* [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM @ 2015-04-28 15:51 Martin Galvan 2015-04-28 16:22 ` Ramana Radhakrishnan 0 siblings, 1 reply; 6+ messages in thread From: Martin Galvan @ 2015-04-28 15:51 UTC (permalink / raw) To: gcc-patches This patch adds CFI directives to the soft floating point support code for ARM. Previously, if we tried to do a backtrace from that code in a debug session we'd get something like this: (gdb) bt #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1082 #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1158 #2 0xf5c28f5c in ?? () Backtrace stopped: previous frame identical to this frame (corrupt stack?) Now we'll get something like this: (gdb) bt #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1156 #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1263 #2 0x00000dc8 in __aeabi_dcmpeq () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1285 #3 0x00000504 in main () I have a company-wide copyright assignment. I don't have commit access, though, so it would be great if anyone could commit this for me. Thanks a lot! libgcc/ChangeLog: 2015-04-23 Martin Galvan <martin.galvan@tallertechnologies.com> * config/arm/lib1funcs.S (CFI_START_FUNCTION, CFI_END_FUNCTION): New macros. * config/arm/ieee754-df.S: Add CFI directives. * config/arm/ieee754-sf.S: Add CFI directives. --- libgcc/config/arm/ieee754-df.S | 177 ++- libgcc/config/arm/ieee754-sf.S | 1727 ++++++++++++++------------- libgcc/config/arm/lib1funcs.S | 10 + 3 files changed, 1074 insertions(+), 840 deletions(-) diff --git a/libgcc/config/arm/ieee754-df.S b/libgcc/config/arm/ieee754-df.S index f75630b..d1f9066 100644 --- a/libgcc/config/arm/ieee754-df.S +++ b/libgcc/config/arm/ieee754-df.S @@ -33,8 +33,12 @@ * Only the default rounding mode is intended for best performances. * Exceptions aren't supported yet, but that can be added quite easily * if necessary without impacting performances. + * + * In the CFI related comments, 'previousOffset' refers to the previous offset + * from sp used to compute the CFA. */ + .cfi_sections .debug_frame #ifndef __ARMEB__ #define xl r0 @@ -53,11 +57,13 @@ ARM_FUNC_START negdf2 ARM_FUNC_ALIAS aeabi_dneg negdf2 + CFI_START_FUNCTION @ flip sign bit eor xh, xh, #0x80000000 RET + CFI_END_FUNCTION FUNC_END aeabi_dneg FUNC_END negdf2 @@ -66,6 +72,7 @@ ARM_FUNC_ALIAS aeabi_dneg negdf2 #ifdef L_arm_addsubdf3 ARM_FUNC_START aeabi_drsub + CFI_START_FUNCTION eor xh, xh, #0x80000000 @ flip sign bit of first arg b 1f @@ -81,7 +88,11 @@ ARM_FUNC_ALIAS aeabi_dsub subdf3 ARM_FUNC_START adddf3 ARM_FUNC_ALIAS aeabi_dadd adddf3 -1: do_push {r4, r5, lr} +1: do_push {r4, r5, lr} @ sp -= 12 + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 8 + .cfi_rel_offset r5, 4 + .cfi_rel_offset lr, 8 @ Look for zeroes, equal values, INF, or NAN. shift1 lsl, r4, xh, #1 @@ -148,6 +159,11 @@ ARM_FUNC_ALIAS aeabi_dadd adddf3 @ Since this is not common case, rescale them off line. teq r4, r5 beq LSYM(Lad_d) + +@ CFI note: we're lucky that the branches to Lad_* that appear after this function +@ have a CFI state that's exactly the same as the one we're in at this +@ point. Otherwise the CFI would change to a different state after the branch, +@ which would be disastrous for backtracing. LSYM(Lad_x): @ Compensate for the exponent overlapping the mantissa MSB added later @@ -413,6 +429,7 @@ LSYM(Lad_i): orrne xh, xh, #0x00080000 @ quiet NAN RETLDM "r4, r5" + CFI_END_FUNCTION FUNC_END aeabi_dsub FUNC_END subdf3 FUNC_END aeabi_dadd @@ -420,12 +437,19 @@ LSYM(Lad_i): ARM_FUNC_START floatunsidf ARM_FUNC_ALIAS aeabi_ui2d floatunsidf + CFI_START_FUNCTION teq r0, #0 do_it eq, t moveq r1, #0 RETc(eq) - do_push {r4, r5, lr} + + do_push {r4, r5, lr} @ sp -= 12 + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. + .cfi_rel_offset r5, 4 + .cfi_rel_offset lr, 8 + mov r4, #0x400 @ initial exponent add r4, r4, #(52-1 - 1) mov r5, #0 @ sign bit is 0 @@ -435,17 +459,25 @@ ARM_FUNC_ALIAS aeabi_ui2d floatunsidf mov xh, #0 b LSYM(Lad_l) + CFI_END_FUNCTION FUNC_END aeabi_ui2d FUNC_END floatunsidf ARM_FUNC_START floatsidf ARM_FUNC_ALIAS aeabi_i2d floatsidf + CFI_START_FUNCTION teq r0, #0 do_it eq, t moveq r1, #0 RETc(eq) - do_push {r4, r5, lr} + + do_push {r4, r5, lr} @ sp -= 12 + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. + .cfi_rel_offset r5, 4 + .cfi_rel_offset lr, 8 + mov r4, #0x400 @ initial exponent add r4, r4, #(52-1 - 1) ands r5, r0, #0x80000000 @ sign bit in r5 @@ -457,11 +489,13 @@ ARM_FUNC_ALIAS aeabi_i2d floatsidf mov xh, #0 b LSYM(Lad_l) + CFI_END_FUNCTION FUNC_END aeabi_i2d FUNC_END floatsidf ARM_FUNC_START extendsfdf2 ARM_FUNC_ALIAS aeabi_f2d extendsfdf2 + CFI_START_FUNCTION movs r2, r0, lsl #1 @ toss sign bit mov xh, r2, asr #3 @ stretch exponent @@ -480,34 +514,54 @@ ARM_FUNC_ALIAS aeabi_f2d extendsfdf2 @ value was denormalized. We can normalize it now. do_push {r4, r5, lr} + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. + .cfi_rel_offset r5, 4 + .cfi_rel_offset lr, 8 + mov r4, #0x380 @ setup corresponding exponent and r5, xh, #0x80000000 @ move sign bit in r5 bic xh, xh, #0x80000000 b LSYM(Lad_l) + CFI_END_FUNCTION FUNC_END aeabi_f2d FUNC_END extendsfdf2 ARM_FUNC_START floatundidf ARM_FUNC_ALIAS aeabi_ul2d floatundidf + CFI_START_FUNCTION + .cfi_remember_state @ Save the current CFA state. orrs r2, r0, r1 do_it eq RETc(eq) - do_push {r4, r5, lr} + do_push {r4, r5, lr} @ sp -= 12 + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8 + .cfi_rel_offset r5, 4 + .cfi_rel_offset lr, 8 mov r5, #0 b 2f ARM_FUNC_START floatdidf ARM_FUNC_ALIAS aeabi_l2d floatdidf + .cfi_restore_state + @ Restore the CFI state we saved above. If we didn't do this then the + @ following instructions would have the CFI state that was set by the + @ offset adjustments made in floatundidf. orrs r2, r0, r1 do_it eq RETc(eq) - do_push {r4, r5, lr} + do_push {r4, r5, lr} @ sp -= 12 + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 8 + .cfi_rel_offset r5, 4 + .cfi_rel_offset lr, 8 ands r5, ah, #0x80000000 @ sign bit in r5 bpl 2f @@ -550,6 +604,7 @@ ARM_FUNC_ALIAS aeabi_l2d floatdidf add r4, r4, r2 b LSYM(Lad_p) + CFI_END_FUNCTION FUNC_END floatdidf FUNC_END aeabi_l2d FUNC_END floatundidf @@ -561,7 +616,14 @@ ARM_FUNC_ALIAS aeabi_l2d floatdidf ARM_FUNC_START muldf3 ARM_FUNC_ALIAS aeabi_dmul muldf3 - do_push {r4, r5, r6, lr} + CFI_START_FUNCTION + + do_push {r4, r5, r6, lr} @ sp -= 16 + .cfi_adjust_cfa_offset 16 @ CFA is now sp + previousOffset + 16 + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 12. + .cfi_rel_offset r5, 4 + .cfi_rel_offset r6, 8 + .cfi_rel_offset lr, 12 @ Mask out exponents, trap any zero/denormal/INF/NAN. mov ip, #0xff @@ -596,7 +658,16 @@ ARM_FUNC_ALIAS aeabi_dmul muldf3 and r6, r6, #0x80000000 @ Well, no way to make it shorter without the umull instruction. - stmfd sp!, {r6, r7, r8, r9, sl, fp} + stmfd sp!, {r6, r7, r8, r9, sl, fp} @ sp -= 24 + .cfi_remember_state @ Save the current CFI state. + .cfi_adjust_cfa_offset 24 @ CFA is now sp + previousOffset + 24. + .cfi_rel_offset r6, 0 @ Registers are saved from sp to sp + 20. + .cfi_rel_offset r7, 4 + .cfi_rel_offset r8, 8 + .cfi_rel_offset r9, 12 + .cfi_rel_offset sl, 16 + .cfi_rel_offset fp, 20 + mov r7, xl, lsr #16 mov r8, yl, lsr #16 mov r9, xh, lsr #16 @@ -648,8 +719,8 @@ ARM_FUNC_ALIAS aeabi_dmul muldf3 mul fp, xh, yh adcs r5, r5, fp adc r6, r6, #0 - ldmfd sp!, {yl, r7, r8, r9, sl, fp} - + ldmfd sp!, {yl, r7, r8, r9, sl, fp} @ sp += 24 + .cfi_restore_state @ Restore the previous CFI state. #else @ Here is the actual multiplication. @@ -715,7 +786,6 @@ LSYM(Lml_1): orr xh, xh, #0x00100000 mov lr, #0 subs r4, r4, #1 - LSYM(Lml_u): @ Overflow? bgt LSYM(Lml_o) @@ -863,13 +933,20 @@ LSYM(Lml_n): orr xh, xh, #0x00f80000 RETLDM "r4, r5, r6" + CFI_END_FUNCTION FUNC_END aeabi_dmul FUNC_END muldf3 ARM_FUNC_START divdf3 ARM_FUNC_ALIAS aeabi_ddiv divdf3 + CFI_START_FUNCTION do_push {r4, r5, r6, lr} + .cfi_adjust_cfa_offset 16 + .cfi_rel_offset r4, 0 + .cfi_rel_offset r5, 4 + .cfi_rel_offset r6, 8 + .cfi_rel_offset lr, 12 @ Mask out exponents, trap any zero/denormal/INF/NAN. mov ip, #0xff @@ -1052,6 +1129,7 @@ LSYM(Ldv_s): bne LSYM(Lml_z) @ 0 / <non_zero> -> 0 b LSYM(Lml_n) @ 0 / 0 -> NAN + CFI_END_FUNCTION FUNC_END aeabi_ddiv FUNC_END divdf3 @@ -1063,6 +1141,7 @@ LSYM(Ldv_s): ARM_FUNC_START gtdf2 ARM_FUNC_ALIAS gedf2 gtdf2 + CFI_START_FUNCTION mov ip, #-1 b 1f @@ -1077,6 +1156,10 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 mov ip, #1 @ how should we specify unordered here? 1: str ip, [sp, #-4]! + .cfi_adjust_cfa_offset 4 @ CFA is now sp + previousOffset + 4. + @ We're not adding CFI for ip as it's pushed into the stack only because + @ it may be popped off later as a return value (i.e. we're not preserving + @ it anyways). @ Trap any INF/NAN first. mov ip, xh, lsl #1 @@ -1085,10 +1168,18 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 do_it ne COND(mvn,s,ne) ip, ip, asr #21 beq 3f + .cfi_remember_state + @ Save the current CFI state. This is done because the branch is conditional, + @ and if we don't take it we'll issue a .cfi_adjust_cfa_offset and return. + @ If we do take it, however, the .cfi_adjust_cfa_offset from the non-branch + @ code will affect the branch code as well. To avoid this we'll restore + @ the current state before executing the branch code. @ Test for equality. @ Note that 0.0 is equal to -0.0. 