RPCS3/llvm-mirror
1
0
Fork 0
mirror of https://github.com/RPCS3/llvm-mirror.git synced 2025-02-01 05:01:59 +01:00
Code Issues Projects Releases Wiki Activity
llvm-mirror/test/Transforms/InstCombine/fadd.ll
Sanjay Patel 1c95190966 [InstCombine] canonicalize fneg before fmul/fdiv 
Reverse the canonicalization of fneg relative to fmul/fdiv. That makes it
easier to implement the transforms (and possibly other fneg transforms) in
1 place because we can always start the pattern match from fneg (either the
legacy binop or the new unop).

There's a secondary practical benefit seen in PR21914 and PR42681:
https://bugs.llvm.org/show_bug.cgi?id=21914
https://bugs.llvm.org/show_bug.cgi?id=42681
...hoisting fneg rather than sinking seems to play nicer with LICM in IR
(although this change may expose analysis holes in the other direction).

1. The instcombine test changes show the expected neutral IR diffs from
   reversing the order.

2. The reassociation tests show that we were missing an optimization
   opportunity to fold away fneg-of-fneg. My reading of IEEE-754 says
   that all of these transforms are allowed (regardless of binop/unop
   fneg version) because:

   "For all other operations [besides copy/abs/negate/copysign], this
   standard does not specify the sign bit of a NaN result."
   In all of these transforms, we always have some other binop
   (fadd/fsub/fmul/fdiv), so we are free to flip the sign bit of a
   potential intermediate NaN operand.
   (If that interpretation is wrong, then we must already have a bug in
   the existing transforms?)

3. The clang tests shouldn't exist as-is, but that's effectively a
   revert of rL367149 (the test broke with an extension of the
   pre-existing fneg canonicalization in rL367146).

