runtime: remove unused arm assembly for div/mod

Also add runtime· prefixes to the code that is still used.

Fixes #19507

Change-Id: Ib6da6b2a9e398061d3f93958ee1258295b6cc33b
Reviewed-on: https://go-review.googlesource.com/45699
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

diff --git a/src/cmd/internal/obj/arm/obj5.go b/src/cmd/internal/obj/arm/obj5.go
index 858d06ab7900b7849e4cddb51123b8ed507760f9..32c4643166508dddeffb0ff7f0b375f78e93d599 100644 (file)
--- a/src/cmd/internal/obj/arm/obj5.go
+++ b/src/cmd/internal/obj/arm/obj5.go
@@ -637,7 +637,7 @@ func (c *ctxt5) softfloat() {
                return
        }
 
-       symsfloat := c.ctxt.Lookup("_sfloat")
+       symsfloat := c.ctxt.Lookup("runtime._sfloat")
 
        wasfloat := 0
        for p := c.cursym.Func.Text; p != nil; p = p.Link {
@@ -689,7 +689,7 @@ func (c *ctxt5) softfloat() {
                        next = c.newprog()
                        *next = *p
 
-                       // BL _sfloat(SB)
+                       // BL runtime·_sfloat(SB)
                        *p = obj.Prog{}
                        p.Ctxt = c.ctxt
                        p.Link = next

diff --git a/src/cmd/vet/all/whitelist/arm.txt b/src/cmd/vet/all/whitelist/arm.txt
index 7eb0132a393206f386eb7936dae6ab623b839011..c0ab9de67d02c94c03d0955e858e300385e0bb02 100644 (file)
--- a/src/cmd/vet/all/whitelist/arm.txt
+++ b/src/cmd/vet/all/whitelist/arm.txt
@@ -19,7 +19,6 @@ runtime/duff_arm.s: [arm] duffcopy: function duffcopy missing Go declaration
 runtime/tls_arm.s: [arm] save_g: function save_g missing Go declaration
 runtime/tls_arm.s: [arm] load_g: function load_g missing Go declaration
 runtime/tls_arm.s: [arm] _initcgo: function _initcgo missing Go declaration
-runtime/vlop_arm.s: [arm] udiv: function udiv missing Go declaration
 
 // Clearer using FP than SP, but that requires named offsets.
 runtime/asm_arm.s: [arm] rt0_go: use of 4(R13) points beyond argument frame

diff --git a/src/runtime/softfloat_arm.go b/src/runtime/softfloat_arm.go
index 3cbb4b3fc0d2854f86d42c3516c559b8ba93430f..8519f4cbd56a2a6a4704411ae5d7e43e7a7a852f 100644 (file)
--- a/src/runtime/softfloat_arm.go
+++ b/src/runtime/softfloat_arm.go
@@ -653,3 +653,8 @@ func sfloat2(pc uint32, regs *[15]uint32) uint32 {
        }
        return pc
 }
+
+// Stubs to pacify vet. Not safe to call from Go.
+// Calls to these functions are inserted by the compiler.
+func _sfloat()
+func udiv()

diff --git a/src/runtime/vlop_arm.s b/src/runtime/vlop_arm.s
index 3f2aa27f83078892de80284742cb2dc91ec78a88..7489a65071831bd795884a42032c1dec1014aed1 100644 (file)
--- a/src/runtime/vlop_arm.s
+++ b/src/runtime/vlop_arm.s
@@ -28,26 +28,10 @@
 #include "funcdata.h"
 #include "textflag.h"
 
-/* replaced use of R10 by R11 because the former can be the data segment base register */
-
-TEXT _mulv(SB), NOSPLIT, $0
-       MOVW    l0+0(FP), R2    /* l0 */
-       MOVW    h0+4(FP), R11   /* h0 */
-       MOVW    l1+8(FP), R4    /* l1 */
-       MOVW    h1+12(FP), R5   /* h1 */
-       MULLU   R4, R2, (R7,R6)
-       MUL     R11, R4, R8
-       ADD     R8, R7
-       MUL     R2, R5, R8
-       ADD     R8, R7
-       MOVW    R6, ret_lo+16(FP)
-       MOVW    R7, ret_hi+20(FP)
-       RET
-
 // trampoline for _sfloat2. passes LR as arg0 and
 // saves registers R0-R13 and CPSR on the stack. R0-R12 and CPSR flags can
 // be changed by _sfloat2.
-TEXT _sfloat(SB), NOSPLIT, $68-0 // 4 arg + 14*4 saved regs + cpsr + return value
+TEXT runtime·_sfloat(SB), NOSPLIT, $68-0 // 4 arg + 14*4 saved regs + cpsr + return value
        MOVW    R14, 4(R13)
        MOVW    R0, 8(R13)
        MOVW    $12(R13), R0
@@ -215,118 +199,6 @@ DATA fast_udiv_tab<>+0x38(SB)/4, $0x85868788
 DATA fast_udiv_tab<>+0x3c(SB)/4, $0x81828384
 GLOBL fast_udiv_tab<>(SB), RODATA, $64
 
