鍘熸枃鍦板潃锛歅ropermemoryalignmentinGotypePart1struct{aboolbint32cint8dint64ebyte}鍦ㄥ紑濮嬩箣鍓嶏紝甯屾湜澶у璁＄畻涓€涓婸art1鐨勬€诲ぇ灏忔槸澶氬皯锛焒uncmain(){fmt.Printf("boolsize:%d\n",unsafe.Sizeof(bool(true)))fmt.Printf("int32size:%d\n",unsafe.Sizeof(int32(0)))fmt.Printf("int8澶у皬:%d\n",unsafe.Sizeof(int8(0)))fmt.Printf("int64澶у皬:%d\n",unsafe.Sizeof(int64(0)))fmt.Printf("瀛楄妭澶у皬锛?d\n",unsafe.Sizeof(byte(0)))fmt.Printf("瀛楃涓插ぇ灏忥細%d\n",unsafe.Sizeof("EDDYCJY"))}杈撳嚭缁撴灉锛歜oolsize:1int32size:4int8size:1int64size:8bytesize:1stringsize:16杩欐牱绠楀嚭鏉art1缁撴瀯浣撶殑鍐呭瓨澶у皬涓?+4+1+8+1=15瀛楄妭銆傜浉淇℃湁灏忎紮浼存槸杩欐牱璁＄畻杩囩殑锛屽ソ鍍忎篃娌′粈涔堥棶棰樸€傜湡瀹炴儏鍐靛浣曪紵璁╂垜浠疄闄呰皟鐢ㄥ畠锛屽涓嬫墍绀猴細n",unsafe.Sizeof(part1),unsafe.Alignof(part1))}杈撳嚭缁撴灉锛歱art1size:32,align:8鏈€缁堣緭鍑哄崰鐢?2瀛楄妭銆傝繖涓庨鏈熺殑缁撴灉瀹屽叏涓嶅悓銆傝繖鍏呭垎璇存槑浠ュ墠鐨勮绠楁柟娉曟槸閿欒鐨勩€備负浠€涔堬紵杩欓噷蹇呴』瑕佹彁鍒扳€滃唴瀛樺榻愨€濈殑姒傚康锛岃繖鏍锋垜浠墠鑳界敤姝ｇ‘鐨勫Э鍔挎潵璁＄畻銆傛帴涓嬫潵锛屾垜浠皢璇︾粏璇磋浠€涔堟槸鍐呭瓨瀵归綈銆傛湁鐨勬湅鍙嬪彲鑳借涓鸿蹇嗛槄璇绘槸涓€涓畝鍗曠殑璇嶃€傛鏁扮粍鏀剧疆涓婂浘涓轰竴鍧戜竴钀濆崪鐨勫唴瀛樿鍙栨柟寮忋€備絾瀹為檯涓奀PU骞朵笉鏄竴涓瓧鑺備竴涓瓧鑺傚湴璇诲啓鍐呭瓨銆傚弽涔嬶紝CPU鏄竴涓竴涓湴璇诲彇鍐呭瓨锛屽潡澶у皬鍙互鏄?銆?銆?銆?銆?6瀛楄妭绛夛紝鍧楀ぇ灏忔垜浠О涔嬩负鍐呭瓨璁块棶绮掑害銆傚涓嬪浘鎵€绀猴細绀轰緥涓亣璁捐闂矑搴︿负4锛孋PU浠?