Differential Revision: https://reviews.llvm.org/D65399

llvm-svn: 367447
2019-07-31 16:53:22 +00:00

390 lines
14 KiB
LLVM
Raw Blame History

; NOTE: Assertions have been autogenerated by utils/update_test_checks.py
; RUN: opt < %s -instcombine -S | FileCheck %s
declare void @use(float)
declare void @use_vec(<2 x float>)
; -x + y => y - x
define float @fneg_op0(float %x, float %y) {
; CHECK-LABEL: @fneg_op0(
; CHECK-NEXT: [[ADD:%.*]] = fsub float [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: ret float [[ADD]]
;
%neg = fsub float -0.0, %x
%add = fadd float %neg, %y
ret float %add
}
; x + -y => x - y
define float @fneg_op1(float %x, float %y) {
; CHECK-LABEL: @fneg_op1(
; CHECK-NEXT: [[ADD:%.*]] = fsub float [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: ret float [[ADD]]
;
%neg = fsub float -0.0, %y
%add = fadd float %x, %neg
ret float %add
}
; Z + (-X / Y) --> Z - (X / Y)
define double @fdiv_fneg1(double %x, double %y, double %pz) {
; CHECK-LABEL: @fdiv_fneg1(
; CHECK-NEXT: [[Z:%.*]] = frem double 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fdiv double [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub double [[Z]], [[TMP1]]
; CHECK-NEXT: ret double [[R]]
;
%z = frem double 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub double -0.000000e+00, %x
%div = fdiv double %neg, %y
%r = fadd double %z, %div
ret double %r
}
; Z + (Y / -X) --> Z - (Y / X)
define <2 x double> @fdiv_fneg2(<2 x double> %x, <2 x double> %y, <2 x double> %pz) {
; CHECK-LABEL: @fdiv_fneg2(
; CHECK-NEXT: [[Z:%.*]] = frem <2 x double> <double 4.200000e+01, double 8.000000e+00>, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fdiv <2 x double> [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub <2 x double> [[Z]], [[TMP1]]
; CHECK-NEXT: ret <2 x double> [[R]]
;
%z = frem <2 x double> <double 42.0, double 8.0>, %pz ; thwart complexity-based canonicalization
%neg = fsub <2 x double> <double -0.0, double -0.0>, %x
%div = fdiv <2 x double> %y, %neg
%r = fadd <2 x double> %z, %div
ret <2 x double> %r
}
; Z + (-X * Y) --> Z - (X * Y)
define double @fmul_fneg1(double %x, double %y, double %pz) {
; CHECK-LABEL: @fmul_fneg1(
; CHECK-NEXT: [[Z:%.*]] = frem double 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fmul double [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub double [[Z]], [[TMP1]]
; CHECK-NEXT: ret double [[R]]
;
%z = frem double 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub double -0.000000e+00, %x
%mul = fmul double %neg, %y
%r = fadd double %z, %mul
ret double %r
}
; Z + (Y * -X) --> Z - (Y * X)
define double @fmul_fneg2(double %x, double %py, double %pz) {
; CHECK-LABEL: @fmul_fneg2(
; CHECK-NEXT: [[Y:%.*]] = frem double -4.200000e+01, [[PY:%.*]]
; CHECK-NEXT: [[Z:%.*]] = frem double 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fmul double [[Y]], [[X:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub double [[Z]], [[TMP1]]
; CHECK-NEXT: ret double [[R]]
;
%y = frem double -42.0, %py ; thwart complexity-based canonicalization
%z = frem double 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub double -0.000000e+00, %x
%mul = fmul double %y, %neg
%r = fadd double %z, %mul
ret double %r
}
; (-X / Y) + Z --> Z - (X / Y)
define double @fdiv_fneg1_commute(double %x, double %y, double %pz) {
; CHECK-LABEL: @fdiv_fneg1_commute(
