diff options
Diffstat (limited to 'src/runtime/cgo/asm_arm.s')
| -rw-r--r-- | src/runtime/cgo/asm_arm.s | 61 |
1 files changed, 31 insertions, 30 deletions
diff --git a/src/runtime/cgo/asm_arm.s b/src/runtime/cgo/asm_arm.s index 60132c14a8..ea55e173c1 100644 --- a/src/runtime/cgo/asm_arm.s +++ b/src/runtime/cgo/asm_arm.s @@ -5,51 +5,52 @@ #include "textflag.h" // Called by C code generated by cmd/cgo. -// func crosscall2(fn func(a unsafe.Pointer, n int32, ctxt uintptr), a unsafe.Pointer, n int32, ctxt uintptr) -// Saves C callee-saved registers and calls fn with three arguments. +// func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr) +// Saves C callee-saved registers and calls cgocallback with three arguments. +// fn is the PC of a func(a unsafe.Pointer) function. TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0 - /* - * We still need to save all callee save register as before, and then - * push 3 args for fn (R1, R2, R3). - * Also note that at procedure entry in gc world, 4(R13) will be the - * first arg, so we must push another dummy reg (R0) for 0(R13). - * Additionally, runtime·load_g will clobber R0, so we need to save R0 - * nevertheless. - */ SUB $(8*9), R13 // Reserve space for the floating point registers. - MOVM.WP [R0, R1, R2, R3, R4, R5, R6, R7, R8, R9, g, R11, R12, R14], (R13) + // The C arguments arrive in R0, R1, R2, and R3. We want to + // pass R0, R1, and R3 to Go, so we push those on the stack. + // Also, save C callee-save registers R4-R12. + MOVM.WP [R0, R1, R3, R4, R5, R6, R7, R8, R9, g, R11, R12], (R13) + // Finally, save the link register R14. This also puts the + // arguments we pushed for cgocallback where they need to be, + // starting at 4(R13). + MOVW.W R14, -4(R13) // Skip floating point registers on GOARM < 6. MOVB runtime·goarm(SB), R11 CMP $6, R11 BLT skipfpsave - MOVD F8, (14*4+8*1)(R13) - MOVD F9, (14*4+8*2)(R13) - MOVD F10, (14*4+8*3)(R13) - MOVD F11, (14*4+8*4)(R13) - MOVD F12, (14*4+8*5)(R13) - MOVD F13, (14*4+8*6)(R13) - MOVD F14, (14*4+8*7)(R13) - MOVD F15, (14*4+8*8)(R13) + MOVD F8, (13*4+8*1)(R13) + MOVD F9, (13*4+8*2)(R13) + MOVD F10, (13*4+8*3)(R13) + MOVD F11, (13*4+8*4)(R13) + MOVD F12, (13*4+8*5)(R13) + MOVD F13, (13*4+8*6)(R13) + MOVD F14, (13*4+8*7)(R13) + MOVD F15, (13*4+8*8)(R13) skipfpsave: BL runtime·load_g(SB) - MOVW R15, R14 // R15 is PC. - MOVW 0(R13), R15 + // We set up the arguments to cgocallback when saving registers above. + BL runtime·cgocallback(SB) MOVB runtime·goarm(SB), R11 CMP $6, R11 BLT skipfprest - MOVD (14*4+8*1)(R13), F8 - MOVD (14*4+8*2)(R13), F9 - MOVD (14*4+8*3)(R13), F10 - MOVD (14*4+8*4)(R13), F11 - MOVD (14*4+8*5)(R13), F12 - MOVD (14*4+8*6)(R13), F13 - MOVD (14*4+8*7)(R13), F14 - MOVD (14*4+8*8)(R13), F15 + MOVD (13*4+8*1)(R13), F8 + MOVD (13*4+8*2)(R13), F9 + MOVD (13*4+8*3)(R13), F10 + MOVD (13*4+8*4)(R13), F11 + MOVD (13*4+8*5)(R13), F12 + MOVD (13*4+8*6)(R13), F13 + MOVD (13*4+8*7)(R13), F14 + MOVD (13*4+8*8)(R13), F15 skipfprest: - MOVM.IAW (R13), [R0, R1, R2, R3, R4, R5, R6, R7, R8, R9, g, R11, R12, R14] + MOVW.P 4(R13), R14 + MOVM.IAW (R13), [R0, R1, R3, R4, R5, R6, R7, R8, R9, g, R11, R12] ADD $(8*9), R13 MOVW R14, R15 |