[AArch64] Check fmul node single use in fused multiply patterns
Check for single use of fmul node in fused multiply patterns
to allow generation of fused multiply add/sub instructions.
Otherwise fmul operation ends up being repeated more than
once which does not help peformance on targets with
only one MAC unit, as for example cortex-a53.
llvm-svn: 197929
diff --git a/llvm/test/CodeGen/AArch64/fp-dp3.ll b/llvm/test/CodeGen/AArch64/fp-dp3.ll
index 6b9acc8..2a6790e 100644
--- a/llvm/test/CodeGen/AArch64/fp-dp3.ll
+++ b/llvm/test/CodeGen/AArch64/fp-dp3.ll
@@ -135,3 +135,29 @@
ret float %sum
}
+; Another set of tests that check for multiply single use
+
+define float @test_fmadd_unfused_su(float %a, float %b, float %c) {
+; CHECK-LABEL: test_fmadd_unfused_su:
+ %prod = fmul float %b, %c
+ %sum = fadd float %a, %prod
+ %res = fadd float %sum, %prod
+; CHECK-NOT: fmadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK: fmul {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK: fadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK: fadd {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+ ret float %res
+}
+
+define float @test_fmsub_unfused_su(float %a, float %b, float %c) {
+; CHECK-LABEL: test_fmsub_unfused_su:
+ %prod = fmul float %b, %c
+ %diff = fsub float %a, %prod
+ %res = fsub float %diff, %prod
+; CHECK-NOT: fmsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK: fmul {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK: fsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+; CHECK: fsub {{s[0-9]+}}, {{s[0-9]+}}, {{s[0-9]+}}
+ ret float %res
+}
+