[SelectionDAG] Add SimplifyDemandedBits to SimplifyDemandedVectorElts simplification

This patch enables SimplifyDemandedBits to call SimplifyDemandedVectorElts in cases where the demanded bits mask covers entire elements of a bitcasted source vector.

There are a couple of cases here where simplification at a deeper level (such as through bitcasts) prevents further simplification - CommitTargetLoweringOpt only adds immediate uses/users back to the worklist when we might want to combine the original caller again to see what else it can simplify.

As well as that I had to disable handling of bool vector until SimplifyDemandedVectorElts better supports some of their opcodes (SETCC, shifts etc.).

Fixes PR39178

Differential Revision: https://reviews.llvm.org/D52935

llvm-svn: 343913
diff --git a/llvm/test/CodeGen/X86/combine-pmuldq.ll b/llvm/test/CodeGen/X86/combine-pmuldq.ll
index 65c6ae5..3bdd5a3 100644
--- a/llvm/test/CodeGen/X86/combine-pmuldq.ll
+++ b/llvm/test/CodeGen/X86/combine-pmuldq.ll
@@ -41,20 +41,15 @@
   ret <2 x i64> %5
 }
 
-; TODO - blends are superfluous
 define <2 x i64> @combine_shuffle_zero_pmuludq(<4 x i32> %a0, <4 x i32> %a1) {
 ; SSE-LABEL: combine_shuffle_zero_pmuludq:
 ; SSE:       # %bb.0:
-; SSE-NEXT:    pxor %xmm2, %xmm2
-; SSE-NEXT:    pblendw {{.*#+}} xmm0 = xmm0[0,1],xmm2[2,3],xmm0[4,5],xmm2[6,7]
-; SSE-NEXT:    pblendw {{.*#+}} xmm1 = xmm1[0,1],xmm2[2,3],xmm1[4,5],xmm2[6,7]
 ; SSE-NEXT:    pmuludq %xmm1, %xmm0
 ; SSE-NEXT:    retq
 ;
 ; AVX2-LABEL: combine_shuffle_zero_pmuludq:
 ; AVX2:       # %bb.0:
 ; AVX2-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX2-NEXT:    vpblendd {{.*#+}} xmm0 = xmm0[0],xmm2[1],xmm0[2],xmm2[3]
 ; AVX2-NEXT:    vpblendd {{.*#+}} xmm1 = xmm1[0],xmm2[1],xmm1[2],xmm2[3]
 ; AVX2-NEXT:    vpmuludq %xmm1, %xmm0, %xmm0
 ; AVX2-NEXT:    retq
@@ -62,7 +57,6 @@
 ; AVX512VL-LABEL: combine_shuffle_zero_pmuludq:
 ; AVX512VL:       # %bb.0:
 ; AVX512VL-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX512VL-NEXT:    vpblendd {{.*#+}} xmm0 = xmm0[0],xmm2[1],xmm0[2],xmm2[3]
 ; AVX512VL-NEXT:    vpblendd {{.*#+}} xmm1 = xmm1[0],xmm2[1],xmm1[2],xmm2[3]
 ; AVX512VL-NEXT:    vpmuludq %xmm1, %xmm0, %xmm0
 ; AVX512VL-NEXT:    retq
@@ -70,7 +64,6 @@
 ; AVX512DQVL-LABEL: combine_shuffle_zero_pmuludq:
 ; AVX512DQVL:       # %bb.0:
 ; AVX512DQVL-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX512DQVL-NEXT:    vpblendd {{.*#+}} xmm0 = xmm0[0],xmm2[1],xmm0[2],xmm2[3]
 ; AVX512DQVL-NEXT:    vpblendd {{.*#+}} xmm1 = xmm1[0],xmm2[1],xmm1[2],xmm2[3]
 ; AVX512DQVL-NEXT:    vpmuludq %xmm1, %xmm0, %xmm0
 ; AVX512DQVL-NEXT:    retq
@@ -82,23 +75,16 @@
   ret <2 x i64> %5
 }
 