; CHECK-NEXT: [[Z:%.*]] = frem double 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fdiv double [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub double [[Z]], [[TMP1]]
; CHECK-NEXT: ret double [[R]]
;
%z = frem double 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub double -0.000000e+00, %x
%div = fdiv double %neg, %y
%r = fadd double %div, %z
ret double %r
}
; (Y / -X) + Z --> Z - (Y / X)
define <2 x double> @fdiv_fneg2_commute(<2 x double> %x, <2 x double> %y, <2 x double> %pz) {
; CHECK-LABEL: @fdiv_fneg2_commute(
; CHECK-NEXT: [[Z:%.*]] = frem <2 x double> <double 4.200000e+01, double 8.000000e+00>, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fdiv <2 x double> [[Y:%.*]], [[X:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub <2 x double> [[Z]], [[TMP1]]
; CHECK-NEXT: ret <2 x double> [[R]]
;
%z = frem <2 x double> <double 42.0, double 8.0>, %pz ; thwart complexity-based canonicalization
%neg = fsub <2 x double> <double -0.0, double -0.0>, %x
%div = fdiv <2 x double> %y, %neg
%r = fadd <2 x double> %div, %z
ret <2 x double> %r
}
; (-X * Y) + Z --> Z - (X * Y)
define double @fmul_fneg1_commute(double %x, double %y, double %pz) {
; CHECK-LABEL: @fmul_fneg1_commute(
; CHECK-NEXT: [[Z:%.*]] = frem double 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fmul double [[X:%.*]], [[Y:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub double [[Z]], [[TMP1]]
; CHECK-NEXT: ret double [[R]]
;
%z = frem double 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub double -0.000000e+00, %x
%mul = fmul double %neg, %y
%r = fadd double %mul, %z
ret double %r
}
; (Y * -X) + Z --> Z - (Y * X)
define double @fmul_fneg2_commute(double %x, double %py, double %pz) {
; CHECK-LABEL: @fmul_fneg2_commute(
; CHECK-NEXT: [[Y:%.*]] = frem double 4.100000e+01, [[PY:%.*]]
; CHECK-NEXT: [[Z:%.*]] = frem double 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[TMP1:%.*]] = fmul double [[Y]], [[X:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub double [[Z]], [[TMP1]]
; CHECK-NEXT: ret double [[R]]
;
%y = frem double 41.0, %py ; thwart complexity-based canonicalization
%z = frem double 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub double -0.000000e+00, %x
%mul = fmul double %y, %neg
%r = fadd double %mul, %z
ret double %r
}
; Z + (-X / Y) - extra use means we can't transform to fsub without an extra instruction
define float @fdiv_fneg1_extra_use(float %x, float %y, float %pz) {
; CHECK-LABEL: @fdiv_fneg1_extra_use(
; CHECK-NEXT: [[Z:%.*]] = frem float 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[NEG]], [[Y:%.*]]
; CHECK-NEXT: call void @use(float [[DIV]])
; CHECK-NEXT: [[R:%.*]] = fadd float [[Z]], [[DIV]]
; CHECK-NEXT: ret float [[R]]
;
%z = frem float 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub float -0.000000e+00, %x
%div = fdiv float %neg, %y
call void @use(float %div)
%r = fadd float %z, %div
ret float %r
}
; Z + (Y / -X) - extra use means we can't transform to fsub without an extra instruction
define float @fdiv_fneg2_extra_use(float %x, float %py, float %pz) {
; CHECK-LABEL: @fdiv_fneg2_extra_use(
; CHECK-NEXT: [[Y:%.*]] = frem float -4.200000e+01, [[PY:%.*]]
; CHECK-NEXT: [[Z:%.*]] = frem float 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[Y]], [[NEG]]
; CHECK-NEXT: call void @use(float [[DIV]])
; CHECK-NEXT: [[R:%.*]] = fadd float [[Z]], [[DIV]]
; CHECK-NEXT: ret float [[R]]
;
%y = frem float -42.0, %py ; thwart complexity-based canonicalization