2: add sp, sp, #4 + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. + orrs ip, xl, xh, lsl #1 @ if x == 0.0 or -0.0 do_it eq, e COND(orr,s,eq) ip, yl, yh, lsl #1 @ and y == 0.0 or -0.0 @@ -1117,8 +1208,13 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 orr r0, r0, #1 RET - @ Look for a NAN. -3: mov ip, xh, lsl #1 +3: @ Look for a NAN. + + @ Restore the previous CFI state (i.e. keep the CFI state as it was + @ before the branch). + .cfi_restore_state + + mov ip, xh, lsl #1 mvns ip, ip, asr #21 bne 4f orrs ip, xl, xh, lsl #12 @@ -1128,9 +1224,13 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 bne 2b orrs ip, yl, yh, lsl #12 beq 2b @ y is not NAN + 5: ldr r0, [sp], #4 @ unordered return code + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. + RET + CFI_END_FUNCTION FUNC_END gedf2 FUNC_END gtdf2 FUNC_END ledf2 @@ -1140,6 +1240,7 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 FUNC_END cmpdf2 ARM_FUNC_START aeabi_cdrcmple + CFI_START_FUNCTION mov ip, r0 mov r0, r2 @@ -1149,12 +1250,16 @@ ARM_FUNC_START aeabi_cdrcmple mov r3, ip b 6f -ARM_FUNC_START aeabi_cdcmpeq +; ARM_FUNC_START aeabi_cdcmpeq ARM_FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq @ The status-returning routines are required to preserve all @ registers except ip, lr, and cpsr. 6: do_push {r0, lr} + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8. + .cfi_rel_offset r0, 0 @ Previous r0 is saved at sp. + .cfi_rel_offset lr, 4 @ Previous lr is saved at sp + 4. + ARM_CALL cmpdf2 @ Set the Z flag correctly, and the C flag unconditionally. cmp r0, #0 @@ -1162,59 +1267,86 @@ ARM_FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq @ that the first operand was smaller than the second. do_it mi cmnmi r0, #0 + RETLDM "r0" + CFI_END_FUNCTION FUNC_END aeabi_cdcmple FUNC_END aeabi_cdcmpeq FUNC_END aeabi_cdrcmple ARM_FUNC_START aeabi_dcmpeq + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cdcmple do_it eq, e moveq r0, #1 @ Equal to. movne r0, #0 @ Less than, greater than, or unordered. + RETLDM + CFI_END_FUNCTION FUNC_END aeabi_dcmpeq ARM_FUNC_START aeabi_dcmplt + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cdcmple do_it cc, e movcc r0, #1 @ Less than. movcs r0, #0 @ Equal to, greater than, or unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_dcmplt ARM_FUNC_START aeabi_dcmple + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cdcmple do_it ls, e movls r0, #1 @ Less than or equal to. movhi r0, #0 @ Greater than or unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_dcmple ARM_FUNC_START aeabi_dcmpge + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cdrcmple do_it ls, e movls r0, #1 @ Operand 2 is less than or equal to operand 1. movhi r0, #0 @ Operand 2 greater than operand 1, or unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_dcmpge ARM_FUNC_START aeabi_dcmpgt + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cdrcmple do_it cc, e movcc r0, #1 @ Operand 2 is less than operand 1. @@ -1222,6 +1354,7 @@ ARM_FUNC_START aeabi_dcmpgt @ or they are unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_dcmpgt #endif /* L_cmpdf2 */ @@ -1230,6 +1363,7 @@ ARM_FUNC_START aeabi_dcmpgt ARM_FUNC_START unorddf2 ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 + .cfi_startproc mov ip, xh, lsl #1 mvns ip, ip, asr #21 @@ -1247,6 +1381,7 @@ ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 3: mov r0, #1 @ arguments are unordered. RET + .cfi_endproc FUNC_END aeabi_dcmpun FUNC_END unorddf2 @@ -1256,6 +1391,7 @@ ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 ARM_FUNC_START fixdfsi ARM_FUNC_ALIAS aeabi_d2iz fixdfsi + CFI_START_FUNCTION @ check exponent range. mov r2, xh, lsl #1 @@ -1289,6 +1425,7 @@ ARM_FUNC_ALIAS aeabi_d2iz fixdfsi 4: mov r0, #0 @ How should we convert NAN? RET + CFI_END_FUNCTION FUNC_END aeabi_d2iz FUNC_END fixdfsi @@ -1298,6 +1435,7 @@ ARM_FUNC_ALIAS aeabi_d2iz fixdfsi ARM_FUNC_START fixunsdfsi ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi + CFI_START_FUNCTION @ check exponent range. movs r2, xh, lsl #1 @@ -1327,6 +1465,7 @@ ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi 4: mov r0, #0 @ How should we convert NAN? RET + CFI_END_FUNCTION FUNC_END aeabi_d2uiz FUNC_END fixunsdfsi @@ -1336,6 +1475,7 @@ ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi ARM_FUNC_START truncdfsf2 ARM_FUNC_ALIAS aeabi_d2f truncdfsf2 + CFI_START_FUNCTION @ check exponent range. mov r2, xh, lsl #1 @@ -1400,6 +1540,7 @@ ARM_FUNC_ALIAS aeabi_d2f truncdfsf2 orr r0, r0, #0x00800000 RET + CFI_END_FUNCTION FUNC_END aeabi_d2f FUNC_END truncdfsf2 diff --git a/libgcc/config/arm/ieee754-sf.S b/libgcc/config/arm/ieee754-sf.S index 3e76241..a93d40a 100644 --- a/libgcc/config/arm/ieee754-sf.S +++ b/libgcc/config/arm/ieee754-sf.S @@ -31,16 +31,21 @@ * Only the default rounding mode is intended for best performances. * Exceptions aren't supported yet, but that can be added quite easily * if necessary without impacting performances. + * + * In the CFI related comments, 'previousOffset' refers to the previous offset + * from sp used to compute the CFA. */ #ifdef L_arm_negsf2 ARM_FUNC_START negsf2 ARM_FUNC_ALIAS aeabi_fneg negsf2 + CFI_START_FUNCTION eor r0, r0, #0x80000000 @ flip sign bit RET + CFI_END_FUNCTION FUNC_END aeabi_fneg FUNC_END negsf2 @@ -49,6 +54,7 @@ ARM_FUNC_ALIAS aeabi_fneg negsf2 #ifdef L_arm_addsubsf3 ARM_FUNC_START aeabi_frsub + CFI_START_FUNCTION eor r0, r0, #0x80000000 @ flip sign bit of first arg b 1f @@ -284,6 +290,7 @@ LSYM(Lad_i): orrne r0, r0, #0x00400000 @ quiet NAN RET + CFI_END_FUNCTION FUNC_END aeabi_frsub FUNC_END aeabi_fadd FUNC_END addsf3 @@ -292,6 +299,7 @@ LSYM(Lad_i): ARM_FUNC_START floatunsisf ARM_FUNC_ALIAS aeabi_ui2f floatunsisf + CFI_START_FUNCTION mov r3, #0 b 1f @@ -316,6 +324,7 @@ ARM_FUNC_ALIAS aeabi_i2f floatsisf mov al, #0 b 2f + CFI_END_FUNCTION FUNC_END aeabi_i2f FUNC_END floatsisf FUNC_END aeabi_ui2f @@ -323,6 +332,7 @@ ARM_FUNC_ALIAS aeabi_i2f floatsisf ARM_FUNC_START floatundisf ARM_FUNC_ALIAS aeabi_ul2f floatundisf + CFI_START_FUNCTION orrs r2, r0, r1 do_it eq @@ -409,6 +419,7 @@ ARM_FUNC_ALIAS aeabi_l2f floatdisf biceq r0, r0, ip, lsr #31 RET + CFI_END_FUNCTION FUNC_END floatdisf FUNC_END aeabi_l2f FUNC_END floatundisf @@ -420,6 +431,7 @@ ARM_FUNC_ALIAS aeabi_l2f floatdisf ARM_FUNC_START mulsf3 ARM_FUNC_ALIAS aeabi_fmul mulsf3 + CFI_START_FUNCTION @ Mask out exponents, trap any zero/denormal/INF/NAN. mov ip, #0xff @@ -454,7 +466,13 @@ LSYM(Lml_x): and r3, ip, #0x80000000 @ Well, no way to make it shorter without the umull instruction. - do_push {r3, r4, r5} + do_push {r3, r4, r5} @ sp -= 12 + .cfi_remember_state @ Save the current CFI state + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 + .cfi_rel_offset r3, 0 @ Registers are saved from sp to sp + 8 + .cfi_rel_offset r4, 4 + .cfi_rel_offset r5, 8 + mov r4, r0, lsr #16 mov r5, r1, lsr #16 bic r0, r0, r4, lsl #16 @@ -465,7 +483,8 @@ LSYM(Lml_x): mla r0, r4, r1, r0 adds r3, r3, r0, lsl #16 adc r1, ip, r0, lsr #16 - do_pop {r0, r4, r5} + do_pop {r0, r4, r5} @ sp += 12 + .cfi_restore_state @ Restore the previous CFI state #else @@ -618,11 +637,13 @@ LSYM(Lml_n): orr r0, r0, #0x00c00000 RET + CFI_END_FUNCTION FUNC_END aeabi_fmul FUNC_END mulsf3 ARM_FUNC_START divsf3 ARM_FUNC_ALIAS aeabi_fdiv divsf3 + CFI_START_FUNCTION @ Mask out exponents, trap any zero/denormal/INF/NAN. mov ip, #0xff @@ -758,6 +779,7 @@ LSYM(Ldv_s): bne LSYM(Lml_z) @ 0 / <non_zero> -> 0 b LSYM(Lml_n) @ 0 / 0 -> NAN + CFI_END_FUNCTION FUNC_END aeabi_fdiv FUNC_END divsf3 @@ -782,6 +804,7 @@ LSYM(Ldv_s): ARM_FUNC_START gtsf2 ARM_FUNC_ALIAS gesf2 gtsf2 + CFI_START_FUNCTION mov ip, #-1 b 1f @@ -796,6 +819,10 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 mov ip, #1 @ how should we specify unordered here? 1: str ip, [sp, #-4]! + .cfi_adjust_cfa_offset 4 @ CFA is now sp + previousOffset + 4. + @ We're not adding CFI for ip as it's pushed into the stack only because + @ it may be popped off later as a return value (i.e. we're not preserving + @ it anyways). @ Trap any INF/NAN first. mov r2, r0, lsl #1 @@ -804,10 +831,18 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 do_it ne COND(mvn,s,ne) ip, r3, asr #24 beq 3f + .cfi_remember_state + @ Save the current CFI state. This is done because the branch is conditional, + @ and if we don't take it we'll issue a .cfi_adjust_cfa_offset and return. + @ If we do take it, however, the .cfi_adjust_cfa_offset from the non-branch + @ code will affect the branch code as well. To avoid this we'll restore + @ the current state before executing the branch code. @ Compare values. @ Note that 0.0 is equal to -0.0. 2: add sp, sp, #4 + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. + orrs ip, r2, r3, lsr #1 @ test if both are 0, clear C flag do_it ne teqne r0, r1 @ if not 0 compare sign @@ -823,8 +858,13 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 orrne r0, r0, #1 RET - @ Look for a NAN. -3: mvns ip, r2, asr #24 +3: @ Look for a NAN. + + @ Restore the previous CFI state (i.e. keep the CFI state as it was + @ before the branch). + .cfi_restore_state + + mvns ip, r2, asr #24 bne 4f movs ip, r0, lsl #9 bne 5f @ r0 is NAN @@ -832,9 +872,12 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 bne 2b movs ip, r1, lsl #9 beq 2b @ r1 is not NAN + 5: ldr r0, [sp], #4 @ return unordered code. + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. RET + CFI_END_FUNCTION FUNC_END gesf2 FUNC_END gtsf2 FUNC_END lesf2 @@ -844,6 +887,7 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 FUNC_END cmpsf2 ARM_FUNC_START aeabi_cfrcmple + CFI_START_FUNCTION mov ip, r0 mov r0, r1 @@ -856,6 +900,13 @@ ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq @ The status-returning routines are required to preserve all @ registers except ip, lr, and cpsr. 6: do_push {r0, r1, r2, r3, lr} + .cfi_adjust_cfa_offset 20 @ CFA is at sp + previousOffset + 20 + .cfi_rel_offset r0, 0 @ Registers are saved from sp to sp + 16 + .cfi_rel_offset r1, 4 + .cfi_rel_offset r2, 8 + .cfi_rel_offset r3, 12 + .cfi_rel_offset lr, 16 + ARM_CALL cmpsf2 @ Set the Z flag correctly, and the C flag unconditionally. cmp r0, #0 @@ -865,57 +916,82 @@ ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq cmnmi r0, #0 RETLDM "r0, r1, r2, r3" + CFI_END_FUNCTION FUNC_END aeabi_cfcmple FUNC_END aeabi_cfcmpeq FUNC_END aeabi_cfrcmple ARM_FUNC_START aeabi_fcmpeq + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cfcmple do_it eq, e moveq r0, #1 @ Equal to. movne r0, #0 @ Less than, greater than, or unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_fcmpeq ARM_FUNC_START aeabi_fcmplt + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cfcmple do_it cc, e movcc r0, #1 @ Less than. movcs r0, #0 @ Equal to, greater than, or unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_fcmplt ARM_FUNC_START aeabi_fcmple + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cfcmple do_it ls, e movls r0, #1 @ Less than or equal to. movhi r0, #0 @ Greater than or unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_fcmple ARM_FUNC_START aeabi_fcmpge + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cfrcmple