[llvm] [SDAG] Allow folding stack slots into sincos/frexp in more cases (PR #118117)

[Benjamin Maxwell via llvm-commits]

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@@ -253,3 +253,37 @@ entry:
   store double %cos, ptr %out_cos, align 4
   ret void
 }
+
+declare void @foo(ptr, ptr)
+
+define void @can_fold_with_call_in_chain(float %x, ptr noalias %a, ptr noalias %b) {
+; CHECK-LABEL: can_fold_with_call_in_chain:
+; CHECK:       // %bb.0: // %entry
+; CHECK-NEXT:    str d8, [sp, #-32]! // 8-byte Folded Spill
+; CHECK-NEXT:    str x30, [sp, #8] // 8-byte Folded Spill
+; CHECK-NEXT:    stp x20, x19, [sp, #16] // 16-byte Folded Spill
+; CHECK-NEXT:    .cfi_def_cfa_offset 32
+; CHECK-NEXT:    .cfi_offset w19, -8
+; CHECK-NEXT:    .cfi_offset w20, -16
+; CHECK-NEXT:    .cfi_offset w30, -24
+; CHECK-NEXT:    .cfi_offset b8, -32
+; CHECK-NEXT:    mov x19, x1
+; CHECK-NEXT:    mov x20, x0
+; CHECK-NEXT:    fmov s8, s0
+; CHECK-NEXT:    bl foo
+; CHECK-NEXT:    fmov s0, s8
+; CHECK-NEXT:    mov x0, x20
+; CHECK-NEXT:    mov x1, x19
+; CHECK-NEXT:    bl sincosf
+; CHECK-NEXT:    ldp x20, x19, [sp, #16] // 16-byte Folded Reload
+; CHECK-NEXT:    ldr x30, [sp, #8] // 8-byte Folded Reload
+; CHECK-NEXT:    ldr d8, [sp], #32 // 8-byte Folded Reload
+; CHECK-NEXT:    ret
+entry:
+  %sin = tail call float @llvm.sin.f32(float %x)
+  %cos = tail call float @llvm.cos.f32(float %x)
+  call void @foo(ptr %a, ptr %b)
+  store float %sin, ptr %a, align 4
+  store float %cos, ptr %b, align 4
+  ret void
+}
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MacDue wrote:

The test above (badly named `@f` -- I'll rename it), is the negative test for the issue with folding stores in call sequences. 

https://github.com/llvm/llvm-project/pull/118117