瀛楄妭鐨勮闂矑搴﹁鍐欏唴瀛樸€傝繖鏄纭殑濮垮娍涓轰粈涔堣鍏冲績瀵归綈鎮ㄦ鍦ㄧ紪鍐欑殑浠ｇ爜鍦ㄦ€ц兘锛圕PU锛屽唴瀛橈級鏂归潰鏈変竴瀹氱殑瑕佹眰鎮ㄦ鍦ㄥ鐞嗗悜閲忔柟闈㈢殑鎸囦护鏌愪簺纭欢骞冲彴锛圓RM锛夋灦鏋勪笉鏀寔鏈榻愮殑鍐呭瓨璁块棶AlsoAs浣滀负涓€涓伐绋嬪笀锛屽涔犺繖涓煡璇嗙偣涔熸槸寰堟湁蹇呰鐨?)涓轰粈涔堣瀵归綈骞冲彴锛堝彲绉绘鎬э級锛氫笉鏄墍鏈夌殑纭欢骞冲彴閮藉彲浠ヨ闂换鎰忓湴鍧€鐨勪换鎰忔暟鎹€備緥濡傦細鐗瑰畾鐨勭‖浠跺钩鍙板彧鍏佽璁块棶鐗瑰畾鍦板潃鐨勭壒瀹氱被鍨嬬殑鏁版嵁锛屽惁鍒欎細瀵艰嚧寮傚父鎯呭喌銆傚鐞嗗榻愬拰鎿嶄綔銆傝€岃嚜瀵归綈瀛樺偍鍣ㄥ彧闇€瑕佷竴娆¤闂氨鍙互瀹屾垚璇诲彇鍔ㄤ綔銆備笂鍥句腑锛屽鏋滀粠Index1寮€濮嬭鍙栵紝浼氬嚭鐜板緢宕╂簝鐨勯棶棰樸€傚洜涓哄畠鐨勫唴瀛樿闂竟鐣屾病鏈夊榻愩€傛墍浠PU鍋氫簡涓€浜涢澶栫殑澶勭悊銆傚涓嬶細CPU绗竴娆¤鍙栨湭瀵归綈鍦板潃澶勭殑绗竴涓唴瀛樺潡锛岃鍙栫殑鏄?-3瀛楄妭銆傚苟鍒犻櫎涓嶉渶瑕佺殑瀛楄妭0CPU鍐嶆璇诲彇鏈榻愬湴鍧€澶勭殑绗簩涓唴瀛樺潡锛岃鍙?-7涓瓧鑺傘€傚苟鍘绘帀涓嶉渶瑕佺殑5銆?銆?瀛楄妭锛屽皢1-4瀛楄妭鐨勬暟鎹悎骞跺埌瀵勫瓨鍣ㄤ腑銆備粠涓婇潰鐨勮繃绋嬪彲浠ョ湅鍑猴紝涓嶅仛鈥滃唴瀛樺榻愨€濇湁鐐光€滈夯鐑︹€濄€傚洜涓轰細澧炲姞寰堝鑰楁椂鐨勫姩浣滐紝杩欓噷鍋囪鍋氬唴瀛樺榻愶紝浠嶪ndex0璇诲彇4涓瓧鑺傦紝鍙渶瑕佽鍙栦竴娆★紝涓嶉渶瑕侀澶栫殑鎿嶄綔銆傝繖鏄剧劧鏁堢巼鏇撮珮锛岃€屼笖鏄爣鍑嗙殑绌洪棿鎹㈡椂闂存柟寮忋€傞粯璁ょ郴鏁颁笉鍚屻€備笉鍚屽钩鍙扮殑缂栬瘧鍣ㄩ兘鏈夎嚜宸遍粯璁ょ殑鈥滃榻愮郴鏁扳€濓紝鍙互閫氳繃棰勭紪璇戝懡浠?pragmapack(n)鏉ユ敼鍙橈紝鍏朵腑n鏄寚鈥滃榻愮郴鏁扳€濄€備竴鑸潵璇达紝鎴戜滑甯哥敤骞冲彴鐨勭郴鏁板涓嬶細32浣嶏細464浣嶏細8鍙﹀闇€瑕佹敞鎰忕殑鏄紝涓嶅悓鐨勭‖浠跺钩鍙板崰鐢ㄧ殑澶у皬鍜屽榻愬€煎彲鑳戒笉鍚屻€傚洜姝わ紝鏈枃鐨勪环鍊煎苟涓嶆槸鍞竴鐨勩€傝皟璇曟椂锛屽繀椤绘牴鎹満鍣ㄧ殑瀹為檯鎯呭喌鑰冭檻鏋勪欢瀵逛腑銆俧uncmain(){fmt.Printf("boolalign:%d\n",unsafe.Alignof(bool(true)))fmt.Printf("int32align:%d\n",unsafe.Alignof(int32(0)))fmt.Printf("int