[NFC][Test] Add a PowerPC test to verify the behavior of a*b +/- c*d

diff --git a/llvm/test/CodeGen/PowerPC/fma-precision.ll b/llvm/test/CodeGen/PowerPC/fma-precision.ll
new file mode 100644 (file)
index 0000000..24c304d
--- /dev/null
+++ b/llvm/test/CodeGen/PowerPC/fma-precision.ll
@@ -0,0 +1,99 @@
+; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py
+; RUN: llc < %s -verify-machineinstrs -mcpu=pwr9 -mtriple=powerpc64le-linux-gnu | FileCheck %s
+
+; Verify that the fold of a*b-c*d respect the uses of a*b
+define double @fsub1(double %a, double %b, double %c, double %d)  {
+; CHECK-LABEL: fsub1:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xsmuldp 3, 4, 3
+; CHECK-NEXT:    xsmuldp 0, 2, 1
+; CHECK-NEXT:    xsmsubadp 3, 2, 1
+; CHECK-NEXT:    xsmuldp 1, 0, 3
+; CHECK-NEXT:    blr
+entry:
+  %mul = fmul fast double %b, %a
+  %mul1 = fmul fast double %d, %c
+  %sub = fsub fast double %mul, %mul1
+  %mul3 = fmul fast double %mul, %sub
+  ret double %mul3
+}
+
+; Verify that the fold of a*b-c*d respect the uses of c*d
+define double @fsub2(double %a, double %b, double %c, double %d)  {
+; CHECK-LABEL: fsub2:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xsmuldp 0, 4, 3
+; CHECK-NEXT:    fmr 3, 0
+; CHECK-NEXT:    xsmsubadp 3, 2, 1
+; CHECK-NEXT:    xsmuldp 1, 0, 3
+; CHECK-NEXT:    blr
+entry:
+  %mul = fmul fast double %b, %a
+  %mul1 = fmul fast double %d, %c
+  %sub = fsub fast double %mul, %mul1
+  %mul3 = fmul fast double %mul1, %sub
+  ret double %mul3
+}
+
+; Verify that the fold of a*b-c*d if there is no uses of a*b and c*d
+define double @fsub3(double %a, double %b, double %c, double %d)  {
+; CHECK-LABEL: fsub3:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xsmuldp 0, 4, 3
+; CHECK-NEXT:    xsmsubadp 0, 2, 1
+; CHECK-NEXT:    fmr 1, 0
+; CHECK-NEXT:    blr
+entry:
+  %mul = fmul fast double %b, %a
+  %mul1 = fmul fast double %d, %c
+  %sub = fsub fast double %mul, %mul1
+  ret double %sub
+}
+
+; Verify that the fold of a*b+c*d respect the uses of a*b
+define double @fadd1(double %a, double %b, double %c, double %d)  {
+; CHECK-LABEL: fadd1:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xsmuldp 0, 2, 1
+; CHECK-NEXT:    fmr 1, 0
+; CHECK-NEXT:    xsmaddadp 1, 4, 3
+; CHECK-NEXT:    xsmuldp 1, 0, 1
+; CHECK-NEXT:    blr
+entry:
+  %mul = fmul fast double %b, %a
+  %mul1 = fmul fast double %d, %c
+  %add = fadd fast double %mul1, %mul
+  %mul3 = fmul fast double %mul, %add
+  ret double %mul3
+}
+
+; Verify that the fold of a*b+c*d respect the uses of c*d
+define double @fadd2(double %a, double %b, double %c, double %d)  {
+; CHECK-LABEL: fadd2:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xsmuldp 0, 4, 3
+; CHECK-NEXT:    fmr 3, 0
+; CHECK-NEXT:    xsmaddadp 3, 2, 1
+; CHECK-NEXT:    xsmuldp 1, 0, 3
+; CHECK-NEXT:    blr
+entry:
+  %mul = fmul fast double %b, %a
+  %mul1 = fmul fast double %d, %c
+  %add = fadd fast double %mul1, %mul
+  %mul3 = fmul fast double %mul1, %add
+  ret double %mul3
+}
+
+; Verify that the fold of a*b+c*d if there is no uses of a*b and c*d
+define double @fadd3(double %a, double %b, double %c, double %d)  {
+; CHECK-LABEL: fadd3:
+; CHECK:       # %bb.0: # %entry
+; CHECK-NEXT:    xsmuldp 1, 2, 1
+; CHECK-NEXT:    xsmaddadp 1, 4, 3
+; CHECK-NEXT:    blr
+entry:
+  %mul = fmul fast double %b, %a
+  %mul1 = fmul fast double %d, %c
+  %add = fadd fast double %mul1, %mul
+  ret double %add
+}