-// The linker will pass numerator in R8
-#define Rn R8
-// The linker expects the result in RTMP
-#define RTMP R11
-
-TEXT _divu(SB), NOSPLIT, $16-0
-       // It's not strictly true that there are no local pointers.
-       // It could be that the saved registers Rq, Rr, Rs, and Rm
-       // contain pointers. However, the only way this can matter
-       // is if the stack grows (which it can't, udiv is nosplit)
-       // or if a fault happens and more frames are added to
-       // the stack due to deferred functions.
-       // In the latter case, the stack can grow arbitrarily,
-       // and garbage collection can happen, and those
-       // operations care about pointers, but in that case
-       // the calling frame is dead, and so are the saved
-       // registers. So we can claim there are no pointers here.
-       NO_LOCAL_POINTERS
-       MOVW    Rq, 4(R13)
-       MOVW    Rr, 8(R13)
-       MOVW    Rs, 12(R13)
-       MOVW    RM, 16(R13)
-
-       MOVW    Rn, Rr                  /* numerator */
-       MOVW    g_m(g), Rq
-       MOVW    m_divmod(Rq), Rq        /* denominator */
-       BL      runtime·udiv(SB)
-       MOVW    Rq, RTMP
-       MOVW    4(R13), Rq
-       MOVW    8(R13), Rr
-       MOVW    12(R13), Rs
-       MOVW    16(R13), RM
-       RET
-
-TEXT _modu(SB), NOSPLIT, $16-0
-       NO_LOCAL_POINTERS
-       MOVW    Rq, 4(R13)
-       MOVW    Rr, 8(R13)
-       MOVW    Rs, 12(R13)
-       MOVW    RM, 16(R13)
-
-       MOVW    Rn, Rr                  /* numerator */
-       MOVW    g_m(g), Rq
-       MOVW    m_divmod(Rq), Rq        /* denominator */
-       BL      runtime·udiv(SB)
-       MOVW    Rr, RTMP
-       MOVW    4(R13), Rq
-       MOVW    8(R13), Rr
-       MOVW    12(R13), Rs
-       MOVW    16(R13), RM
-       RET
-
-TEXT _div(SB),NOSPLIT,$16-0
-       NO_LOCAL_POINTERS
-       MOVW    Rq, 4(R13)
-       MOVW    Rr, 8(R13)
-       MOVW    Rs, 12(R13)
-       MOVW    RM, 16(R13)
-       MOVW    Rn, Rr                  /* numerator */
-       MOVW    g_m(g), Rq
-       MOVW    m_divmod(Rq), Rq        /* denominator */
-       CMP     $0, Rr
-       BGE     d1
-       RSB     $0, Rr, Rr
-       CMP     $0, Rq
-       BGE     d2
-       RSB     $0, Rq, Rq
-d0:
-       BL      runtime·udiv(SB)       /* none/both neg */
-       MOVW    Rq, RTMP
-       B       out1
-d1:
-       CMP     $0, Rq
-       BGE     d0
-       RSB     $0, Rq, Rq
-d2:
-       BL      runtime·udiv(SB)       /* one neg */
-       RSB     $0, Rq, RTMP
-out1:
-       MOVW    4(R13), Rq
-       MOVW    8(R13), Rr
-       MOVW    12(R13), Rs
-       MOVW    16(R13), RM
-       RET
-
-TEXT _mod(SB),NOSPLIT,$16-0
-       NO_LOCAL_POINTERS
-       MOVW    Rq, 4(R13)
-       MOVW    Rr, 8(R13)
-       MOVW    Rs, 12(R13)
-       MOVW    RM, 16(R13)
-       MOVW    Rn, Rr                  /* numerator */
-       MOVW    g_m(g), Rq
-       MOVW    m_divmod(Rq), Rq        /* denominator */
-       CMP     $0, Rq
-       RSB.LT  $0, Rq, Rq
-       CMP     $0, Rr
-       BGE     m1
-       RSB     $0, Rr, Rr
-       BL      runtime·udiv(SB)       /* neg numerator */
-       RSB     $0, Rr, RTMP
-       B       out
-m1:
-       BL      runtime·udiv(SB)       /* pos numerator */
-       MOVW    Rr, RTMP
-out:
-       MOVW    4(R13), Rq
-       MOVW    8(R13), Rr
-       MOVW    12(R13), Rs
-       MOVW    16(R13), RM
-       RET
-
 // _mul64by32 and _div64by32 not implemented on arm
 TEXT runtime·_mul64by32(SB), NOSPLIT, $0
        MOVW    $0, R0