8瀵归綈:%d\n",unsafe.Alignof(int8(0)))fmt.Printf("int64瀵归綈:%d\n",unsafe.Alignof(int64(0)))fmt.Printf("瀛楄妭瀵归綈:%d\n",unsafe.Alignof(byte(0)))fmt.Printf("stringalign:%d\n",unsafe.Alignof("EDDYCJY"))fmt.Printf("mapalign:%d\n",unsafe.Alignof(map[string]string{}))}杈撳嚭缁撴灉锛歜oolalign:1int32align:4int8align:1int64align:8bytealign:1stringalign:8mapalign:8Go涓彲浠ヨ皟鐢╱nsafe.Alignof杩斿洖瀵瑰簲绫诲瀷鐨勫榻愮郴鏁般€傞€氳繃瑙傚療杈撳嚭缁撴灉锛屾垜浠彲浠ョ煡閬撳熀鏈兘鏄?^n锛屾渶澶у€间笉浼氳秴杩?銆傝繖鏄洜涓烘垜鐨勫彲绉绘锛?4浣嶏級缂栬瘧鍣ㄩ粯璁ゅ榻愬洜瀛愭槸8锛屾墍浠ユ渶澶у€间笉浼氳秴杩囪繖涓暟瀛椼€傛暣浣撳榻愬湪涓婁竴鑺備腑鎻愬埌浜嗙粨鏋勪綋涓殑鎴愬憳鍙橀噺瑕佸瓧鑺傚榻愩€傞偅涔堢悊鎵€褰撶劧鐨勮涓轰綔涓烘渶缁堢粨鏋滅殑缁撴瀯浣撲篃鏄渶瑕佸瓧鑺傚榻愮殑瀵归綈瑙勫垯缁撴瀯浣撶殑鎴愬憳鍙橀噺锛岀涓€涓垚鍛樺彉閲忕殑鍋忕Щ閲忎负0銆俧uture蹇呴』鏄紪璇戝櫒榛樿鐨勫榻愰暱搴︼紙#pragmapack(n)锛夋垨鑰呭綋鍓嶆垚鍛樺彉閲忕被鍨嬬殑闀垮害锛坲nsafe.Sizeof锛夛紝鍙栨渶灏忓€间綔涓哄綋鍓嶇被鍨嬬殑瀵归綈鍊笺€傚畠鐨勫亸绉婚噺蹇呴』鏄粨鏋勪綋鑷韩瀵归綈鍊肩殑鏁存暟鍊嶏紝骞朵笖瀵归綈鍊煎繀椤绘槸缂栬瘧鍣ㄩ粯璁ょ殑瀵归綈闀垮害锛?pragmapack(n)锛夋垨缁撴瀯浣撴墍鏈夋垚鍛樺彉閲忕被鍨嬩腑鐨勬渶澶ч暱搴︼紝鍙栧叾鏈€灏忔暣鏁板€嶆暟浣滀负瀵归綈鍊肩粨鍚堜互涓婁袱鐐瑰彲鐭ワ紝濡傛灉缂栬瘧鍣ㄩ粯璁ょ殑瀵归綈闀垮害锛?pragmapack(n)锛夎秴杩囦簡缁撴瀯浣撲腑鎴愬憳鍙橀噺绫诲瀷鐨勬渶澶ч暱搴︼紝鍒欓粯璁ゅ榻愰暱搴︽病鏈夋剰涔夈€傚垎鏋愯繃绋嬫帴涓嬫潵鎴戜滑涓€璧锋潵鍒嗘瀽涓€涓嬶紝鈥滃畠鈥濆埌搴曠粡鍘嗕簡浠€涔堬紝褰卞搷浜嗏€滈鏈熲€濈殑缁撴灉鎴愬憳鍙橀噺绫诲瀷鍋忕Щ鏈韩鍗犵敤abool01瀛楄妭瀵归綈娌℃湁13bint3244cint881瀛楄妭瀵归綈娌℃湁97dint64168ebyte241瀛楄妭瀵归綈娌℃湁257鎬诲崰鐢ㄥぇ灏?