do_it ls, e movls r0, #1 @ Operand 2 is less than or equal to operand 1. movhi r0, #0 @ Operand 2 greater than operand 1, or unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_fcmpge ARM_FUNC_START aeabi_fcmpgt + CFI_START_FUNCTION + + str lr, [sp, #-8]! @ sp -= 8 + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 + .cfi_rel_offset lr, 0 @ lr is at sp - str lr, [sp, #-8]! ARM_CALL aeabi_cfrcmple do_it cc, e movcc r0, #1 @ Operand 2 is less than operand 1. @@ -923,6 +999,7 @@ ARM_FUNC_START aeabi_fcmpgt @ or they are unordered. RETLDM + CFI_END_FUNCTION FUNC_END aeabi_fcmpgt #endif /* L_cmpsf2 */ @@ -931,6 +1008,7 @@ ARM_FUNC_START aeabi_fcmpgt ARM_FUNC_START unordsf2 ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 + CFI_START_FUNCTION mov r2, r0, lsl #1 mov r3, r1, lsl #1 @@ -947,6 +1025,7 @@ ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 3: mov r0, #1 @ arguments are unordered. RET + CFI_END_FUNCTION FUNC_END aeabi_fcmpun FUNC_END unordsf2 @@ -956,6 +1035,7 @@ ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 ARM_FUNC_START fixsfsi ARM_FUNC_ALIAS aeabi_f2iz fixsfsi + CFI_START_FUNCTION @ check exponent range. mov r2, r0, lsl #1 @@ -989,6 +1069,7 @@ ARM_FUNC_ALIAS aeabi_f2iz fixsfsi 4: mov r0, #0 @ What should we convert NAN to? RET + CFI_END_FUNCTION FUNC_END aeabi_f2iz FUNC_END fixsfsi @@ -998,6 +1079,7 @@ ARM_FUNC_ALIAS aeabi_f2iz fixsfsi ARM_FUNC_START fixunssfsi ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi + CFI_START_FUNCTION @ check exponent range. movs r2, r0, lsl #1 @@ -1027,6 +1109,7 @@ ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi 4: mov r0, #0 @ What should we convert NAN to? RET + CFI_END_FUNCTION FUNC_END aeabi_f2uiz FUNC_END fixunssfsi diff --git a/libgcc/config/arm/lib1funcs.S b/libgcc/config/arm/lib1funcs.S index d2d0d20..4b63924 100644 --- a/libgcc/config/arm/lib1funcs.S +++ b/libgcc/config/arm/lib1funcs.S @@ -1965,6 +1965,16 @@ LSYM(Lchange_\register): #endif /* Arch supports thumb. */ +.macro CFI_START_FUNCTION + .cfi_startproc + .cfi_remember_state +.endm + +.macro CFI_END_FUNCTION + .cfi_restore_state + .cfi_endproc +.endm + #ifndef __symbian__ #ifndef __ARM_ARCH_6M__ #include "ieee754-df.S" ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM 2015-04-28 15:51 [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM Martin Galvan @ 2015-04-28 16:22 ` Ramana Radhakrishnan 2015-04-28 17:10 ` Martin Galvan 0 siblings, 1 reply; 6+ messages in thread From: Ramana Radhakrishnan @ 2015-04-28 16:22 UTC (permalink / raw) To: Martin Galvan; +Cc: gcc-patches On Tue, Apr 28, 2015 at 4:19 PM, Martin Galvan <martin.galvan@tallertechnologies.com> wrote: > This patch adds CFI directives to the soft floating point support code for ARM. > > Previously, if we tried to do a backtrace from that code in a debug session we'd > get something like this: > > (gdb) bt > #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1082 > #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1158 > #2 0xf5c28f5c in ?? () > Backtrace stopped: previous frame identical to this frame (corrupt stack?) > > Now we'll get something like this: > > (gdb) bt > #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1156 > #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1263 > #2 0x00000dc8 in __aeabi_dcmpeq () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1285 > #3 0x00000504 in main () > > I have a company-wide copyright assignment. I don't have commit access, though, so it would be great if anyone could commit this for me. > > Thanks a lot! > this is OK , thanks. Sorry about the delay in reviewing this. Ramana > libgcc/ChangeLog: > 2015-04-23 Martin Galvan <martin.galvan@tallertechnologies.com> > > * config/arm/lib1funcs.S (CFI_START_FUNCTION, CFI_END_FUNCTION): > New macros. > * config/arm/ieee754-df.S: Add CFI directives. > * config/arm/ieee754-sf.S: Add CFI directives. > > --- > libgcc/config/arm/ieee754-df.S | 177 ++- > libgcc/config/arm/ieee754-sf.S | 1727 ++++++++++++++------------- > libgcc/config/arm/lib1funcs.S | 10 + > 3 files changed, 1074 insertions(+), 840 deletions(-) > > diff --git a/libgcc/config/arm/ieee754-df.S b/libgcc/config/arm/ieee754-df.S > index f75630b..d1f9066 100644 > --- a/libgcc/config/arm/ieee754-df.S > +++ b/libgcc/config/arm/ieee754-df.S > @@ -33,8 +33,12 @@ > * Only the default rounding mode is intended for best performances. > * Exceptions aren't supported yet, but that can be added quite easily > * if necessary without impacting performances. > + * > + * In the CFI related comments, 'previousOffset' refers to the previous offset > + * from sp used to compute the CFA. > */ > > + .cfi_sections .debug_frame > > #ifndef __ARMEB__ > #define xl r0 > @@ -53,11 +57,13 @@ > > ARM_FUNC_START negdf2 > ARM_FUNC_ALIAS aeabi_dneg negdf2 > + CFI_START_FUNCTION > > @ flip sign bit > eor xh, xh, #0x80000000 > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_dneg > FUNC_END negdf2 > > @@ -66,6 +72,7 @@ ARM_FUNC_ALIAS aeabi_dneg negdf2 > #ifdef L_arm_addsubdf3 > > ARM_FUNC_START aeabi_drsub > + CFI_START_FUNCTION > > eor xh, xh, #0x80000000 @ flip sign bit of first arg > b 1f > @@ -81,7 +88,11 @@ ARM_FUNC_ALIAS aeabi_dsub subdf3 > ARM_FUNC_START adddf3 > ARM_FUNC_ALIAS aeabi_dadd adddf3 > > -1: do_push {r4, r5, lr} > +1: do_push {r4, r5, lr} @ sp -= 12 > + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 > + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 8 > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset lr, 8 > > @ Look for zeroes, equal values, INF, or NAN. > shift1 lsl, r4, xh, #1 > @@ -148,6 +159,11 @@ ARM_FUNC_ALIAS aeabi_dadd adddf3 > @ Since this is not common case, rescale them off line. > teq r4, r5 > beq LSYM(Lad_d) > + > +@ CFI note: we're lucky that the branches to Lad_* that appear after this function > +@ have a CFI state that's exactly the same as the one we're in at this > +@ point. Otherwise the CFI would change to a different state after the branch, > +@ which would be disastrous for backtracing. > LSYM(Lad_x): > > @ Compensate for the exponent overlapping the mantissa MSB added later > @@ -413,6 +429,7 @@ LSYM(Lad_i): > orrne xh, xh, #0x00080000 @ quiet NAN > RETLDM "r4, r5" > > + CFI_END_FUNCTION > FUNC_END aeabi_dsub > FUNC_END subdf3 > FUNC_END aeabi_dadd > @@ -420,12 +437,19 @@ LSYM(Lad_i): > > ARM_FUNC_START floatunsidf > ARM_FUNC_ALIAS aeabi_ui2d floatunsidf > + CFI_START_FUNCTION > > teq r0, #0 > do_it eq, t > moveq r1, #0 > RETc(eq) > - do_push {r4, r5, lr} > + > + do_push {r4, r5, lr} @ sp -= 12 > + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 > + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset lr, 8 > + > mov r4, #0x400 @ initial exponent > add r4, r4, #(52-1 - 1) > mov r5, #0 @ sign bit is 0 > @@ -435,17 +459,25 @@ ARM_FUNC_ALIAS aeabi_ui2d floatunsidf > mov xh, #0 > b LSYM(Lad_l) > > + CFI_END_FUNCTION > FUNC_END aeabi_ui2d > FUNC_END floatunsidf > > ARM_FUNC_START floatsidf > ARM_FUNC_ALIAS aeabi_i2d floatsidf > + CFI_START_FUNCTION > > teq r0, #0 > do_it eq, t > moveq r1, #0 > RETc(eq) > - do_push {r4, r5, lr} > + > + do_push {r4, r5, lr} @ sp -= 12 > + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 > + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset lr, 8 > + > mov r4, #0x400 @ initial exponent > add r4, r4, #(52-1 - 1) > ands r5, r0, #0x80000000 @ sign bit in r5 > @@ -457,11 +489,13 @@ ARM_FUNC_ALIAS aeabi_i2d floatsidf > mov xh, #0 > b LSYM(Lad_l) > > + CFI_END_FUNCTION > FUNC_END aeabi_i2d > FUNC_END floatsidf > > ARM_FUNC_START extendsfdf2 > ARM_FUNC_ALIAS aeabi_f2d extendsfdf2 > + CFI_START_FUNCTION > > movs r2, r0, lsl #1 @ toss sign bit > mov xh, r2, asr #3 @ stretch exponent > @@ -480,34 +514,54 @@ ARM_FUNC_ALIAS aeabi_f2d extendsfdf2 > > @ value was denormalized. We can normalize it now. > do_push {r4, r5, lr} > + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 > + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset lr, 8 > + > mov r4, #0x380 @ setup corresponding exponent > and r5, xh, #0x80000000 @ move sign bit in r5 > bic xh, xh, #0x80000000 > b LSYM(Lad_l) > > + CFI_END_FUNCTION > FUNC_END aeabi_f2d > FUNC_END extendsfdf2 > > ARM_FUNC_START floatundidf > ARM_FUNC_ALIAS aeabi_ul2d floatundidf > + CFI_START_FUNCTION > + .cfi_remember_state @ Save the current CFA state. > > orrs r2, r0, r1 > do_it eq > RETc(eq) > > - do_push {r4, r5, lr} > + do_push {r4, r5, lr} @ sp -= 12 > + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 > + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8 > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset lr, 8 > > mov r5, #0 > b 2f > > ARM_FUNC_START floatdidf > ARM_FUNC_ALIAS aeabi_l2d floatdidf > + .cfi_restore_state > + @ Restore the CFI state we saved above. If we didn't do this then the > + @ following instructions would have the CFI state that was set by the > + @ offset adjustments made in floatundidf. > > orrs r2, r0, r1 > do_it eq > RETc(eq) > > - do_push {r4, r5, lr} > + do_push {r4, r5, lr} @ sp -= 12 > + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 > + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 8 > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset lr, 8 > > ands r5, ah, #0x80000000 @ sign bit in r5 > bpl 2f > @@ -550,6 +604,7 @@ ARM_FUNC_ALIAS aeabi_l2d floatdidf > add r4, r4, r2 > b LSYM(Lad_p) > > + CFI_END_FUNCTION > FUNC_END floatdidf > FUNC_END aeabi_l2d > FUNC_END floatundidf > @@ -561,7 +616,14 @@ ARM_FUNC_ALIAS aeabi_l2d floatdidf > > ARM_FUNC_START muldf3 > ARM_FUNC_ALIAS aeabi_dmul muldf3 > - do_push {r4, r5, r6, lr} > + CFI_START_FUNCTION > + > + do_push {r4, r5, r6, lr} @ sp -= 16 > + .cfi_adjust_cfa_offset 16 @ CFA is now sp + previousOffset + 16 > + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 12. > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset r6, 8 > + .cfi_rel_offset lr, 12 > > @ Mask out exponents, trap any zero/denormal/INF/NAN. > mov ip, #0xff > @@ -596,7 +658,16 @@ ARM_FUNC_ALIAS aeabi_dmul muldf3 > and r6, r6, #0x80000000 > > @ Well, no way to make it shorter without the umull instruction. > - stmfd sp!, {r6, r7, r8, r9, sl, fp} > + stmfd sp!, {r6, r7, r8, r9, sl, fp} @ sp -= 24 > + .cfi_remember_state @ Save the current CFI state. > + .cfi_adjust_cfa_offset 