diff options
| author | Paul E. Murphy <murp@ibm.com> | 2024-03-29 16:11:36 -0500 |
|---|---|---|
| committer | Paul Murphy <murp@ibm.com> | 2024-04-04 15:24:29 +0000 |
| commit | ebf7747dbe0204a930815200b3cbc63a09967bf9 (patch) | |
| tree | 5060f3725293c5ff138926d105d058866584b09b /src/cmd/internal | |
| parent | 0f10ffec13a1eecb2b18e0b9d75773faf42e7ebd (diff) | |
| download | go-ebf7747dbe0204a930815200b3cbc63a09967bf9.tar.xz | |
cmd/internal/obj/ppc64: on Power10, use xxspltidp for float constants
Any normal float32 constant can be generated by this instruction;
use xxspltidp when possible. This prefixed instruction is much
faster than the two instruction load sequence from the
float32/float64 constant pool.
Change-Id: Id751d9ffdae71463adbde66427b986f0b2ef74c2
Reviewed-on: https://go-review.googlesource.com/c/go/+/575555
Reviewed-by: Than McIntosh <thanm@google.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Paul Murphy <murp@ibm.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Diffstat (limited to 'src/cmd/internal')
| -rw-r--r-- | src/cmd/internal/obj/ppc64/obj9.go | 28 |
1 files changed, 26 insertions, 2 deletions
diff --git a/src/cmd/internal/obj/ppc64/obj9.go b/src/cmd/internal/obj/ppc64/obj9.go index 5b7612429e..a55c402c44 100644 --- a/src/cmd/internal/obj/ppc64/obj9.go +++ b/src/cmd/internal/obj/ppc64/obj9.go @@ -37,6 +37,7 @@ import ( "internal/abi" "internal/buildcfg" "log" + "math" "math/bits" "strings" ) @@ -90,6 +91,29 @@ func isNOTOCfunc(name string) bool { } } +// Try converting FMOVD/FMOVS to XXSPLTIDP. If it is converted, +// return true. +func convertFMOVtoXXSPLTIDP(p *obj.Prog) bool { + if p.From.Type != obj.TYPE_FCONST || buildcfg.GOPPC64 < 10 { + return false + } + v := p.From.Val.(float64) + if float64(float32(v)) != v { + return false + } + // Secondly, is this value a normal value? + ival := int64(math.Float32bits(float32(v))) + isDenorm := ival&0x7F800000 == 0 && ival&0x007FFFFF != 0 + if !isDenorm { + p.As = AXXSPLTIDP + p.From.Type = obj.TYPE_CONST + p.From.Offset = ival + // Convert REG_Fx into equivalent REG_VSx + p.To.Reg = REG_VS0 + (p.To.Reg & 31) + } + return !isDenorm +} + func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) { p.From.Class = 0 p.To.Class = 0 @@ -111,7 +135,7 @@ func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) { // Rewrite float constants to values stored in memory. switch p.As { case AFMOVS: - if p.From.Type == obj.TYPE_FCONST { + if p.From.Type == obj.TYPE_FCONST && !convertFMOVtoXXSPLTIDP(p) { f32 := float32(p.From.Val.(float64)) p.From.Type = obj.TYPE_MEM p.From.Sym = ctxt.Float32Sym(f32) @@ -123,7 +147,7 @@ func progedit(ctxt *obj.Link, p *obj.Prog, newprog obj.ProgAlloc) { if p.From.Type == obj.TYPE_FCONST { f64 := p.From.Val.(float64) // Constant not needed in memory for float +/- 0 - if f64 != 0 { + if f64 != 0 && !convertFMOVtoXXSPLTIDP(p) { p.From.Type = obj.TYPE_MEM p.From.Sym = ctxt.Float64Sym(f64) p.From.Name = obj.NAME_EXTERN |