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Cleaned up lists and spacing on llvm_concepts.rst

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Maggie Mari 2012-08-12 15:51:47 -05:00
commit 1cbcd2f913
1 changed files with 19 additions and 17 deletions
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docs/source/doc/llvm_concepts.rst
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@ -27,9 +27,11 @@ follow these steps:
- create a function of type *tf* named *sum* - create a function of type *tf* named *sum*
- add a *basic block* to the function - add a *basic block* to the function
- using a helper object called an *instruction builder*, add two - using a helper object called an *instruction builder*, add two
instructions into the basic block: . an instruction to add the two instructions into the basic block:
arguments and store the result into a temporary variable . a return - an instruction to add the two
instruction to return the value of the temporary variable arguments and store the result into a temporary variable
- a return
instruction to return the value of the temporary variable
(A basic block is a block of instructions.) (A basic block is a block of instructions.)
@ -116,32 +118,32 @@ The corresponding LLVM assembly:
.. code-block:: llvm .. code-block:: llvm
; ModuleID = '/tmp/webcompile/_7149_0.bc' ; ModuleID = '/tmp/webcompile/_7149_0.bc'
target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64" target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64"
target triple = "x86_64-linux-gnu" target triple = "x86_64-linux-gnu"
define i32 @sum(i32 %n) nounwind readnone { define i32 @sum(i32 %n) nounwind readnone {
entry: entry:
%0 = icmp eq i32 %n, 0 ; [#uses=1] %0 = icmp eq i32 %n, 0 ; [#uses=1]
br i1 %0, label %bb2, label %bb1 br i1 %0, label %bb2, label %bb1
bb1: ; preds = %entry bb1: ; preds = %entry
%1 = add i32 %n, -1 ; [#uses=2] %1 = add i32 %n, -1 ; [#uses=2]
%2 = icmp eq i32 %1, 0 ; [#uses=1] %2 = icmp eq i32 %1, 0 ; [#uses=1]
br i1 %2, label %sum.exit, label %bb1.i br i1 %2, label %sum.exit, label %bb1.i
bb1.i: ; preds = %bb1 bb1.i: ; preds = %bb1
%3 = add i32 %n, -2 ; [#uses=1] %3 = add i32 %n, -2 ; [#uses=1]
%4 = tail call i32 @sum(i32 %3) nounwind ; [#uses=1] %4 = tail call i32 @sum(i32 %3) nounwind ; [#uses=1]
%5 = add i32 %4, %1 ; [#uses=1] %5 = add i32 %4, %1 ; [#uses=1]
br label %sum.exit br label %sum.exit
sum.exit: ; preds = %bb1.i, %bb1 sum.exit: ; preds = %bb1.i, %bb1
%6 = phi i32 [ %5, %bb1.i ], [ 0, %bb1 ] ; [#uses=1] %6 = phi i32 [ %5, %bb1.i ], [ 0, %bb1 ] ; [#uses=1]
%7 = add i32 %6, %n ; [#uses=1] %7 = add i32 %6, %n ; [#uses=1]
ret i32 %7 ret i32 %7
bb2: ; preds = %entry bb2: ; preds = %entry
ret i32 0 ret i32 0
} }
Note the usage of SSA form. The long string called ``target datalayout`` Note the usage of SSA form. The long string called ``target datalayout``