24 @ CFA is now sp + previousOffset + 24. > + .cfi_rel_offset r6, 0 @ Registers are saved from sp to sp + 20. > + .cfi_rel_offset r7, 4 > + .cfi_rel_offset r8, 8 > + .cfi_rel_offset r9, 12 > + .cfi_rel_offset sl, 16 > + .cfi_rel_offset fp, 20 > + > mov r7, xl, lsr #16 > mov r8, yl, lsr #16 > mov r9, xh, lsr #16 > @@ -648,8 +719,8 @@ ARM_FUNC_ALIAS aeabi_dmul muldf3 > mul fp, xh, yh > adcs r5, r5, fp > adc r6, r6, #0 > - ldmfd sp!, {yl, r7, r8, r9, sl, fp} > - > + ldmfd sp!, {yl, r7, r8, r9, sl, fp} @ sp += 24 > + .cfi_restore_state @ Restore the previous CFI state. > #else > > @ Here is the actual multiplication. > @@ -715,7 +786,6 @@ LSYM(Lml_1): > orr xh, xh, #0x00100000 > mov lr, #0 > subs r4, r4, #1 > - > LSYM(Lml_u): > @ Overflow? > bgt LSYM(Lml_o) > @@ -863,13 +933,20 @@ LSYM(Lml_n): > orr xh, xh, #0x00f80000 > RETLDM "r4, r5, r6" > > + CFI_END_FUNCTION > FUNC_END aeabi_dmul > FUNC_END muldf3 > > ARM_FUNC_START divdf3 > ARM_FUNC_ALIAS aeabi_ddiv divdf3 > + CFI_START_FUNCTION > > do_push {r4, r5, r6, lr} > + .cfi_adjust_cfa_offset 16 > + .cfi_rel_offset r4, 0 > + .cfi_rel_offset r5, 4 > + .cfi_rel_offset r6, 8 > + .cfi_rel_offset lr, 12 > > @ Mask out exponents, trap any zero/denormal/INF/NAN. > mov ip, #0xff > @@ -1052,6 +1129,7 @@ LSYM(Ldv_s): > bne LSYM(Lml_z) @ 0 / <non_zero> -> 0 > b LSYM(Lml_n) @ 0 / 0 -> NAN > > + CFI_END_FUNCTION > FUNC_END aeabi_ddiv > FUNC_END divdf3 > > @@ -1063,6 +1141,7 @@ LSYM(Ldv_s): > > ARM_FUNC_START gtdf2 > ARM_FUNC_ALIAS gedf2 gtdf2 > + CFI_START_FUNCTION > mov ip, #-1 > b 1f > > @@ -1077,6 +1156,10 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 > mov ip, #1 @ how should we specify unordered here? > > 1: str ip, [sp, #-4]! > + .cfi_adjust_cfa_offset 4 @ CFA is now sp + previousOffset + 4. > + @ We're not adding CFI for ip as it's pushed into the stack only because > + @ it may be popped off later as a return value (i.e. we're not preserving > + @ it anyways). > > @ Trap any INF/NAN first. > mov ip, xh, lsl #1 > @@ -1085,10 +1168,18 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 > do_it ne > COND(mvn,s,ne) ip, ip, asr #21 > beq 3f > + .cfi_remember_state > + @ Save the current CFI state. This is done because the branch is conditional, > + @ and if we don't take it we'll issue a .cfi_adjust_cfa_offset and return. > + @ If we do take it, however, the .cfi_adjust_cfa_offset from the non-branch > + @ code will affect the branch code as well. To avoid this we'll restore > + @ the current state before executing the branch code. > > @ Test for equality. > @ Note that 0.0 is equal to -0.0. > 2: add sp, sp, #4 > + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. > + > orrs ip, xl, xh, lsl #1 @ if x == 0.0 or -0.0 > do_it eq, e > COND(orr,s,eq) ip, yl, yh, lsl #1 @ and y == 0.0 or -0.0 > @@ -1117,8 +1208,13 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 > orr r0, r0, #1 > RET > > - @ Look for a NAN. > -3: mov ip, xh, lsl #1 > +3: @ Look for a NAN. > + > + @ Restore the previous CFI state (i.e. keep the CFI state as it was > + @ before the branch). > + .cfi_restore_state > + > + mov ip, xh, lsl #1 > mvns ip, ip, asr #21 > bne 4f > orrs ip, xl, xh, lsl #12 > @@ -1128,9 +1224,13 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 > bne 2b > orrs ip, yl, yh, lsl #12 > beq 2b @ y is not NAN > + > 5: ldr r0, [sp], #4 @ unordered return code > + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. > + > RET > > + CFI_END_FUNCTION > FUNC_END gedf2 > FUNC_END gtdf2 > FUNC_END ledf2 > @@ -1140,6 +1240,7 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 > FUNC_END cmpdf2 > > ARM_FUNC_START aeabi_cdrcmple > + CFI_START_FUNCTION > > mov ip, r0 > mov r0, r2 > @@ -1149,12 +1250,16 @@ ARM_FUNC_START aeabi_cdrcmple > mov r3, ip > b 6f > > -ARM_FUNC_START aeabi_cdcmpeq > +; ARM_FUNC_START aeabi_cdcmpeq > ARM_FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq > > @ The status-returning routines are required to preserve all > @ registers except ip, lr, and cpsr. > 6: do_push {r0, lr} > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8. > + .cfi_rel_offset r0, 0 @ Previous r0 is saved at sp. > + .cfi_rel_offset lr, 4 @ Previous lr is saved at sp + 4. > + > ARM_CALL cmpdf2 > @ Set the Z flag correctly, and the C flag unconditionally. > cmp r0, #0 > @@ -1162,59 +1267,86 @@ ARM_FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq > @ that the first operand was smaller than the second. > do_it mi > cmnmi r0, #0 > + > RETLDM "r0" > > + CFI_END_FUNCTION > FUNC_END aeabi_cdcmple > FUNC_END aeabi_cdcmpeq > FUNC_END aeabi_cdrcmple > > ARM_FUNC_START aeabi_dcmpeq > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cdcmple > do_it eq, e > moveq r0, #1 @ Equal to. > movne r0, #0 @ Less than, greater than, or unordered. > + > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_dcmpeq > > ARM_FUNC_START aeabi_dcmplt > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cdcmple > do_it cc, e > movcc r0, #1 @ Less than. > movcs r0, #0 @ Equal to, greater than, or unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_dcmplt > > ARM_FUNC_START aeabi_dcmple > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cdcmple > do_it ls, e > movls r0, #1 @ Less than or equal to. > movhi r0, #0 @ Greater than or unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_dcmple > > ARM_FUNC_START aeabi_dcmpge > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cdrcmple > do_it ls, e > movls r0, #1 @ Operand 2 is less than or equal to operand 1. > movhi r0, #0 @ Operand 2 greater than operand 1, or unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_dcmpge > > ARM_FUNC_START aeabi_dcmpgt > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cdrcmple > do_it cc, e > movcc r0, #1 @ Operand 2 is less than operand 1. > @@ -1222,6 +1354,7 @@ ARM_FUNC_START aeabi_dcmpgt > @ or they are unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_dcmpgt > > #endif /* L_cmpdf2 */ > @@ -1230,6 +1363,7 @@ ARM_FUNC_START aeabi_dcmpgt > > ARM_FUNC_START unorddf2 > ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 > + .cfi_startproc > > mov ip, xh, lsl #1 > mvns ip, ip, asr #21 > @@ -1247,6 +1381,7 @@ ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 > 3: mov r0, #1 @ arguments are unordered. > RET > > + .cfi_endproc > FUNC_END aeabi_dcmpun > FUNC_END unorddf2 > > @@ -1256,6 +1391,7 @@ ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 > > ARM_FUNC_START fixdfsi > ARM_FUNC_ALIAS aeabi_d2iz fixdfsi > + CFI_START_FUNCTION > > @ check exponent range. > mov r2, xh, lsl #1 > @@ -1289,6 +1425,7 @@ ARM_FUNC_ALIAS aeabi_d2iz fixdfsi > 4: mov r0, #0 @ How should we convert NAN? > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_d2iz > FUNC_END fixdfsi > > @@ -1298,6 +1435,7 @@ ARM_FUNC_ALIAS aeabi_d2iz fixdfsi > > ARM_FUNC_START fixunsdfsi > ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi > + CFI_START_FUNCTION > > @ check exponent range. > movs r2, xh, lsl #1 > @@ -1327,6 +1465,7 @@ ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi > 4: mov r0, #0 @ How should we convert NAN? > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_d2uiz > FUNC_END fixunsdfsi > > @@ -1336,6 +1475,7 @@ ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi > > ARM_FUNC_START truncdfsf2 > ARM_FUNC_ALIAS aeabi_d2f truncdfsf2 > + CFI_START_FUNCTION > > @ check exponent range. > mov r2, xh, lsl #1 > @@ -1400,6 +1540,7 @@ ARM_FUNC_ALIAS aeabi_d2f truncdfsf2 > orr r0, r0, #0x00800000 > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_d2f > FUNC_END truncdfsf2 > > diff --git a/libgcc/config/arm/ieee754-sf.S b/libgcc/config/arm/ieee754-sf.S > index 3e76241..a93d40a 100644 > --- a/libgcc/config/arm/ieee754-sf.S > +++ b/libgcc/config/arm/ieee754-sf.S > @@ -31,16 +31,21 @@ > * Only the default rounding mode is intended for best performances. > * Exceptions aren't supported yet, but that can be added quite easily > * if necessary without impacting performances. > + * > + * In the CFI related comments, 'previousOffset' refers to the previous offset > + * from sp used to compute the CFA. > */ > > #ifdef L_arm_negsf2 > > ARM_FUNC_START negsf2 > ARM_FUNC_ALIAS aeabi_fneg negsf2 > + CFI_START_FUNCTION > > eor r0, r0, #0x80000000 @ flip sign bit > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_fneg > FUNC_END negsf2 > > @@ -49,6 +54,7 @@ ARM_FUNC_ALIAS aeabi_fneg negsf2 > #ifdef L_arm_addsubsf3 > > ARM_FUNC_START aeabi_frsub > + CFI_START_FUNCTION > > eor r0, r0, #0x80000000 @ flip sign bit of first arg > b 1f > @@ -284,6 +290,7 @@ LSYM(Lad_i): > orrne r0, r0, #0x00400000 @ quiet NAN > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_frsub > FUNC_END aeabi_fadd > FUNC_END addsf3 > @@ -292,6 +299,7 @@ LSYM(Lad_i): > > ARM_FUNC_START floatunsisf > ARM_FUNC_ALIAS aeabi_ui2f floatunsisf > + CFI_START_FUNCTION > > mov r3, #0 > b 1f > @@ -316,6 +324,7 @@ ARM_FUNC_ALIAS aeabi_i2f floatsisf > mov al, #0 > b 2f > > + CFI_END_FUNCTION > FUNC_END aeabi_i2f > FUNC_END floatsisf > FUNC_END aeabi_ui2f > @@ -323,6 +332,7 @@ ARM_FUNC_ALIAS aeabi_i2f floatsisf > > ARM_FUNC_START floatundisf > ARM_FUNC_ALIAS aeabi_ul2f floatundisf > + CFI_START_FUNCTION > > orrs r2, r0, r1 > do_it eq > @@ -409,6 +419,7 @@ ARM_FUNC_ALIAS aeabi_l2f floatdisf > biceq r0, r0, ip, lsr #31 > RET > > + CFI_END_FUNCTION > FUNC_END floatdisf > FUNC_END aeabi_l2f > FUNC_END floatundisf > @@ -420,6 +431,7 @@ ARM_FUNC_ALIAS aeabi_l2f floatdisf > > ARM_FUNC_START mulsf3 > ARM_FUNC_ALIAS aeabi_fmul mulsf3 > + CFI_START_FUNCTION > > @ Mask out exponents, trap any zero/denormal/INF/NAN. > mov ip, #0xff > @@ -454,7 +466,13 @@ LSYM(Lml_x): > and r3, ip, #0x80000000 > > @ Well, no way to make it shorter without the umull instruction. > - do_push {r3, r4, r5} > + do_push {r3, r4, r5} @ sp -= 12 > + .cfi_remember_state @ Save the current CFI state > + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 > + .cfi_rel_offset r3, 0 @ Registers are saved from sp to sp + 8 > + .cfi_rel_offset r4, 4 > + .cfi_rel_offset r5, 8 > + > mov r4, r0, lsr #16 > mov r5, r1, lsr #16 > bic r0, r0, r4, lsl #16 > @@ -465,7 +483,8 @@ LSYM(Lml_x): > mla r0, r4, r1, r0 > adds r3, r3, r0, lsl #16 > adc r1, ip, r0, lsr #16 > - do_pop {r0, r4, r5} > + do_pop {r0, r4, r5} @ sp += 12 > + .cfi_restore_state @ Restore the previous CFI state > > #else > > @@ -618,11 +637,13 @@ LSYM(Lml_n): > orr r0, r0, #0x00c00000 > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_fmul > FUNC_END mulsf3 > > ARM_FUNC_START divsf3 > ARM_FUNC_ALIAS aeabi_fdiv divsf3 > + CFI_START_FUNCTION > > @ Mask out exponents, trap any zero/denormal/INF/NAN. > mov ip, #0xff > @@ -758,6 +779,7 @@ LSYM(Ldv_s): > bne LSYM(Lml_z) @ 0 / <non_zero> -> 0 > b LSYM(Lml_n) @ 0 / 0 -> NAN > > + CFI_END_FUNCTION > FUNC_END aeabi_fdiv > FUNC_END divsf3 > > @@ -782,6 +804,7 @@ LSYM(Ldv_s): > > ARM_FUNC_START gtsf2 > ARM_FUNC_ALIAS gesf2 gtsf2 > + CFI_START_FUNCTION > mov ip, #-1 > b 1f > > @@ -796,6 +819,10 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 > mov ip, #1 @ how should we specify unordered here? > > 1: str ip, [sp, #-4]! > + .cfi_adjust_cfa_offset 4 @ CFA is now sp + previousOffset + 4. > + @ We're not adding CFI for ip as it's pushed into the stack only because > + @ it may be popped off later as a return value (i.e. we're not preserving > + @ it anyways). > > @ Trap any INF/NAN first. > mov r2, r0, lsl #1 > @@ -804,10 +831,18 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 > do_it ne > COND(mvn,s,ne) ip, r3, asr #24 > beq 3f > + .cfi_remember_state > + @ Save the current CFI state. This is done because the branch is conditional, > + @ and if we don't take it we'll issue a .cfi_adjust_cfa_offset and return. > + @ If we do take it, however, the .cfi_adjust_cfa_offset from the non-branch > + @ code will affect the branch code as well. To avoid this we'll restore > + @ the current state before executing the branch code. > > @ Compare values. > @ Note that 0.0 is equal to -0.0. > 2: add sp, sp, #4 > + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. > + > orrs ip, r2, r3, lsr #1 @ test if both are 0, clear C flag > do_it ne > teqne r0, r1 @ if not 0 compare sign > @@ -823,8 +858,13 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 > orrne r0, r0, #1 > RET > > - @ Look for a NAN. > -3: mvns ip, r2, asr #24 > +3: @ Look for a NAN. > + > + @ Restore the previous CFI state (i.e. keep the CFI state as it was > + @ before the branch). > + .cfi_restore_state > + > + mvns ip, r2, asr #24 > bne 4f > movs ip, r0, lsl #9 > bne 5f @ r0 is NAN > @@ -832,9 +872,12 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 > bne 2b > movs ip, r1, lsl #9 > beq 2b @ r1 is not NAN > + > 5: ldr r0, [sp], #4 @ return unordered code. > + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. > RET > > + CFI_END_FUNCTION > FUNC_END gesf2 > FUNC_END gtsf2 > FUNC_END lesf2 > @@ -844,6 +887,7 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 > FUNC_END cmpsf2 > > ARM_FUNC_START aeabi_cfrcmple > + CFI_START_FUNCTION > > mov ip, r0 > mov r0, r1 > @@ -856,6 +900,13 @@ ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq > @ The status-returning routines are required to preserve all > @ registers except ip, lr, and cpsr. > 6: do_push {r0, r1, r2, r3, lr} > + .cfi_adjust_cfa_offset 20 @ CFA is at sp + previousOffset + 20 > + .cfi_rel_offset r0, 0 @ Registers are saved from sp to sp + 16 > + .cfi_rel_offset r1, 4 > + .cfi_rel_offset r2, 8 > + .cfi_rel_offset r3, 12 > + .cfi_rel_offset lr, 16 > + > ARM_CALL cmpsf2 > @ Set the Z flag correctly, and the C flag unconditionally. > cmp r0, #0 > @@ -865,57 +916,82 @@ ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq > cmnmi r0, #0 > RETLDM "r0, r1, r2, r3" > > + CFI_END_FUNCTION > FUNC_END aeabi_cfcmple > FUNC_END aeabi_cfcmpeq > FUNC_END aeabi_cfrcmple > > ARM_FUNC_START aeabi_fcmpeq > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cfcmple > do_it eq, e > moveq r0, #1 @ Equal to. > movne r0, #0 @ Less than, greater than, or unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_fcmpeq > > ARM_FUNC_START aeabi_fcmplt > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cfcmple > do_it cc, e > movcc r0, #1 @ Less than. > movcs r0, #0 @ Equal to, greater than, or unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_fcmplt > > ARM_FUNC_START aeabi_fcmple > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cfcmple > do_it ls, e > movls r0, #1 @ Less than or equal to. > movhi r0, #0 @ Greater than or unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_fcmple > > ARM_FUNC_START aeabi_fcmpge > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cfrcmple > do_it ls, e > movls r0, #1 @ Operand 2 is less than or equal to operand 1. > movhi r0, #0 @ Operand 2 greater than operand 1, or unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_fcmpge > > ARM_FUNC_START aeabi_fcmpgt > + CFI_START_FUNCTION > + > + str lr, [sp, #-8]! @ sp -= 8 > + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 > + .cfi_rel_offset lr, 0 @ lr is at sp > > - str lr, [sp, #-8]! > ARM_CALL aeabi_cfrcmple > do_it cc, e > movcc r0, #1 @ Operand 2 is less than operand 1. > @@ -923,6 +999,7 @@ ARM_FUNC_START aeabi_fcmpgt > @ or they are unordered. > RETLDM > > + CFI_END_FUNCTION > FUNC_END aeabi_fcmpgt > > #endif /* L_cmpsf2 */ > @@ -931,6 +1008,7 @@ ARM_FUNC_START aeabi_fcmpgt > > ARM_FUNC_START unordsf2 > ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 > + CFI_START_FUNCTION > > mov r2, r0, lsl #1 > mov r3, r1, lsl #1 > @@ -947,6 +1025,7 @@ ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 > 3: mov r0, #1 @ arguments are unordered. > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_fcmpun > FUNC_END unordsf2 > > @@ -956,6 +1035,7 @@ ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 > > ARM_FUNC_START fixsfsi > ARM_FUNC_ALIAS aeabi_f2iz fixsfsi > + CFI_START_FUNCTION > > @ check exponent range. > mov r2, r0, lsl #1 > @@ -989,6 +1069,7 @@ ARM_FUNC_ALIAS aeabi_f2iz fixsfsi > 4: mov r0, #0 @ What should we convert NAN to? > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_f2iz > FUNC_END fixsfsi > > @@ -998,6 +1079,7 @@ ARM_FUNC_ALIAS aeabi_f2iz fixsfsi > > ARM_FUNC_START fixunssfsi > ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi > + CFI_START_FUNCTION > > @ check exponent range. > movs r2, r0, lsl #1 > @@ -1027,6 +1109,7 @@ ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi > 4: mov r0, #0 @ What should we convert NAN to? > RET > > + CFI_END_FUNCTION > FUNC_END aeabi_f2uiz > FUNC_END fixunssfsi > > diff --git a/libgcc/config/arm/lib1funcs.S b/libgcc/config/arm/lib1funcs.S > index d2d0d20..4b63924 100644 > --- a/libgcc/config/arm/lib1funcs.S > +++ b/libgcc/config/arm/lib1funcs.S > @@ -1965,6 +1965,16 @@ LSYM(Lchange_\register): > > #endif /* Arch supports thumb. */ > > +.macro CFI_START_FUNCTION > + .cfi_startproc > + .cfi_remember_state > +.endm > + > +.macro CFI_END_FUNCTION > + .cfi_restore_state > + .cfi_endproc > +.endm > + > #ifndef __symbian__ > #ifndef __ARM_ARCH_6M__ > #include "ieee754-df.S" ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM 2015-04-28 16:22 ` Ramana Radhakrishnan @ 2015-04-28 17:10 ` Martin Galvan 2015-05-04 20:51 ` Martin Galvan 0 siblings, 1 reply; 6+ messages in thread From: Martin Galvan @ 2015-04-28 17:10 UTC (permalink / raw) To: ramrad01; +Cc: gcc-patches Thanks a lot. I don't have write access to the repository, could you commit this for me? On Tue, Apr 28, 2015 at 1:21 PM, Ramana Radhakrishnan <ramana.gcc@googlemail.com> wrote: > On Tue, Apr 28, 2015 at 4:19 PM, Martin Galvan > <martin.galvan@tallertechnologies.com> wrote: >> This patch adds CFI directives to the soft floating point support code for ARM. >> >> Previously, if we tried to do a backtrace from that code in a debug session we'd >> get something like this: >> >> (gdb) bt >> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1082 >> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1158 >> #2 0xf5c28f5c in ?? () >> Backtrace stopped: previous frame identical to this frame (corrupt stack?) >> >> Now we'll get something like this: >> >> (gdb) bt >> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1156 >> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1263 >> #2 0x00000dc8 in __aeabi_dcmpeq () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1285 >> #3 0x00000504 in main () >> >> I have a company-wide copyright assignment. I don't have commit access, though, so it would be great if anyone could commit this for me. >> >> Thanks a lot! >> > > this is OK , thanks. Sorry about the delay in reviewing this. > > Ramana > >> libgcc/ChangeLog: >> 2015-04-23 Martin Galvan <martin.galvan@tallertechnologies.com> >> >> * config/arm/lib1funcs.S (CFI_START_FUNCTION, CFI_END_FUNCTION): >> New macros. >> * config/arm/ieee754-df.S: Add CFI directives. >> * config/arm/ieee754-sf.S: Add CFI directives. >> >> --- >> libgcc/config/arm/ieee754-df.S | 177 ++- >> libgcc/config/arm/ieee754-sf.S | 1727 ++++++++++++++------------- >> libgcc/config/arm/lib1funcs.S | 10 + >> 3 files changed, 1074 insertions(+), 840 deletions(-) >> >> diff --git a/libgcc/config/arm/ieee754-df.S b/libgcc/config/arm/ieee754-df.S >> index f75630b..d1f9066 100644 >> --- a/libgcc/config/arm/ieee754-df.S >> +++ b/libgcc/config/arm/ieee754-df.S >> @@ -33,8 +33,12 @@ >> * Only the default rounding mode is intended for best performances. >> * Exceptions aren't supported yet, but that can be added quite easily >> * if necessary without impacting performances. >> + * >> + * In the CFI related comments, 'previousOffset' refers to the previous offset >> + * from sp used to compute the CFA. >> */ >> >> + .cfi_sections .debug_frame >> >> #ifndef __ARMEB__ >> #define xl r0 >> @@ -53,11 +57,13 @@ >> >> ARM_FUNC_START negdf2 >> ARM_FUNC_ALIAS aeabi_dneg negdf2 >> + CFI_START_FUNCTION >> >> @ flip sign bit >> eor xh, xh, #0x80000000 >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dneg >> FUNC_END negdf2 >> >> @@ -66,6 +72,7 @@ ARM_FUNC_ALIAS aeabi_dneg negdf2 >> #ifdef L_arm_addsubdf3 >> >> ARM_FUNC_START aeabi_drsub >> + CFI_START_FUNCTION >> >> eor xh, xh, #0x80000000 @ flip sign bit of first arg >> b 1f >> @@ -81,7 +88,11 @@ ARM_FUNC_ALIAS aeabi_dsub subdf3 >> ARM_FUNC_START adddf3 >> ARM_FUNC_ALIAS aeabi_dadd adddf3 >> >> -1: do_push {r4, r5, lr} >> +1: do_push {r4, r5, lr} @ sp -= 12 >> + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 >> + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 8 >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset lr, 