-32鎴愬憳瀵归綈绗竴涓垚鍛榓绫诲瀷涓篵oolsize/alignment鍊间负1瀛楄妭鍒濆鍦板潃锛宱ffset涓?銆傚崰鎹涓€涓綅缃紝绗簩涓垚鍛榖涓篿nt32绫诲瀷锛屽叾size/alignment鍊间负4瀛楄妭銆傛牴鎹鍒?锛屽畠鐨刼ffset蹇呴』鏄?鐨勬暣鏁板€嶃€俹ffset纭畾涓?锛屾墍浠its2-4鏄疨adding銆傚苟涓斾粠绗?鍒扮8浣嶅～鍏呭綋鍓嶅€笺€傚涓嬶細axxx|bbbb绗笁涓垚鍛榗绫诲瀷鏄痠nt8澶у皬/瀵归綈鍊兼槸1瀛楄妭鏍规嵁瑙勫垯1锛屽畠鐨勫亸绉婚噺蹇呴』鏄?鐨勬暣鏁板€嶃€傚綋鍓嶅亸绉婚噺鏄?銆備笉闇€瑕侀澶栧榻愶紝濉厖1瀛楄妭鍒扮9浣嶃€傚涓嬶細axxx|bbbb|c...绗洓涓垚鍛榙绫诲瀷涓篿nt64size/alignment鍊间负8瀛楄妭鏍规嵁瑙勫垯1锛屽叾鍋忕Щ閲忓繀椤绘槸8鐨勬暣鏁板€嶃€傚亸绉婚噺纭畾涓?6锛屾墍浠its9-16鏄～鍏呫€傚綋鍓嶅€间粠绗?7浣嶅啓鍏ュ埌绗?4浣嶃€傚涓嬶細axxx|bbbb|cxxx|xxxx|dddd|dddd绗簲涓垚鍛榚绫诲瀷涓篵ytesize/alignment鍊间负1byte鏍规嵁瑙勫垯1锛屽叾鍋忕Щ閲忓繀椤绘槸1鐨勬暣鏁板€嶏紝褰撳墠鍋忕Щ閲忎负24鍚﹂渶瑕侀澶栧榻愶紝pad1bytetoposition25.濡備笅锛歛xxx|bbbb|cxxx|xxxx|dddd|dddd|e...鏁翠綋瀵归綈姣忎釜鎴愬憳鍙橀噺瀵归綈鍚庯紝鏍规嵁瑙勫垯2锛屾暣涓粨鏋勪綋鏈韩搴旇杩樿鎸夊瓧鑺傚榻愶紝鍥犱负鍙互鍙戠幇鍙兘涓嶆槸2^n锛岀敋鑷充笉鏄€嶆暟銆傝鍒?鏄剧劧涓嶇鍚堝榻愯鍒欙紝寰楀埌鐨勫榻愬€间负8銆傛鏃跺亸绉婚噺涓?5锛屼笉鏄?鐨勫€嶆暟銆傚洜姝ょ‘瀹氬亸绉婚噺涓?2銆傜粨鏋勪綋鐨勫榻愮粨鏋淧art1鍐呭瓨甯冨眬锛歛xxx|bbbb|cxxx|xxxx|dddd|dddd|exxx|xxxx灏忕粨閫氳繃鏈妭鐨勫垎鏋愶紝鎴戜滑鍙互鐭ラ亾涓轰粈涔堝墠闈㈢殑鈥滆绠椻€濇槸閿欒鐨勶紵鏄洜涓哄疄闄呯殑鍐呭瓨绠＄悊骞朵笉鏄€滀竴涓悵鍗滀竴涓潙鈥濈殑鎬濊矾銆傝€屾槸涓€鍧椾竴鍧楃殑銆傝繖娈佃鍐欐槸閫氳繃绌洪棿鎹㈡椂闂达紙鏁堢巼锛夌殑鎬濊矾鏉ュ畬鎴愮殑銆傚彟澶栵紝杩樿鍏奸【涓嶅悓骞冲彴鐨勫唴瀛樻搷浣溿€傚湪涓婁竴鑺傛垜浠彲浠ョ煡閬擄紝鏍规嵁鎴愬憳鍙橀噺鐨勭被鍨嬶紝缁撴瀯浣撶殑鍐呭瓨浼氭湁瀵归綈绛夊姩浣溿€傚鏋滃瓧娈电殑椤哄簭涓嶅悓锛屾槸鍚︿細鏈変换浣曞彉鍖栵紵璁╂垜浠竴璧疯瘯璇?