cmd/compile/internal/x86: avoid CX in a couple of places in the int64 code
I want to use CX as a scratch register in position independent code and these
uses are easy to remove.
Change-Id: I9e3cb470d7f0000d85786c30bd769d9ec86d532a
Reviewed-on: https://go-review.googlesource.com/16382
Reviewed-by: Ian Lance Taylor <iant@golang.org>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
diff --git a/src/cmd/compile/internal/x86/cgen64.go b/src/cmd/compile/internal/x86/cgen64.go
index 9dffa61..7e40a32 100644
--- a/src/cmd/compile/internal/x86/cgen64.go
+++ b/src/cmd/compile/internal/x86/cgen64.go
@@ -113,19 +113,18 @@
gins(x86.ASUBL, &lo2, &ax)
gins(x86.ASBBL, &hi2, &dx)
- // let's call the next two EX and FX.
case gc.OMUL:
- var ex gc.Node
+ // let's call the next three EX, FX and GX
+ var ex, fx, gx gc.Node
gc.Regalloc(&ex, gc.Types[gc.TPTR32], nil)
-
- var fx gc.Node
gc.Regalloc(&fx, gc.Types[gc.TPTR32], nil)
+ gc.Regalloc(&gx, gc.Types[gc.TPTR32], nil)
- // load args into DX:AX and EX:CX.
+ // load args into DX:AX and EX:GX.
gins(x86.AMOVL, &lo1, &ax)
gins(x86.AMOVL, &hi1, &dx)
- gins(x86.AMOVL, &lo2, &cx)
+ gins(x86.AMOVL, &lo2, &gx)
gins(x86.AMOVL, &hi2, &ex)
// if DX and EX are zero, use 32 x 32 -> 64 unsigned multiply.
@@ -133,25 +132,26 @@
gins(x86.AORL, &ex, &fx)
p1 := gc.Gbranch(x86.AJNE, nil, 0)
- gins(x86.AMULL, &cx, nil) // implicit &ax
+ gins(x86.AMULL, &gx, nil) // implicit &ax
p2 := gc.Gbranch(obj.AJMP, nil, 0)
gc.Patch(p1, gc.Pc)
// full 64x64 -> 64, from 32x32 -> 64.
- gins(x86.AIMULL, &cx, &dx)
+ gins(x86.AIMULL, &gx, &dx)
gins(x86.AMOVL, &ax, &fx)
gins(x86.AIMULL, &ex, &fx)
gins(x86.AADDL, &dx, &fx)
- gins(x86.AMOVL, &cx, &dx)
+ gins(x86.AMOVL, &gx, &dx)
gins(x86.AMULL, &dx, nil) // implicit &ax
gins(x86.AADDL, &fx, &dx)
gc.Patch(p2, gc.Pc)
gc.Regfree(&ex)
gc.Regfree(&fx)
+ gc.Regfree(&gx)
- // We only rotate by a constant c in [0,64).
+ // We only rotate by a constant c in [0,64).
// if c >= 32:
// lo, hi = hi, lo
// c -= 32