8 >> >> @ Look for zeroes, equal values, INF, or NAN. >> shift1 lsl, r4, xh, #1 >> @@ -148,6 +159,11 @@ ARM_FUNC_ALIAS aeabi_dadd adddf3 >> @ Since this is not common case, rescale them off line. >> teq r4, r5 >> beq LSYM(Lad_d) >> + >> +@ CFI note: we're lucky that the branches to Lad_* that appear after this function >> +@ have a CFI state that's exactly the same as the one we're in at this >> +@ point. Otherwise the CFI would change to a different state after the branch, >> +@ which would be disastrous for backtracing. >> LSYM(Lad_x): >> >> @ Compensate for the exponent overlapping the mantissa MSB added later >> @@ -413,6 +429,7 @@ LSYM(Lad_i): >> orrne xh, xh, #0x00080000 @ quiet NAN >> RETLDM "r4, r5" >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dsub >> FUNC_END subdf3 >> FUNC_END aeabi_dadd >> @@ -420,12 +437,19 @@ LSYM(Lad_i): >> >> ARM_FUNC_START floatunsidf >> ARM_FUNC_ALIAS aeabi_ui2d floatunsidf >> + CFI_START_FUNCTION >> >> teq r0, #0 >> do_it eq, t >> moveq r1, #0 >> RETc(eq) >> - do_push {r4, r5, lr} >> + >> + do_push {r4, r5, lr} @ sp -= 12 >> + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 >> + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset lr, 8 >> + >> mov r4, #0x400 @ initial exponent >> add r4, r4, #(52-1 - 1) >> mov r5, #0 @ sign bit is 0 >> @@ -435,17 +459,25 @@ ARM_FUNC_ALIAS aeabi_ui2d floatunsidf >> mov xh, #0 >> b LSYM(Lad_l) >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_ui2d >> FUNC_END floatunsidf >> >> ARM_FUNC_START floatsidf >> ARM_FUNC_ALIAS aeabi_i2d floatsidf >> + CFI_START_FUNCTION >> >> teq r0, #0 >> do_it eq, t >> moveq r1, #0 >> RETc(eq) >> - do_push {r4, r5, lr} >> + >> + do_push {r4, r5, lr} @ sp -= 12 >> + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 >> + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset lr, 8 >> + >> mov r4, #0x400 @ initial exponent >> add r4, r4, #(52-1 - 1) >> ands r5, r0, #0x80000000 @ sign bit in r5 >> @@ -457,11 +489,13 @@ ARM_FUNC_ALIAS aeabi_i2d floatsidf >> mov xh, #0 >> b LSYM(Lad_l) >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_i2d >> FUNC_END floatsidf >> >> ARM_FUNC_START extendsfdf2 >> ARM_FUNC_ALIAS aeabi_f2d extendsfdf2 >> + CFI_START_FUNCTION >> >> movs r2, r0, lsl #1 @ toss sign bit >> mov xh, r2, asr #3 @ stretch exponent >> @@ -480,34 +514,54 @@ ARM_FUNC_ALIAS aeabi_f2d extendsfdf2 >> >> @ value was denormalized. We can normalize it now. >> do_push {r4, r5, lr} >> + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 >> + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8. >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset lr, 8 >> + >> mov r4, #0x380 @ setup corresponding exponent >> and r5, xh, #0x80000000 @ move sign bit in r5 >> bic xh, xh, #0x80000000 >> b LSYM(Lad_l) >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_f2d >> FUNC_END extendsfdf2 >> >> ARM_FUNC_START floatundidf >> ARM_FUNC_ALIAS aeabi_ul2d floatundidf >> + CFI_START_FUNCTION >> + .cfi_remember_state @ Save the current CFA state. >> >> orrs r2, r0, r1 >> do_it eq >> RETc(eq) >> >> - do_push {r4, r5, lr} >> + do_push {r4, r5, lr} @ sp -= 12 >> + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 >> + .cfi_rel_offset r4, 0 @ Registers are saved from sp + 0 to sp + 8 >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset lr, 8 >> >> mov r5, #0 >> b 2f >> >> ARM_FUNC_START floatdidf >> ARM_FUNC_ALIAS aeabi_l2d floatdidf >> + .cfi_restore_state >> + @ Restore the CFI state we saved above. If we didn't do this then the >> + @ following instructions would have the CFI state that was set by the >> + @ offset adjustments made in floatundidf. >> >> orrs r2, r0, r1 >> do_it eq >> RETc(eq) >> >> - do_push {r4, r5, lr} >> + do_push {r4, r5, lr} @ sp -= 12 >> + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 >> + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 8 >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset lr, 8 >> >> ands r5, ah, #0x80000000 @ sign bit in r5 >> bpl 2f >> @@ -550,6 +604,7 @@ ARM_FUNC_ALIAS aeabi_l2d floatdidf >> add r4, r4, r2 >> b LSYM(Lad_p) >> >> + CFI_END_FUNCTION >> FUNC_END floatdidf >> FUNC_END aeabi_l2d >> FUNC_END floatundidf >> @@ -561,7 +616,14 @@ ARM_FUNC_ALIAS aeabi_l2d floatdidf >> >> ARM_FUNC_START muldf3 >> ARM_FUNC_ALIAS aeabi_dmul muldf3 >> - do_push {r4, r5, r6, lr} >> + CFI_START_FUNCTION >> + >> + do_push {r4, r5, r6, lr} @ sp -= 16 >> + .cfi_adjust_cfa_offset 16 @ CFA is now sp + previousOffset + 16 >> + .cfi_rel_offset r4, 0 @ Registers are saved from sp to sp + 12. >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset r6, 8 >> + .cfi_rel_offset lr, 12 >> >> @ Mask out exponents, trap any zero/denormal/INF/NAN. >> mov ip, #0xff >> @@ -596,7 +658,16 @@ ARM_FUNC_ALIAS aeabi_dmul muldf3 >> and r6, r6, #0x80000000 >> >> @ Well, no way to make it shorter without the umull instruction. >> - stmfd sp!, {r6, r7, r8, r9, sl, fp} >> + stmfd sp!, {r6, r7, r8, r9, sl, fp} @ sp -= 24 >> + .cfi_remember_state @ Save the current CFI state. >> + .cfi_adjust_cfa_offset 24 @ CFA is now sp + previousOffset + 24. >> + .cfi_rel_offset r6, 0 @ Registers are saved from sp to sp + 20. >> + .cfi_rel_offset r7, 4 >> + .cfi_rel_offset r8, 8 >> + .cfi_rel_offset r9, 12 >> + .cfi_rel_offset sl, 16 >> + .cfi_rel_offset fp, 20 >> + >> mov r7, xl, lsr #16 >> mov r8, yl, lsr #16 >> mov r9, xh, lsr #16 >> @@ -648,8 +719,8 @@ ARM_FUNC_ALIAS aeabi_dmul muldf3 >> mul fp, xh, yh >> adcs r5, r5, fp >> adc r6, r6, #0 >> - ldmfd sp!, {yl, r7, r8, r9, sl, fp} >> - >> + ldmfd sp!, {yl, r7, r8, r9, sl, fp} @ sp += 24 >> + .cfi_restore_state @ Restore the previous CFI state. >> #else >> >> @ Here is the actual multiplication. >> @@ -715,7 +786,6 @@ LSYM(Lml_1): >> orr xh, xh, #0x00100000 >> mov lr, #0 >> subs r4, r4, #1 >> - >> LSYM(Lml_u): >> @ Overflow? >> bgt LSYM(Lml_o) >> @@ -863,13 +933,20 @@ LSYM(Lml_n): >> orr xh, xh, #0x00f80000 >> RETLDM "r4, r5, r6" >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dmul >> FUNC_END muldf3 >> >> ARM_FUNC_START divdf3 >> ARM_FUNC_ALIAS aeabi_ddiv divdf3 >> + CFI_START_FUNCTION >> >> do_push {r4, r5, r6, lr} >> + .cfi_adjust_cfa_offset 16 >> + .cfi_rel_offset r4, 0 >> + .cfi_rel_offset r5, 4 >> + .cfi_rel_offset r6, 8 >> + .cfi_rel_offset lr, 12 >> >> @ Mask out exponents, trap any zero/denormal/INF/NAN. >> mov ip, #0xff >> @@ -1052,6 +1129,7 @@ LSYM(Ldv_s): >> bne LSYM(Lml_z) @ 0 / <non_zero> -> 0 >> b LSYM(Lml_n) @ 0 / 0 -> NAN >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_ddiv >> FUNC_END divdf3 >> >> @@ -1063,6 +1141,7 @@ LSYM(Ldv_s): >> >> ARM_FUNC_START gtdf2 >> ARM_FUNC_ALIAS gedf2 gtdf2 >> + CFI_START_FUNCTION >> mov ip, #-1 >> b 1f >> >> @@ -1077,6 +1156,10 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 >> mov ip, #1 @ how should we specify unordered here? >> >> 1: str ip, [sp, #-4]! >> + .cfi_adjust_cfa_offset 4 @ CFA is now sp + previousOffset + 4. >> + @ We're not adding CFI for ip as it's pushed into the stack only because >> + @ it may be popped off later as a return value (i.e. we're not preserving >> + @ it anyways). >> >> @ Trap any INF/NAN first. >> mov ip, xh, lsl #1 >> @@ -1085,10 +1168,18 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 >> do_it ne >> COND(mvn,s,ne) ip, ip, asr #21 >> beq 3f >> + .cfi_remember_state >> + @ Save the current CFI state. This is done because the branch is conditional, >> + @ and if we don't take it we'll issue a .cfi_adjust_cfa_offset and return. >> + @ If we do take it, however, the .cfi_adjust_cfa_offset from the non-branch >> + @ code will affect the branch code as well. To avoid this we'll restore >> + @ the current state before executing the branch code. >> >> @ Test for equality. >> @ Note that 0.0 is equal to -0.0. >> 2: add sp, sp, #4 >> + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. >> + >> orrs ip, xl, xh, lsl #1 @ if x == 0.0 or -0.0 >> do_it eq, e >> COND(orr,s,eq) ip, yl, yh, lsl #1 @ and y == 0.0 or -0.0 >> @@ -1117,8 +1208,13 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 >> orr r0, r0, #1 >> RET >> >> - @ Look for a NAN. >> -3: mov ip, xh, lsl #1 >> +3: @ Look for a NAN. >> + >> + @ Restore the previous CFI state (i.e. keep the CFI state as it was >> + @ before the branch). >> + .cfi_restore_state >> + >> + mov ip, xh, lsl #1 >> mvns ip, ip, asr #21 >> bne 4f >> orrs ip, xl, xh, lsl #12 >> @@ -1128,9 +1224,13 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 >> bne 2b >> orrs ip, yl, yh, lsl #12 >> beq 2b @ y is not NAN >> + >> 5: ldr r0, [sp], #4 @ unordered return code >> + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. >> + >> RET >> >> + CFI_END_FUNCTION >> FUNC_END gedf2 >> FUNC_END gtdf2 >> FUNC_END ledf2 >> @@ -1140,6 +1240,7 @@ ARM_FUNC_ALIAS eqdf2 cmpdf2 >> FUNC_END cmpdf2 >> >> ARM_FUNC_START aeabi_cdrcmple >> + CFI_START_FUNCTION >> >> mov ip, r0 >> mov r0, r2 >> @@ -1149,12 +1250,16 @@ ARM_FUNC_START aeabi_cdrcmple >> mov r3, ip >> b 6f >> >> -ARM_FUNC_START aeabi_cdcmpeq >> +; ARM_FUNC_START aeabi_cdcmpeq >> ARM_FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq >> >> @ The status-returning routines are required to preserve all >> @ registers except ip, lr, and cpsr. >> 6: do_push {r0, lr} >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8. >> + .cfi_rel_offset r0, 0 @ Previous r0 is saved at sp. >> + .cfi_rel_offset lr, 4 @ Previous lr is saved at sp + 4. >> + >> ARM_CALL cmpdf2 >> @ Set the Z flag correctly, and the C flag unconditionally. >> cmp r0, #0 >> @@ -1162,59 +1267,86 @@ ARM_FUNC_ALIAS aeabi_cdcmple aeabi_cdcmpeq >> @ that the first operand was smaller than the second. >> do_it mi >> cmnmi r0, #0 >> + >> RETLDM "r0" >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_cdcmple >> FUNC_END aeabi_cdcmpeq >> FUNC_END aeabi_cdrcmple >> >> ARM_FUNC_START aeabi_dcmpeq >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cdcmple >> do_it eq, e >> moveq r0, #1 @ Equal to. >> movne r0, #0 @ Less than, greater than, or unordered. >> + >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dcmpeq >> >> ARM_FUNC_START aeabi_dcmplt >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cdcmple >> do_it cc, e >> movcc r0, #1 @ Less than. >> movcs r0, #0 @ Equal to, greater than, or unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dcmplt >> >> ARM_FUNC_START aeabi_dcmple >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cdcmple >> do_it ls, e >> movls r0, #1 @ Less than or equal to. >> movhi r0, #0 @ Greater than or unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dcmple >> >> ARM_FUNC_START aeabi_dcmpge >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cdrcmple >> do_it ls, e >> movls r0, #1 @ Operand 2 is less than or equal to operand 1. >> movhi r0, #0 @ Operand 2 greater than operand 1, or unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dcmpge >> >> ARM_FUNC_START aeabi_dcmpgt >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cdrcmple >> do_it cc, e >> movcc r0, #1 @ Operand 2 is less than operand 1. >> @@ -1222,6 +1354,7 @@ ARM_FUNC_START aeabi_dcmpgt >> @ or they are unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_dcmpgt >> >> #endif /* L_cmpdf2 */ >> @@ -1230,6 +1363,7 @@ ARM_FUNC_START aeabi_dcmpgt >> >> ARM_FUNC_START unorddf2 >> ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 >> + .cfi_startproc >> >> mov ip, xh, lsl #1 >> mvns ip, ip, asr #21 >> @@ -1247,6 +1381,7 @@ ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 >> 3: mov r0, #1 @ arguments are unordered. >> RET >> >> + .cfi_endproc >> FUNC_END aeabi_dcmpun >> FUNC_END unorddf2 >> >> @@ -1256,6 +1391,7 @@ ARM_FUNC_ALIAS aeabi_dcmpun unorddf2 >> >> ARM_FUNC_START fixdfsi >> ARM_FUNC_ALIAS aeabi_d2iz fixdfsi >> + CFI_START_FUNCTION >> >> @ check exponent range. >> mov r2, xh, lsl #1 >> @@ -1289,6 +1425,7 @@ ARM_FUNC_ALIAS aeabi_d2iz fixdfsi >> 4: mov r0, #0 @ How should we convert NAN? >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_d2iz >> FUNC_END fixdfsi >> >> @@ -1298,6 +1435,7 @@ ARM_FUNC_ALIAS aeabi_d2iz fixdfsi >> >> ARM_FUNC_START fixunsdfsi >> ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi >> + CFI_START_FUNCTION >> >> @ check exponent range. >> movs r2, xh, lsl #1 >> @@ -1327,6 +1465,7 @@ ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi >> 4: mov r0, #0 @ How should we convert NAN? >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_d2uiz >> FUNC_END fixunsdfsi >> >> @@ -1336,6 +1475,7 @@ ARM_FUNC_ALIAS aeabi_d2uiz fixunsdfsi >> >> ARM_FUNC_START truncdfsf2 >> ARM_FUNC_ALIAS aeabi_d2f truncdfsf2 >> + CFI_START_FUNCTION >> >> @ check exponent range. >> mov r2, xh, lsl #1 >> @@ -1400,6 +1540,7 @@ ARM_FUNC_ALIAS aeabi_d2f truncdfsf2 >> orr r0, r0, #0x00800000 >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_d2f >> FUNC_END truncdfsf2 >> >> diff --git a/libgcc/config/arm/ieee754-sf.S b/libgcc/config/arm/ieee754-sf.S >> index 3e76241..a93d40a 100644 >> --- a/libgcc/config/arm/ieee754-sf.S >> +++ b/libgcc/config/arm/ieee754-sf.S >> @@ -31,16 +31,21 @@ >> * Only the default rounding mode is intended for best performances. >> * Exceptions aren't supported yet, but that can be added quite easily >> * if necessary without impacting performances. >> + * >> + * In the CFI related comments, 'previousOffset' refers to the previous offset >> + * from sp used to compute the CFA. >> */ >> >> #ifdef L_arm_negsf2 >> >> ARM_FUNC_START negsf2 >> ARM_FUNC_ALIAS aeabi_fneg negsf2 >> + CFI_START_FUNCTION >> >> eor r0, r0, #0x80000000 @ flip sign bit >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fneg >> FUNC_END negsf2 >> >> @@ -49,6 +54,7 @@ ARM_FUNC_ALIAS aeabi_fneg negsf2 >> #ifdef L_arm_addsubsf3 >> >> ARM_FUNC_START aeabi_frsub >> + CFI_START_FUNCTION >> >> eor r0, r0, #0x80000000 @ flip sign bit of first arg >> b 1f >> @@ -284,6 +290,7 @@ LSYM(Lad_i): >> orrne r0, r0, #0x00400000 @ quiet NAN >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_frsub >> FUNC_END aeabi_fadd >> FUNC_END addsf3 >> @@ -292,6 +299,7 @@ LSYM(Lad_i): >> >> ARM_FUNC_START floatunsisf >> ARM_FUNC_ALIAS aeabi_ui2f floatunsisf >> + CFI_START_FUNCTION >> >> mov r3, #0 >> b 1f >> @@ -316,6 +324,7 @@ ARM_FUNC_ALIAS aeabi_i2f floatsisf >> mov al, #0 >> b 2f >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_i2f >> FUNC_END floatsisf >> FUNC_END aeabi_ui2f >> @@ -323,6 +332,7 @@ ARM_FUNC_ALIAS aeabi_i2f floatsisf >> >> ARM_FUNC_START floatundisf >> ARM_FUNC_ALIAS aeabi_ul2f floatundisf >> + CFI_START_FUNCTION >> >> orrs r2, r0, r1 >> do_it eq >> @@ -409,6 +419,7 @@ ARM_FUNC_ALIAS aeabi_l2f floatdisf >> biceq r0, r0, ip, lsr #31 >> RET >> >> + CFI_END_FUNCTION >> FUNC_END floatdisf >> FUNC_END aeabi_l2f >> FUNC_END floatundisf >> @@ -420,6 +431,7 @@ ARM_FUNC_ALIAS aeabi_l2f floatdisf >> >> ARM_FUNC_START mulsf3 >> ARM_FUNC_ALIAS aeabi_fmul mulsf3 >> + CFI_START_FUNCTION >> >> @ Mask out exponents, trap any zero/denormal/INF/NAN. >> mov ip, #0xff >> @@ -454,7 +466,13 @@ LSYM(Lml_x): >> and r3, ip, #0x80000000 >> >> @ Well, no way to make it shorter without the umull instruction. >> - do_push {r3, r4, r5} >> + do_push {r3, r4, r5} @ sp -= 12 >> + .cfi_remember_state @ Save the current CFI state >> + .cfi_adjust_cfa_offset 12 @ CFA is now sp + previousOffset + 12 >> + .cfi_rel_offset r3, 0 @ Registers are saved from sp to sp + 8 >> + .cfi_rel_offset r4, 4 >> + .cfi_rel_offset r5, 8 >> + >> mov r4, r0, lsr #16 >> mov r5, r1, lsr #16 >> bic r0, r0, r4, lsl #16 >> @@ -465,7 +483,8 @@ LSYM(Lml_x): >> mla r0, r4, r1, r0 >> adds r3, r3, r0, lsl #16 >> adc r1, ip, r0, lsr #16 >> - do_pop {r0, r4, r5} >> + do_pop {r0, r4, r5} @ sp += 12 >> + .cfi_restore_state @ Restore the previous CFI state >> >> #else >> >> @@ -618,11 +637,13 @@ LSYM(Lml_n): >> orr r0, r0, #0x00c00000 >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fmul >> FUNC_END mulsf3 >> >> ARM_FUNC_START divsf3 >> ARM_FUNC_ALIAS aeabi_fdiv divsf3 >> + CFI_START_FUNCTION >> >> @ Mask out exponents, trap any zero/denormal/INF/NAN. >> mov ip, #0xff >> @@ -758,6 +779,7 @@ LSYM(Ldv_s): >> bne LSYM(Lml_z) @ 0 / <non_zero> -> 0 >> b LSYM(Lml_n) @ 0 / 0 -> NAN >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fdiv >> FUNC_END divsf3 >> >> @@ -782,6 +804,7 @@ LSYM(Ldv_s): >> >> ARM_FUNC_START gtsf2 >> ARM_FUNC_ALIAS gesf2 gtsf2 >> + CFI_START_FUNCTION >> mov ip, #-1 >> b 1f >> >> @@ -796,6 +819,10 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 >> mov ip, #1 @ how should we specify unordered here? >> >> 1: str ip, [sp, #-4]! >> + .cfi_adjust_cfa_offset 4 @ CFA is now sp + previousOffset + 4. >> + @ We're not adding CFI for ip as it's pushed into the stack only because >> + @ it may be popped off later as a return value (i.e. we're not preserving >> + @ it anyways). >> >> @ Trap any INF/NAN first. >> mov r2, r0, lsl #1 >> @@ -804,10 +831,18 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 >> do_it ne >> COND(mvn,s,ne) ip, r3, asr #24 >> beq 3f >> + .cfi_remember_state >> + @ Save the current CFI state. This is done because the branch is conditional, >> + @ and if we don't take it we'll issue a .cfi_adjust_cfa_offset and return. >> + @ If we do take it, however, the .cfi_adjust_cfa_offset from the non-branch >> + @ code will affect the branch code as well. To avoid this we'll restore >> + @ the current state before executing the branch code. >> >> @ Compare values. >> @ Note that 0.0 is equal to -0.0. >> 2: add sp, sp, #4 >> + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. >> + >> orrs ip, r2, r3, lsr #1 @ test if both are 0, clear C flag >> do_it ne >> teqne r0, r1 @ if not 0 compare sign >> @@ -823,8 +858,13 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 >> orrne r0, r0, #1 >> RET >> >> - @ Look for a NAN. >> -3: mvns ip, r2, asr #24 >> +3: @ Look for a NAN. >> + >> + @ Restore the previous CFI state (i.e. keep the CFI state as it was >> + @ before the branch). >> + .cfi_restore_state >> + >> + mvns ip, r2, asr #24 >> bne 4f >> movs ip, r0, lsl #9 >> bne 5f @ r0 is NAN >> @@ -832,9 +872,12 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 >> bne 2b >> movs ip, r1, lsl #9 >> beq 2b @ r1 is not NAN >> + >> 5: ldr r0, [sp], #4 @ return unordered code. >> + .cfi_adjust_cfa_offset -4 @ CFA is now sp + previousOffset. >> RET >> >> + CFI_END_FUNCTION >> FUNC_END gesf2 >> FUNC_END gtsf2 >> FUNC_END lesf2 >> @@ -844,6 +887,7 @@ ARM_FUNC_ALIAS eqsf2 cmpsf2 >> FUNC_END cmpsf2 >> >> ARM_FUNC_START aeabi_cfrcmple >> + CFI_START_FUNCTION >> >> mov ip, r0 >> mov r0, r1 >> @@ -856,6 +900,13 @@ ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq >> @ The status-returning routines are required to preserve all >> @ registers except ip, lr, and cpsr. >> 6: do_push {r0, r1, r2, r3, lr} >> + .cfi_adjust_cfa_offset 20 @ CFA is at sp + previousOffset + 20 >> + .cfi_rel_offset r0, 0 @ Registers are saved from sp to sp + 16 >> + .cfi_rel_offset r1, 4 >> + .cfi_rel_offset r2, 8 >> + .cfi_rel_offset r3, 12 >> + .cfi_rel_offset lr, 16 >> + >> ARM_CALL cmpsf2 >> @ Set the Z flag correctly, and the C flag unconditionally. >> cmp r0, #0 >> @@ -865,57 +916,82 @@ ARM_FUNC_ALIAS aeabi_cfcmple aeabi_cfcmpeq >> cmnmi r0, #0 >> RETLDM "r0, r1, r2, r3" >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_cfcmple >> FUNC_END aeabi_cfcmpeq >> FUNC_END aeabi_cfrcmple >> >> ARM_FUNC_START aeabi_fcmpeq >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cfcmple >> do_it eq, e >> moveq r0, #1 @ Equal to. >> movne r0, #0 @ Less than, greater than, or unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fcmpeq >> >> ARM_FUNC_START aeabi_fcmplt >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cfcmple >> do_it cc, e >> movcc r0, #1 @ Less than. >> movcs r0, #0 @ Equal to, greater than, or unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fcmplt >> >> ARM_FUNC_START aeabi_fcmple >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cfcmple >> do_it ls, e >> movls r0, #1 @ Less than or equal to. >> movhi r0, #0 @ Greater than or unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fcmple >> >> ARM_FUNC_START aeabi_fcmpge >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cfrcmple >> do_it ls, e >> movls r0, #1 @ Operand 2 is less than or equal to operand 1. >> movhi r0, #0 @ Operand 2 greater than operand 1, or unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fcmpge >> >> ARM_FUNC_START aeabi_fcmpgt >> + CFI_START_FUNCTION >> + >> + str lr, [sp, #-8]! @ sp -= 8 >> + .cfi_adjust_cfa_offset 8 @ CFA is now sp + previousOffset + 8 >> + .cfi_rel_offset lr, 0 @ lr is at sp >> >> - str