[llvm] r283410 - [DAG] add tests to show missing checks for SDNode FMF

[Sanjay Patel via llvm-commits]

Author: spatel
Date: Wed Oct  5 18:20:32 2016
New Revision: 283410

URL: http://llvm.org/viewvc/llvm-project?rev=283410&view=rev
Log:
[DAG] add tests to show missing checks for SDNode FMF

The AVX attribute is added to remove noise caused by SSE's destructive insts.  

Modified:
    llvm/trunk/test/CodeGen/X86/negative-sin.ll

Modified: llvm/trunk/test/CodeGen/X86/negative-sin.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/negative-sin.ll?rev=283410&r1=283409&r2=283410&view=diff
==============================================================================
--- llvm/trunk/test/CodeGen/X86/negative-sin.ll (original)
+++ llvm/trunk/test/CodeGen/X86/negative-sin.ll Wed Oct  5 18:20:32 2016
@@ -1,10 +1,118 @@
 ; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
-; RUN: llc < %s -mtriple=x86_64-unknown-unknown | FileCheck %s
+; RUN: llc < %s -mtriple=x86_64-unknown-unknown -mattr=avx | FileCheck %s
 
 declare double @sin(double %f)
 
-define double @foo(double %e) nounwind #0 {
-; CHECK-LABEL: foo:
+; When the subs are strict, they can't be removed because of signed zero.
+
+define double @strict(double %e) nounwind {
+; CHECK-LABEL: strict:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    pushq %rax
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    callq sin
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    popq %rax
+; CHECK-NEXT:    retq
+;
+  %f = fsub double 0.0, %e
+  %g = call double @sin(double %f) readonly
+  %h = fsub double 0.0, %g
+  ret double %h
+}
+
+; FIXME:
+; 'fast' implies no-signed-zeros, so the negates fold away.
+; The 'sin' does not need any fast-math-flags for this transform.
+
+define double @fast(double %e) nounwind {
+; CHECK-LABEL: fast:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    pushq %rax
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    callq sin
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    popq %rax
+; CHECK-NEXT:    retq
+;
+  %f = fsub fast double 0.0, %e
+  %g = call double @sin(double %f) readonly
+  %h = fsub fast double 0.0, %g
+  ret double %h
+}
+
+; FIXME:
+; No-signed-zeros is all that we need for this transform.
+
+define double @nsz(double %e) nounwind {
+; CHECK-LABEL: nsz:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    pushq %rax
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    callq sin
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    popq %rax
+; CHECK-NEXT:    retq
+;
+  %f = fsub nsz double 0.0, %e
+  %g = call double @sin(double %f) readonly
+  %h = fsub nsz double 0.0, %g
+  ret double %h
+}
+
+; FIXME:
+; The 1st negate is strict, so we can't kill that sub, but the 2nd disappears.
+
+define double @semi_strict1(double %e) nounwind {
+; CHECK-LABEL: semi_strict1:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    pushq %rax
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    callq sin
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    popq %rax
+; CHECK-NEXT:    retq
+;
+  %f = fsub double 0.0, %e
+  %g = call double @sin(double %f) readonly
+  %h = fsub nsz double 0.0, %g
+  ret double %h
+}
+
+; FIXME:
+; The 2nd negate is strict, so we can't kill it. It becomes an add of zero instead.
+
+define double @semi_strict2(double %e) nounwind {
+; CHECK-LABEL: semi_strict2:
+; CHECK:       # BB#0:
+; CHECK-NEXT:    pushq %rax
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    callq sin
+; CHECK-NEXT:    vxorpd %xmm1, %xmm1, %xmm1
+; CHECK-NEXT:    vsubsd %xmm0, %xmm1, %xmm0
+; CHECK-NEXT:    popq %rax
+; CHECK-NEXT:    retq
+;
+  %f = fsub nsz double 0.0, %e
+  %g = call double @sin(double %f) readonly
+  %h = fsub double 0.0, %g
+  ret double %h
+}
+
+; FIXME:
+; Auto-upgrade function attribute to IR-level fast-math-flags.
+
+define double @fn_attr(double %e) nounwind #0 {
+; CHECK-LABEL: fn_attr:
 ; CHECK:       # BB#0:
 ; CHECK-NEXT:    jmp sin
 ;
@@ -14,6 +122,5 @@ define double @foo(double %e) nounwind #
   ret double %h
 }
 
-; FIXME: Check the instruction/node-level FMF instead of a function-level attribute.
 attributes #0 = { "unsafe-fp-math"="true" }