-; TODO - blends are superfluous
 define <4 x i64> @combine_shuffle_zero_pmuludq_256(<8 x i32> %a0, <8 x i32> %a1) {
 ; SSE-LABEL: combine_shuffle_zero_pmuludq_256:
 ; SSE:       # %bb.0:
-; SSE-NEXT:    pxor %xmm4, %xmm4
-; SSE-NEXT:    pblendw {{.*#+}} xmm1 = xmm1[0,1],xmm4[2,3],xmm1[4,5],xmm4[6,7]
-; SSE-NEXT:    pblendw {{.*#+}} xmm0 = xmm0[0,1],xmm4[2,3],xmm0[4,5],xmm4[6,7]
-; SSE-NEXT:    pblendw {{.*#+}} xmm3 = xmm3[0,1],xmm4[2,3],xmm3[4,5],xmm4[6,7]
-; SSE-NEXT:    pmuludq %xmm3, %xmm1
-; SSE-NEXT:    pblendw {{.*#+}} xmm2 = xmm2[0,1],xmm4[2,3],xmm2[4,5],xmm4[6,7]
 ; SSE-NEXT:    pmuludq %xmm2, %xmm0
+; SSE-NEXT:    pmuludq %xmm3, %xmm1
 ; SSE-NEXT:    retq
 ;
 ; AVX2-LABEL: combine_shuffle_zero_pmuludq_256:
 ; AVX2:       # %bb.0:
 ; AVX2-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX2-NEXT:    vpblendd {{.*#+}} ymm0 = ymm0[0],ymm2[1],ymm0[2],ymm2[3],ymm0[4],ymm2[5],ymm0[6],ymm2[7]
 ; AVX2-NEXT:    vpblendd {{.*#+}} ymm1 = ymm1[0],ymm2[1],ymm1[2],ymm2[3],ymm1[4],ymm2[5],ymm1[6],ymm2[7]
 ; AVX2-NEXT:    vpmuludq %ymm1, %ymm0, %ymm0
 ; AVX2-NEXT:    retq
@@ -106,7 +92,6 @@
 ; AVX512VL-LABEL: combine_shuffle_zero_pmuludq_256:
 ; AVX512VL:       # %bb.0:
 ; AVX512VL-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX512VL-NEXT:    vpblendd {{.*#+}} ymm0 = ymm0[0],ymm2[1],ymm0[2],ymm2[3],ymm0[4],ymm2[5],ymm0[6],ymm2[7]
 ; AVX512VL-NEXT:    vpblendd {{.*#+}} ymm1 = ymm1[0],ymm2[1],ymm1[2],ymm2[3],ymm1[4],ymm2[5],ymm1[6],ymm2[7]
 ; AVX512VL-NEXT:    vpmuludq %ymm1, %ymm0, %ymm0
 ; AVX512VL-NEXT:    retq
@@ -114,7 +99,6 @@
 ; AVX512DQVL-LABEL: combine_shuffle_zero_pmuludq_256:
 ; AVX512DQVL:       # %bb.0:
 ; AVX512DQVL-NEXT:    vpxor %xmm2, %xmm2, %xmm2
-; AVX512DQVL-NEXT:    vpblendd {{.*#+}} ymm0 = ymm0[0],ymm2[1],ymm0[2],ymm2[3],ymm0[4],ymm2[5],ymm0[6],ymm2[7]
 ; AVX512DQVL-NEXT:    vpblendd {{.*#+}} ymm1 = ymm1[0],ymm2[1],ymm1[2],ymm2[3],ymm1[4],ymm2[5],ymm1[6],ymm2[7]
 ; AVX512DQVL-NEXT:    vpmuludq %ymm1, %ymm0, %ymm0
 ; AVX512DQVL-NEXT:    retq