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authoriximeow <me@iximeow.net>2019-02-18 18:06:24 -0800
committeriximeow <me@iximeow.net>2020-01-12 17:28:07 -0800
commitf62de4c3eff32c4f3709d5d690671771fd453701 (patch)
tree2e78ffb027068ccd80fcb0de8f28d6790016e577
parent4f0cb26cacd5bf7c42850407bfab29bdba5986e4 (diff)
add some notes in README
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+## ARM arch notes:
+
+### Register Names
+Reproduced from [infocenter.arm.com](http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0473c/CJAJBFHC.html):
+| Name | Maps To | Meaning |
+| ---- | ------- | ------- |
+| r0-r15 | r0-r15 | These are the the registers! |
+| a1-a4 | r0-r3 | Argument, result, or scratch registers |
+| v1-v8 | r4-r11 | Variable registers |
+| sb | r9 | Static base register |
+| fp | r11 | Frame pointer\* |
+| ip | r12 | Intra-procedure call register |
+| sp | r13 | Stack pointer |
+| lr | r14 | link register |
+| pc | r15 | program counter |
+
+\* `fp` does not appear to be explicitly referenced in ARM documentation, and mapping to r11 looks to be OS (Windows/Linux?) convention.