%z = frem float 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub float -0.000000e+00, %x
%div = fdiv float %y, %neg
call void @use(float %div)
%r = fadd float %z, %div
ret float %r
}
; Z + (-X * Y) - extra use means we can't transform to fsub without an extra instruction
define <2 x float> @fmul_fneg1_extra_use(<2 x float> %x, <2 x float> %y, <2 x float> %pz) {
; CHECK-LABEL: @fmul_fneg1_extra_use(
; CHECK-NEXT: [[Z:%.*]] = frem <2 x float> <float 4.200000e+01, float -1.000000e+00>, [[PZ:%.*]]
; CHECK-NEXT: [[NEG:%.*]] = fsub <2 x float> <float -0.000000e+00, float -0.000000e+00>, [[X:%.*]]
; CHECK-NEXT: [[MUL:%.*]] = fmul <2 x float> [[NEG]], [[Y:%.*]]
; CHECK-NEXT: call void @use_vec(<2 x float> [[MUL]])
; CHECK-NEXT: [[R:%.*]] = fadd <2 x float> [[Z]], [[MUL]]
; CHECK-NEXT: ret <2 x float> [[R]]
;
%z = frem <2 x float> <float 42.0, float -1.0>, %pz ; thwart complexity-based canonicalization
%neg = fsub <2 x float> <float -0.0, float -0.0>, %x
%mul = fmul <2 x float> %neg, %y
call void @use_vec(<2 x float> %mul)
%r = fadd <2 x float> %z, %mul
ret <2 x float> %r
}
; Z + (Y * -X) - extra use means we can't transform to fsub without an extra instruction
define float @fmul_fneg2_extra_use(float %x, float %py, float %pz) {
; CHECK-LABEL: @fmul_fneg2_extra_use(
; CHECK-NEXT: [[Y:%.*]] = frem float -4.200000e+01, [[PY:%.*]]
; CHECK-NEXT: [[Z:%.*]] = frem float 4.200000e+01, [[PZ:%.*]]
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: [[MUL:%.*]] = fmul float [[Y]], [[NEG]]
; CHECK-NEXT: call void @use(float [[MUL]])
; CHECK-NEXT: [[R:%.*]] = fadd float [[Z]], [[MUL]]
; CHECK-NEXT: ret float [[R]]
;
%y = frem float -42.0, %py ; thwart complexity-based canonicalization
%z = frem float 42.0, %pz ; thwart complexity-based canonicalization
%neg = fsub float -0.000000e+00, %x
%mul = fmul float %y, %neg
call void @use(float %mul)
%r = fadd float %z, %mul
ret float %r
}
; (-X / Y) + Z --> Z - (X / Y)
define float @fdiv_fneg1_extra_use2(float %x, float %y, float %z) {
; CHECK-LABEL: @fdiv_fneg1_extra_use2(
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: call void @use(float [[NEG]])
; CHECK-NEXT: [[TMP1:%.*]] = fdiv float [[X]], [[Y:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub float [[Z:%.*]], [[TMP1]]
; CHECK-NEXT: ret float [[R]]
;
%neg = fsub float -0.000000e+00, %x
call void @use(float %neg)
%div = fdiv float %neg, %y
%r = fadd float %div, %z
ret float %r
}
; (Y / -X) + Z --> Z - (Y / X)
define float @fdiv_fneg2_extra_use2(float %x, float %y, float %z) {
; CHECK-LABEL: @fdiv_fneg2_extra_use2(
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: call void @use(float [[NEG]])
; CHECK-NEXT: [[TMP1:%.*]] = fdiv float [[Y:%.*]], [[X]]
; CHECK-NEXT: [[R:%.*]] = fsub float [[Z:%.*]], [[TMP1]]
; CHECK-NEXT: ret float [[R]]
;
%neg = fsub float -0.000000e+00, %x
call void @use(float %neg)
%div = fdiv float %y, %neg
%r = fadd float %div, %z
ret float %r
}
; (-X * Y) + Z --> Z - (X * Y)
define <2 x float> @fmul_fneg1_extra_use2(<2 x float> %x, <2 x float> %y, <2 x float> %z) {
; CHECK-LABEL: @fmul_fneg1_extra_use2(
; CHECK-NEXT: [[NEG:%.*]] = fsub <2 x float> <float -0.000000e+00, float -0.000000e+00>, [[X:%.*]]
; CHECK-NEXT: call void @use_vec(<2 x float> [[NEG]])
; CHECK-NEXT: [[TMP1:%.*]] = fmul <2 x float> [[X]], [[Y:%.*]]
; CHECK-NEXT: [[R:%.*]] = fsub <2 x float> [[Z:%.*]], [[TMP1]]
; CHECK-NEXT: ret <2 x float> [[R]]
;
%neg = fsub <2 x float> <float -0.0, float -0.0>, %x
