github.com/c12o16h1/go/src@v0.0.0-20200114212001-5a151c0f00ed/runtime/signal_ppc64x.go (about) 1 // Copyright 2014 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 // +build aix linux 6 // +build ppc64 ppc64le 7 8 package runtime 9 10 import ( 11 "runtime/internal/sys" 12 "unsafe" 13 ) 14 15 func dumpregs(c *sigctxt) { 16 print("r0 ", hex(c.r0()), "\t") 17 print("r1 ", hex(c.r1()), "\n") 18 print("r2 ", hex(c.r2()), "\t") 19 print("r3 ", hex(c.r3()), "\n") 20 print("r4 ", hex(c.r4()), "\t") 21 print("r5 ", hex(c.r5()), "\n") 22 print("r6 ", hex(c.r6()), "\t") 23 print("r7 ", hex(c.r7()), "\n") 24 print("r8 ", hex(c.r8()), "\t") 25 print("r9 ", hex(c.r9()), "\n") 26 print("r10 ", hex(c.r10()), "\t") 27 print("r11 ", hex(c.r11()), "\n") 28 print("r12 ", hex(c.r12()), "\t") 29 print("r13 ", hex(c.r13()), "\n") 30 print("r14 ", hex(c.r14()), "\t") 31 print("r15 ", hex(c.r15()), "\n") 32 print("r16 ", hex(c.r16()), "\t") 33 print("r17 ", hex(c.r17()), "\n") 34 print("r18 ", hex(c.r18()), "\t") 35 print("r19 ", hex(c.r19()), "\n") 36 print("r20 ", hex(c.r20()), "\t") 37 print("r21 ", hex(c.r21()), "\n") 38 print("r22 ", hex(c.r22()), "\t") 39 print("r23 ", hex(c.r23()), "\n") 40 print("r24 ", hex(c.r24()), "\t") 41 print("r25 ", hex(c.r25()), "\n") 42 print("r26 ", hex(c.r26()), "\t") 43 print("r27 ", hex(c.r27()), "\n") 44 print("r28 ", hex(c.r28()), "\t") 45 print("r29 ", hex(c.r29()), "\n") 46 print("r30 ", hex(c.r30()), "\t") 47 print("r31 ", hex(c.r31()), "\n") 48 print("pc ", hex(c.pc()), "\t") 49 print("ctr ", hex(c.ctr()), "\n") 50 print("link ", hex(c.link()), "\t") 51 print("xer ", hex(c.xer()), "\n") 52 print("ccr ", hex(c.ccr()), "\t") 53 print("trap ", hex(c.trap()), "\n") 54 } 55 56 //go:nosplit 57 //go:nowritebarrierrec 58 func (c *sigctxt) sigpc() uintptr { return uintptr(c.pc()) } 59 60 func (c *sigctxt) sigsp() uintptr { return uintptr(c.sp()) } 61 func (c *sigctxt) siglr() uintptr { return uintptr(c.link()) } 62 63 // preparePanic sets up the stack to look like a call to sigpanic. 64 func (c *sigctxt) preparePanic(sig uint32, gp *g) { 65 // We arrange link, and pc to pretend the panicking 66 // function calls sigpanic directly. 67 // Always save LINK to stack so that panics in leaf 68 // functions are correctly handled. This smashes 69 // the stack frame but we're not going back there 70 // anyway. 71 sp := c.sp() - sys.MinFrameSize 72 c.set_sp(sp) 73 *(*uint64)(unsafe.Pointer(uintptr(sp))) = c.link() 74 75 pc := gp.sigpc 76 77 if shouldPushSigpanic(gp, pc, uintptr(c.link())) { 78 // Make it look the like faulting PC called sigpanic. 79 c.set_link(uint64(pc)) 80 } 81 82 // In case we are panicking from external C code 83 c.set_r0(0) 84 c.set_r30(uint64(uintptr(unsafe.Pointer(gp)))) 85 c.set_r12(uint64(funcPC(sigpanic))) 86 c.set_pc(uint64(funcPC(sigpanic))) 87 } 88 89 const pushCallSupported = true 90 91 func (c *sigctxt) pushCall(targetPC uintptr) { 92 // Push the LR to stack, as we'll clobber it in order to 93 // push the call. The function being pushed is responsible 94 // for restoring the LR and setting the SP back. 95 // This extra space is known to gentraceback. 96 sp := c.sp() - sys.MinFrameSize 97 c.set_sp(sp) 98 *(*uint64)(unsafe.Pointer(uintptr(sp))) = c.link() 99 // In PIC mode, we'll set up (i.e. clobber) R2 on function 100 // entry. Save it ahead of time. 101 // In PIC mode it requires R12 points to the function entry, 102 // so we'll set it up when pushing the call. Save it ahead 103 // of time as well. 104 // 8(SP) and 16(SP) are unused space in the reserved 105 // MinFrameSize (32) bytes. 106 *(*uint64)(unsafe.Pointer(uintptr(sp) + 8)) = c.r2() 107 *(*uint64)(unsafe.Pointer(uintptr(sp) + 16)) = c.r12() 108 // Set up PC and LR to pretend the function being signaled 109 // calls targetPC at the faulting PC. 110 c.set_link(c.pc()) 111 c.set_r12(uint64(targetPC)) 112 c.set_pc(uint64(targetPC)) 113 }