..982bc82c4c7 100644
--- a/llvm/test/CodeGen/X86/cmovcmov.ll
+++ b/llvm/test/CodeGen/X86/cmovcmov.ll
@@ -15,21 +15,18 @@ target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
 ; CMOV-NEXT: movl  %edi, %eax
 ; CMOV-NEXT: retq
 
-; NOCMOV-NEXT:   flds  8(%esp)
-; NOCMOV-NEXT:   flds  4(%esp)
-; NOCMOV-NEXT:   fucompp
-; NOCMOV-NEXT:   fnstsw  %ax
-; NOCMOV-NEXT:   sahf
-; NOCMOV-NEXT:   leal  16(%esp), %eax
-; NOCMOV-NEXT:   movl  %eax, %ecx
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  12(%esp), %ecx
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %ecx, %eax
-; NOCMOV-NEXT: [[TBB2]]:
-; NOCMOV-NEXT:   movl  (%eax), %eax
-; NOCMOV-NEXT:   retl
+; NOCMOV-NEXT:  flds  8(%esp)
+; NOCMOV-NEXT:  flds  4(%esp)
+; NOCMOV-NEXT:  fucompp
+; NOCMOV-NEXT:  fnstsw  %ax
+; NOCMOV-NEXT:  sahf
+; NOCMOV-NEXT:  leal  16(%esp), %eax
+; NOCMOV-NEXT:  jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:  jp  [[TBB]]
+; NOCMOV-NEXT:  leal  12(%esp), %eax
+; NOCMOV-NEXT:[[TBB]]:
+; NOCMOV-NEXT:  movl  (%eax), %eax
+; NOCMOV-NEXT:  retl
 define i32 @test_select_fcmp_oeq_i32(float %a, float %b, i32 %c, i32 %d) #0 {
 entry:
   %cmp = fcmp oeq float %a, %b
@@ -51,13 +48,10 @@ entry:
 ; NOCMOV-NEXT:   fnstsw  %ax
 ; NOCMOV-NEXT:   sahf
 ; NOCMOV-NEXT:   leal  20(%esp), %ecx
-; NOCMOV-NEXT:   movl  %ecx, %eax
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  12(%esp), %eax
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %eax, %ecx
-; NOCMOV-NEXT: [[TBB2]]:
+; NOCMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:   jp  [[TBB]]
+; NOCMOV-NEXT:   leal  12(%esp), %ecx
+; NOCMOV-NEXT: [[TBB]]:
 ; NOCMOV-NEXT:   movl  (%ecx), %eax
 ; NOCMOV-NEXT:   orl  $4, %ecx
 ; NOCMOV-NEXT:   movl  (%ecx), %edx
@@ -83,13 +77,10 @@ entry:
 ; NOCMOV-NEXT:   fnstsw  %ax
 ; NOCMOV-NEXT:   sahf
 ; NOCMOV-NEXT:   leal  12(%esp), %ecx
-; NOCMOV-NEXT:   movl  %ecx, %eax
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  20(%esp), %eax
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %eax, %ecx
-; NOCMOV-NEXT: [[TBB2]]:
+; NOCMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:   jp  [[TBB]]
+; NOCMOV-NEXT:   leal  20(%esp), %ecx
+; NOCMOV-NEXT: [[TBB]]:
 ; NOCMOV-NEXT:   movl  (%ecx), %eax
 ; NOCMOV-NEXT:   orl  $4, %ecx
 ; NOCMOV-NEXT:   movl  (%ecx), %edx
@@ -104,13 +95,10 @@ entry:
 ; CHECK-LABEL: test_select_fcmp_oeq_f64:
 
 ; CMOV-NEXT:   ucomiss  %xmm1, %xmm0
-; CMOV-NEXT:   movaps  %xmm3, %xmm0
-; CMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; CMOV-NEXT:   movaps  %xmm2, %xmm0
-; CMOV-NEXT: [[TBB1]]:
-; CMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; CMOV-NEXT:   movaps  %xmm0, %xmm3
-; CMOV-NEXT: [[TBB2]]:
+; CMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; CMOV-NEXT:   jp  [[TBB]]
+; CMOV-NEXT:   movaps  %xmm2, %xmm3
+; CMOV-NEXT: [[TBB]]:
 ; CMOV-NEXT:   movaps  %xmm3, %xmm0
 ; CMOV-NEXT:   retq
 