-)typePart1struct{aboolbint32cint8dint64ebyte}typePart2struct{ebytecint8aboolbint32dint64}funcmain(){part1:=Part1{}part2:=Part2{}fmt.Printf("part1size:%d,align:%d\n",unsafe.Sizeof(part1),unsafe.Alignof(part1))fmt.Printf("part2size:%d,align:%d\n",unsafe.Sizeof(part2),unsafe.Alignof(part2))}杈撳嚭缁撴灉锛歱art1size:32,align:8part2size:16,align:8浣犲彲浠ュ缁撴灉鎰熷埌鎯婂枩锛屽彧鏄?Simple鈥濇敼鍙樻垚鍛樺彉閲忓瓧娈电殑椤哄簭浼氭敼鍙樼粨鏋勭殑澶у皬銆備笅闈㈡垜浠竴璧锋潵鍒嗘瀽涓€涓婸art2锛岀湅鐪嬪畠鐨勫唴閮ㄧ粨鏋勫拰涔嬪墠鐨勬湁浠€涔堜笉鍚岋紝瀵艰嚧浜嗚繖鏍风殑缁撴灉锛熷垎鏋愯繃绋嬫垚鍛樺彉閲忕被鍨媜ffset鏈韩鍗犵敤ebyte01cint811abool21bytealignmentno31bint3244dint6488totaloccupiedsize--16memberalignment绗竴涓垚鍛榚绫诲瀷涓篵ytesize/alignmentvalue涓?瀛楄妭璧峰鍦板潃锛宱ffset涓?銆傚崰鎹1涓綅缃紝绗簩涓垚鍛榗绫诲瀷涓篿nt8锛屽ぇ灏?瀵归綈鍊间负1瀛楄妭锛屾牴鎹鍒?锛屽叾鍋忕Щ閲忓繀椤讳负1鐨勬暣鏁板€嶏紝褰撳墠鍋忕Щ閲忎负2銆備笉闇€瑕侀澶栧榻愩€傜涓変釜鎴愬憳a鏄?瀛楄妭鐨刡ool澶у皬/瀵归綈鍊笺€傛牴鎹鍒?锛屽畠鐨刼ffset蹇呴』鏄?鐨勬暣鏁板€嶏紝褰撳墠offset鏄?锛屼笉闇€瑕侀澶栧榻愩€傜鍥涗釜鎴愬憳b绫诲瀷鏄痠nt32锛屽畠鐨勫ぇ灏?瀵归綈鍊兼槸4涓瓧鑺傘€傛牴鎹鍒?锛屽畠鐨勫亸绉婚噺蹇呴』鏄?鐨勬暣鏁板€嶃€傚亸绉婚噺纭畾涓?锛屾墍浠ョ3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