call void @use_vec(<2 x float> %neg)
%mul = fmul <2 x float> %neg, %y
%r = fadd <2 x float> %mul, %z
ret <2 x float> %r
}
; (Y * -X) + Z --> Z - (Y * X)
define float @fmul_fneg2_extra_use2(float %x, float %py, float %z) {
; CHECK-LABEL: @fmul_fneg2_extra_use2(
; CHECK-NEXT: [[Y:%.*]] = frem float -4.200000e+01, [[PY:%.*]]
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: call void @use(float [[NEG]])
; CHECK-NEXT: [[TMP1:%.*]] = fmul float [[Y]], [[X]]
; CHECK-NEXT: [[R:%.*]] = fsub float [[Z:%.*]], [[TMP1]]
; CHECK-NEXT: ret float [[R]]
;
%y = frem float -42.0, %py ; thwart complexity-based canonicalization
%neg = fsub float -0.000000e+00, %x
call void @use(float %neg)
%mul = fmul float %y, %neg
%r = fadd float %mul, %z
ret float %r
}
; (-X / Y) + Z --> Z - (X / Y)
define float @fdiv_fneg1_extra_use3(float %x, float %y, float %z) {
; CHECK-LABEL: @fdiv_fneg1_extra_use3(
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: call void @use(float [[NEG]])
; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[NEG]], [[Y:%.*]]
; CHECK-NEXT: call void @use(float [[DIV]])
; CHECK-NEXT: [[R:%.*]] = fadd float [[DIV]], [[Z:%.*]]
; CHECK-NEXT: ret float [[R]]
;
%neg = fsub float -0.000000e+00, %x
call void @use(float %neg)
%div = fdiv float %neg, %y
call void @use(float %div)
%r = fadd float %div, %z
ret float %r
}
; (Y / -X) + Z --> Z - (Y / X)
define float @fdiv_fneg2_extra_use3(float %x, float %y, float %z) {
; CHECK-LABEL: @fdiv_fneg2_extra_use3(
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: call void @use(float [[NEG]])
; CHECK-NEXT: [[DIV:%.*]] = fdiv float [[Y:%.*]], [[NEG]]
; CHECK-NEXT: call void @use(float [[DIV]])
; CHECK-NEXT: [[R:%.*]] = fadd float [[DIV]], [[Z:%.*]]
; CHECK-NEXT: ret float [[R]]
;
%neg = fsub float -0.000000e+00, %x
call void @use(float %neg)
%div = fdiv float %y, %neg
call void @use(float %div)
%r = fadd float %div, %z
ret float %r
}
; (-X * Y) + Z --> Z - (X * Y)
define <2 x float> @fmul_fneg1_extra_use3(<2 x float> %x, <2 x float> %y, <2 x float> %z) {
; CHECK-LABEL: @fmul_fneg1_extra_use3(
; CHECK-NEXT: [[NEG:%.*]] = fsub <2 x float> <float -0.000000e+00, float -0.000000e+00>, [[X:%.*]]
; CHECK-NEXT: call void @use_vec(<2 x float> [[NEG]])
; CHECK-NEXT: [[MUL:%.*]] = fmul <2 x float> [[NEG]], [[Y:%.*]]
; CHECK-NEXT: call void @use_vec(<2 x float> [[MUL]])
; CHECK-NEXT: [[R:%.*]] = fadd <2 x float> [[MUL]], [[Z:%.*]]
; CHECK-NEXT: ret <2 x float> [[R]]
;
%neg = fsub <2 x float> <float -0.0, float -0.0>, %x
call void @use_vec(<2 x float> %neg)
%mul = fmul <2 x float> %neg, %y
call void @use_vec(<2 x float> %mul)
%r = fadd <2 x float> %mul, %z
ret <2 x float> %r
}
; (Y * -X) + Z --> Z - (Y * X)
define float @fmul_fneg2_extra_use3(float %x, float %py, float %z) {
; CHECK-LABEL: @fmul_fneg2_extra_use3(
; CHECK-NEXT: [[Y:%.*]] = frem float -4.200000e+01, [[PY:%.*]]
; CHECK-NEXT: [[NEG:%.*]] = fsub float -0.000000e+00, [[X:%.*]]
; CHECK-NEXT: call void @use(float [[NEG]])
; CHECK-NEXT: [[MUL:%.*]] = fmul float [[Y]], [[NEG]]
; CHECK-NEXT: call void @use(float [[MUL]])
; CHECK-NEXT: [[R:%.*]] = fadd float [[MUL]], [[Z:%.*]]
; CHECK-NEXT: ret float [[R]]
;
%y = frem float -42.0, %py ; thwart complexity-based canonicalization
%neg = fsub float -0.000000e+00, %x
call void @use(float %neg)
%mul = fmul float %y, %neg
call void @use(float %mul)
%r = fadd float %mul, %z
ret float %r
}
Reference in New Issue View Git Blame Copy Permalink