lr, [sp, #-8]! >> ARM_CALL aeabi_cfrcmple >> do_it cc, e >> movcc r0, #1 @ Operand 2 is less than operand 1. >> @@ -923,6 +999,7 @@ ARM_FUNC_START aeabi_fcmpgt >> @ or they are unordered. >> RETLDM >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fcmpgt >> >> #endif /* L_cmpsf2 */ >> @@ -931,6 +1008,7 @@ ARM_FUNC_START aeabi_fcmpgt >> >> ARM_FUNC_START unordsf2 >> ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 >> + CFI_START_FUNCTION >> >> mov r2, r0, lsl #1 >> mov r3, r1, lsl #1 >> @@ -947,6 +1025,7 @@ ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 >> 3: mov r0, #1 @ arguments are unordered. >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_fcmpun >> FUNC_END unordsf2 >> >> @@ -956,6 +1035,7 @@ ARM_FUNC_ALIAS aeabi_fcmpun unordsf2 >> >> ARM_FUNC_START fixsfsi >> ARM_FUNC_ALIAS aeabi_f2iz fixsfsi >> + CFI_START_FUNCTION >> >> @ check exponent range. >> mov r2, r0, lsl #1 >> @@ -989,6 +1069,7 @@ ARM_FUNC_ALIAS aeabi_f2iz fixsfsi >> 4: mov r0, #0 @ What should we convert NAN to? >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_f2iz >> FUNC_END fixsfsi >> >> @@ -998,6 +1079,7 @@ ARM_FUNC_ALIAS aeabi_f2iz fixsfsi >> >> ARM_FUNC_START fixunssfsi >> ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi >> + CFI_START_FUNCTION >> >> @ check exponent range. >> movs r2, r0, lsl #1 >> @@ -1027,6 +1109,7 @@ ARM_FUNC_ALIAS aeabi_f2uiz fixunssfsi >> 4: mov r0, #0 @ What should we convert NAN to? >> RET >> >> + CFI_END_FUNCTION >> FUNC_END aeabi_f2uiz >> FUNC_END fixunssfsi >> >> diff --git a/libgcc/config/arm/lib1funcs.S b/libgcc/config/arm/lib1funcs.S >> index d2d0d20..4b63924 100644 >> --- a/libgcc/config/arm/lib1funcs.S >> +++ b/libgcc/config/arm/lib1funcs.S >> @@ -1965,6 +1965,16 @@ LSYM(Lchange_\register): >> >> #endif /* Arch supports thumb. */ >> >> +.macro CFI_START_FUNCTION >> + .cfi_startproc >> + .cfi_remember_state >> +.endm >> + >> +.macro CFI_END_FUNCTION >> + .cfi_restore_state >> + .cfi_endproc >> +.endm >> + >> #ifndef __symbian__ >> #ifndef __ARM_ARCH_6M__ >> #include "ieee754-df.S" -- Martin Galvan Software Engineer Taller Technologies Argentina San Lorenzo 47, 3rd Floor, Office 5 Córdoba, Argentina Phone: 54 351 4217888 / +54 351 4218211 ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM 2015-04-28 17:10 ` Martin Galvan @ 2015-05-04 20:51 ` Martin Galvan 2015-05-10 22:16 ` Fwd: " Martin Galvan 0 siblings, 1 reply; 6+ messages in thread From: Martin Galvan @ 2015-05-04 20:51 UTC (permalink / raw) To: ramrad01; +Cc: gcc-patches Hi Ramana! Sorry to bother, but I looked at the repository and didn't see this committed. As I don't have write access could you please commit this for me? Thanks a lot! On Tue, Apr 28, 2015 at 2:07 PM, Martin Galvan <martin.galvan@tallertechnologies.com> wrote: > Thanks a lot. I don't have write access to the repository, could you > commit this for me? > > On Tue, Apr 28, 2015 at 1:21 PM, Ramana Radhakrishnan > <ramana.gcc@googlemail.com> wrote: >> On Tue, Apr 28, 2015 at 4:19 PM, Martin Galvan >> <martin.galvan@tallertechnologies.com> wrote: >>> This patch adds CFI directives to the soft floating point support code for ARM. >>> >>> Previously, if we tried to do a backtrace from that code in a debug session we'd >>> get something like this: >>> >>> (gdb) bt >>> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1082 >>> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1158 >>> #2 0xf5c28f5c in ?? () >>> Backtrace stopped: previous frame identical to this frame (corrupt stack?) >>> >>> Now we'll get something like this: >>> >>> (gdb) bt >>> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1156 >>> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1263 >>> #2 0x00000dc8 in __aeabi_dcmpeq () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1285 >>> #3 0x00000504 in main () >>> >>> I have a company-wide copyright assignment. I don't have commit access, though, so it would be great if anyone could commit this for me. >>> >>> Thanks a lot! >>> >> >> this is OK , thanks. Sorry about the delay in reviewing this. >> >> Ramana ^ permalink raw reply [flat|nested] 6+ messages in thread
* Fwd: [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM 2015-05-04 20:51 ` Martin Galvan @ 2015-05-10 22:16 ` Martin Galvan 2015-05-11 7:45 ` Ramana Radhakrishnan 0 siblings, 1 reply; 6+ messages in thread From: Martin Galvan @ 2015-05-10 22:16 UTC (permalink / raw) To: ramrad01, gcc-patches Hi Ramana! Sorry to bother, but I looked at the repository and didn't see this committed. As I don't have write access could you please commit this for me? Thanks a lot! On Tue, Apr 28, 2015 at 2:07 PM, Martin Galvan <martin.galvan@tallertechnologies.com> wrote: > Thanks a lot. I don't have write access to the repository, could you > commit this for me? > > On Tue, Apr 28, 2015 at 1:21 PM, Ramana Radhakrishnan > <ramana.gcc@googlemail.com> wrote: >> On Tue, Apr 28, 2015 at 4:19 PM, Martin Galvan >> <martin.galvan@tallertechnologies.com> wrote: >>> This patch adds CFI directives to the soft floating point support code for ARM. >>> >>> Previously, if we tried to do a backtrace from that code in a debug session we'd >>> get something like this: >>> >>> (gdb) bt >>> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1082 >>> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1158 >>> #2 0xf5c28f5c in ?? () >>> Backtrace stopped: previous frame identical to this frame (corrupt stack?) >>> >>> Now we'll get something like this: >>> >>> (gdb) bt >>> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1156 >>> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1263 >>> #2 0x00000dc8 in __aeabi_dcmpeq () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1285 >>> #3 0x00000504 in main () >>> >>> I have a company-wide copyright assignment. I don't have commit access, though, so it would be great if anyone could commit this for me. >>> >>> Thanks a lot! >>> >> >> this is OK , thanks. Sorry about the delay in reviewing this. >> >> Ramana -- Martin Galvan Software Engineer Taller Technologies Argentina San Lorenzo 47, 3rd Floor, Office 5 Córdoba, Argentina Phone: 54 351 4217888 / +54 351 4218211 ^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: Fwd: [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM 2015-05-10 22:16 ` Fwd: " Martin Galvan @ 2015-05-11 7:45 ` Ramana Radhakrishnan 0 siblings, 0 replies; 6+ messages in thread From: Ramana Radhakrishnan @ 2015-05-11 7:45 UTC (permalink / raw) To: Martin Galvan, gcc-patches On 10/05/15 23:16, Martin Galvan wrote: > Hi Ramana! Sorry to bother, but I looked at the repository and didn't > see this committed. As I don't have write access could you please > commit this for me? > > Thanks a lot! > sorry about the slow response, I was travelling for a bit and missed your emails. Trying your patch out gives me failures possibly because my mail client munged it when it received this inline. Can you please rebase if necessary, test and send it again as an attachment ? patch -p1 --dry-run < ~/Downloads/martin-patch.txt checking file libgcc/config/arm/ieee754-df.S Hunk #2 FAILED at 57. Hunk #3 succeeded at 70 with fuzz 2. Hunk #4 FAILED at 86. Hunk #5 FAILED at 153. Hunk #6 FAILED at 418. Hunk #7 FAILED at 425. Hunk #8 FAILED at 440. Hunk #9 FAILED at 462. Hunk #10 FAILED at 485. Hunk #11 FAILED at 555. Hunk #12 FAILED at 566. Hunk #13 FAILED at 601. Hunk #14 FAILED at 653. Hunk #15 FAILED at 720. Hunk #16 FAILED at 868. Hunk #17 FAILED at 1057. Hunk #18 FAILED at 1068. Hunk #19 FAILED at 1082. Hunk #20 FAILED at 1090. Hunk #21 FAILED at 1122. Hunk #22 FAILED at 1133. Hunk #23 succeeded at 1145 with fuzz 2. Hunk #24 FAILED at 1155. Hunk #25 FAILED at 1168. Hunk #26 FAILED at 1228. Hunk #27 succeeded at 1236 with fuzz 2. Hunk #28 FAILED at 1254. Hunk #29 succeeded at 1263 with fuzz 2. Hunk #30 FAILED at 1297. Hunk #31 succeeded at 1306 with fuzz 2. Hunk #32 FAILED at 1336. Hunk #33 succeeded at 1345 with fuzz 2. Hunk #34 FAILED at 1410. 27 out of 34 hunks FAILED checking file libgcc/config/arm/ieee754-sf.S Hunk #1 FAILED at 31. Hunk #4 FAILED at 294. Hunk #9 FAILED at 460. Hunk #10 FAILED at 471. Hunk #16 FAILED at 845. Hunk #20 FAILED at 898. 6 out of 27 hunks FAILED checking file libgcc/config/arm/lib1funcs.S regards Ramana > On Tue, Apr 28, 2015 at 2:07 PM, Martin Galvan > <martin.galvan@tallertechnologies.com> wrote: >> Thanks a lot. I don't have write access to the repository, could you >> commit this for me? >> >> On Tue, Apr 28, 2015 at 1:21 PM, Ramana Radhakrishnan >> <ramana.gcc@googlemail.com> wrote: >>> On Tue, Apr 28, 2015 at 4:19 PM, Martin Galvan >>> <martin.galvan@tallertechnologies.com> wrote: >>>> This patch adds CFI directives to the soft floating point support code for ARM. >>>> >>>> Previously, if we tried to do a backtrace from that code in a debug session we'd >>>> get something like this: >>>> >>>> (gdb) bt >>>> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1082 >>>> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1158 >>>> #2 0xf5c28f5c in ?? () >>>> Backtrace stopped: previous frame identical to this frame (corrupt stack?) >>>> >>>> Now we'll get something like this: >>>> >>>> (gdb) bt >>>> #0 __nedf2 () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1156 >>>> #1 0x00000db6 in __aeabi_cdcmple () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1263 >>>> #2 0x00000dc8 in __aeabi_dcmpeq () at ../../../../../../gcc-4.9.2/libgcc/config/arm/ieee754-df.S:1285 >>>> #3 0x00000504 in main () >>>> >>>> I have a company-wide copyright assignment. I don't have commit access, though, so it would be great if anyone could commit this for me. >>>> >>>> Thanks a lot! >>>> >>> >>> this is OK , thanks. Sorry about the delay in reviewing this. >>> >>> Ramana > > ^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2015-05-11 7:45 UTC | newest] Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2015-04-28 15:51 [PING 2][PATCH] libgcc: Add CFI directives to the soft floating point support code for ARM Martin Galvan 2015-04-28 16:22 ` Ramana Radhakrishnan 2015-04-28 17:10 ` Martin Galvan 2015-05-04 20:51 ` Martin Galvan 2015-05-10 22:16 ` Fwd: " Martin Galvan 2015-05-11 7:45 ` Ramana Radhakrishnan
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