@@ -120,13 +108,10 @@ entry:
 ; NOCMOV-NEXT:   fnstsw  %ax
 ; NOCMOV-NEXT:   sahf
 ; NOCMOV-NEXT:   leal  20(%esp), %eax
-; NOCMOV-NEXT:   movl  %eax, %ecx
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  12(%esp), %ecx
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %ecx, %eax
-; NOCMOV-NEXT: [[TBB2]]:
+; NOCMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:   jp  [[TBB]]
+; NOCMOV-NEXT:   leal  12(%esp), %eax
+; NOCMOV-NEXT: [[TBB]]:
 ; NOCMOV-NEXT:   fldl  (%eax)
 ; NOCMOV-NEXT:   retl
 define double @test_select_fcmp_oeq_f64(float %a, float %b, double %c, double %d) #0 {
@@ -139,68 +124,51 @@ entry:
 ; CHECK-LABEL: test_select_fcmp_oeq_v4i32:
 
 ; CMOV-NEXT:   ucomiss  %xmm1, %xmm0
-; CMOV-NEXT:   movaps  %xmm3, %xmm0
-; CMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; CMOV-NEXT:   movaps  %xmm2, %xmm0
-; CMOV-NEXT: [[TBB1]]:
-; CMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; CMOV-NEXT:   movaps  %xmm0, %xmm3
-; CMOV-NEXT: [[TBB2]]:
+; CMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; CMOV-NEXT:   jp  [[TBB]]
+; CMOV-NEXT:   movaps  %xmm2, %xmm3
+; CMOV-NEXT: [[TBB]]:
 ; CMOV-NEXT:   movaps  %xmm3, %xmm0
 ; CMOV-NEXT:   retq
 
