[llvm] [SLP] Let the caller tell canConvertToFMA which operand holds the fmul (PR #218754)

[Dmitry Sidorov via llvm-commits]

================
@@ -10,16 +10,19 @@ define double @fmul_rhs_fadd(ptr %x, ptr %y, ptr %z) {
 ; CHECK-LABEL: define double @fmul_rhs_fadd(
 ; CHECK-SAME: ptr [[X:%.*]], ptr [[Y:%.*]], ptr [[Z:%.*]]) #[[ATTR0:[0-9]+]] {
 ; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[X8:%.*]] = getelementptr inbounds nuw i8, ptr [[X]], i64 8
----------------
MrSidims wrote:

@alexey-bataev please take a look

https://github.com/llvm/llvm-project/pull/218754