-; NOCMOV-NEXT:   pushl  %ebx
 ; NOCMOV-NEXT:   pushl  %edi
 ; NOCMOV-NEXT:   pushl  %esi
-; NOCMOV-NEXT:   flds  24(%esp)
 ; NOCMOV-NEXT:   flds  20(%esp)
+; NOCMOV-NEXT:   flds  16(%esp)
 ; NOCMOV-NEXT:   fucompp
 ; NOCMOV-NEXT:   fnstsw  %ax
 ; NOCMOV-NEXT:   sahf
-; NOCMOV-NEXT:   leal  44(%esp), %eax
-; NOCMOV-NEXT:   movl  %eax, %ecx
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  28(%esp), %ecx
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %ecx, %eax
-; NOCMOV-NEXT: [[TBB2]]:
+; NOCMOV-NEXT:   leal  40(%esp), %eax
+; NOCMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:   jp  [[TBB]]
+; NOCMOV-NEXT:   leal  24(%esp), %eax
+; NOCMOV-NEXT: [[TBB]]:
 ; NOCMOV-NEXT:   movl  (%eax), %eax
-; NOCMOV-NEXT:   leal  48(%esp), %ecx
-; NOCMOV-NEXT:   movl  %ecx, %edx
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  32(%esp), %edx
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %edx, %ecx
-; NOCMOV-NEXT: [[TBB2]]:
+; NOCMOV-NEXT:   leal  44(%esp), %ecx
+; NOCMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:   jp  [[TBB]]
+; NOCMOV-NEXT:   leal  28(%esp), %ecx
+; NOCMOV-NEXT: [[TBB]]:
 ; NOCMOV-NEXT:   movl  (%ecx), %ecx
-; NOCMOV-NEXT:   leal  52(%esp), %edx
-; NOCMOV-NEXT:   movl  %edx, %esi
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  36(%esp), %esi
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %esi, %edx
-; NOCMOV-NEXT: [[TBB2]]:
-; NOCMOV-NEXT:   movl  (%edx), %edx
-; NOCMOV-NEXT:   leal  56(%esp), %esi
-; NOCMOV-NEXT:   movl  %esi, %ebx
-; NOCMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   leal  40(%esp), %ebx
-; NOCMOV-NEXT: [[TBB1]]:
-; NOCMOV-NEXT:   movl  16(%esp), %edi
-; NOCMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; NOCMOV-NEXT:   movl  %ebx, %esi
-; NOCMOV-NEXT: [[TBB2]]:
+; NOCMOV-NEXT:   leal  48(%esp), %esi
+; NOCMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:   jp  [[TBB]]
+; NOCMOV-NEXT:   leal  32(%esp), %esi
+; NOCMOV-NEXT: [[TBB]]:
+; NOCMOV-NEXT:   movl  12(%esp), %edx
 ; NOCMOV-NEXT:   movl  (%esi), %esi
-; NOCMOV-NEXT:   movl  %esi, 12(%edi)
-; NOCMOV-NEXT:   movl  %edx, 8(%edi)
-; NOCMOV-NEXT:   movl  %ecx, 4(%edi)
-; NOCMOV-NEXT:   movl  %eax, (%edi)
+; NOCMOV-NEXT:   leal  52(%esp), %edi
+; NOCMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; NOCMOV-NEXT:   jp  [[TBB]]
+; NOCMOV-NEXT:   leal  36(%esp), %edi
+; NOCMOV-NEXT: [[TBB]]:
+; NOCMOV-NEXT:   movl  (%edi), %edi
+; NOCMOV-NEXT:   movl  %edi, 12(%edx)
+; NOCMOV-NEXT:   movl  %esi, 8(%edx)
+; NOCMOV-NEXT:   movl  %ecx, 4(%edx)
+; NOCMOV-NEXT:   movl  %eax, (%edx)
 ; NOCMOV-NEXT:   popl  %esi
 ; NOCMOV-NEXT:   popl  %edi
-; NOCMOV-NEXT:   popl  %ebx
 ; NOCMOV-NEXT:   retl  $4
 define <4 x i32> @test_select_fcmp_oeq_v4i32(float %a, float %b, <4 x i32> %c, <4 x i32> %d) #0 {
 entry:
@@ -217,17 +185,14 @@ entry:
 ; CHECK-LABEL: test_zext_fcmp_une:
 ; CMOV-NEXT:   ucomiss  %xmm1, %xmm0
 ; CMOV-NEXT:   movss  [[ONE_F32_LCPI]](%rip), %xmm0
-; CMOV-NEXT:   movaps  %xmm0, %xmm1
-; CMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; CMOV-NEXT:   xorps  %xmm1, %xmm1
-; CMOV-NEXT: [[TBB1]]:
-; CMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; CMOV-NEXT:   movaps  %xmm1, %xmm0
-; CMOV-NEXT: [[TBB2]]:
+; CMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; CMOV-NEXT:   jp  [[TBB]]
+; CMOV-NEXT:   xorps  %xmm0, %xmm0
+; CMOV-NEXT: [[TBB]]:
 ; CMOV-NEXT:   retq
 
-; NOCMOV:     jne
-; NOCMOV:     jp
+; NOCMOV:        jne
+; NOCMOV-NEXT:   jp
 define float @test_zext_fcmp_une(float %a, float %b) #0 {
 entry:
   %cmp = fcmp une float %a, %b
@@ -242,17 +207,14 @@ entry:
 ; CHECK-LABEL: test_zext_fcmp_oeq:
 ; CMOV-NEXT:   ucomiss  %xmm1, %xmm0
 ; CMOV-NEXT:   xorps  %xmm0, %xmm0
-; CMOV-NEXT:   xorps  %xmm1, %xmm1
-; CMOV-NEXT:   jne  [[TBB1:.LBB[0-9_]+]]
-; CMOV-NEXT:   movss  [[ONE_F32_LCPI]](%rip), %xmm1
-; CMOV-NEXT: [[TBB1]]:
-; CMOV-NEXT:   jp  [[TBB2:.LBB[0-9_]+]]
-; CMOV-NEXT:   movaps  %xmm1, %xmm0
-; CMOV-NEXT: [[TBB2]]:
+; CMOV-NEXT:   jne  [[TBB:.LBB[0-9_]+]]
+; CMOV-NEXT:   jp  [[TBB]]
+; CMOV-NEXT:   movss  [[ONE_F32_LCPI]](%rip), %xmm0
+; CMOV-NEXT: [[TBB]]:
 ; CMOV-NEXT:   retq
 
-; NOCMOV:   jne
-; NOCMOV:   jp
+; NOCMOV:        jne
+; NOCMOV-NEXT:   jp
 define float @test_zext_fcmp_oeq(float %a, float %b) #0 {
 entry:
   %cmp = fcmp oeq float %a, %b